DNA: In Search of…Full and Half-Siblings

This is the fifth article in our series of articles about searching for unknown close family members, specifically; parents, grandparents, or siblings. However, these same techniques can be applied by genealogists to identify ancestors further back in time as well.

Please note that if a family member has tested and you do NOT see their results, ask them to verify that they have chosen to allow matching and for other people to view them in their match list. That process varies at different vendors.

You can also ask if they can see you in their results.

All Parties Need to Test

Searching for unknown siblings isn’t exactly searching, because to find them, they, themselves, or their descendant(s) must have taken a DNA test at the same vendor where you tested or uploaded a DNA file.

You may know through any variety of methods that they exist, or might exist, but if they don’t take a DNA test, you can’t find them using DNA. This might sound obvious, but I see people commenting and not realizing that the other sibling(s) must test too – and they may not have.

My first questions when someone comments in this vein are:

  1. Whether or not they are positive their sibling actually tested, meaning actually sent the test in to the vendor, and it was received by the testing company. You’d be surprised how many tests are living in permanent residence on someone’s countertop until it gets pushed into the drawer and forgotten about.
  2. If the person has confirmed that their sibling has results posted. They may have returned their test, but the results aren’t ready yet or there was a problem.
  3. AND that both people have authorized matching and sharing of results. Don’t hesitate to reach out to your vendor’s customer care if you need help with this.

Sibling Scenarios

The most common sibling scenarios are when one of two things happens:

  • A known sibling tests, only to discover that they don’t match you in the full sibling range, or not at all, when you expected they would
  • You discover a surprise match in the full or half-sibling range

Let’s talk about these scenarios and how to determine:

  • If someone is a sibling
  • If they are a full or half-sibling
  • If a half-sibling, if they descend from your mother or father

As with everything else genetic, we’ll be gathering and analyzing different pieces of evidence along the way.

Full and Half-Siblings

Just to make sure we are all on the same page:

  • A full sibling is someone who shares both parents with you.
  • A half-sibling is someone who shares one parent with you, but not the other parent.
  • A step-sibling is someone who shares no biological parents with you. This situation occurs when your parent marries their parent, after you are both born, and their parent becomes your step-parent. You share neither of your biological parents with a step-sibling, so you share no DNA and will not show up on each other’s match lists.
  • A three-quarters sibling is someone with whom you share one parent, but two siblings are the other parent. For example, you share the same mother, but one brother fathered you, and your father’s brother fathered your sibling. Yes, this can get very messy and is almost impossible for a non-professional to sort through, if even then. (This is not a solicitation. I do not take private clients.) We will not be addressing this situation specifically.

Caution

With any search for unknown relatives, you have no way of knowing what you will find.

In one’s mind, there are happy reunions, but you may experience something entirely different. Humans are human. Their stories are not always happy or rosy. They may have made mistakes they regret. Or they may have no regrets about anything.

Your sibling may not know about you or the situation under which you, or they, were born. Some women were victims of assault and violence, which is both humiliating and embarrassing. I wrote about difficult situations, here.

Your sibling or close family member may not be receptive to either you, your message, or even your existence. Just be prepared, because the seeking journey may not be pain-free for you or others, and may not culminate with or include happy reunions.

On the other hand, it may.

Please step back and ponder a bit about the journey you are about to undertake and the possible people that may be affected, and how. This box, once opened, cannot be closed again. Be sure you are prepared.

On the other hand, sometimes that box lid pops off, and the information simply falls in your lap one day when you open your match list, and you find yourself sitting there, in shock, staring at a match, trying to figure out what it all means.

Congratulations, You Have a Sibling!

This might not be exactly what runs through your mind when you see that you have a very close match that you weren’t expecting.

The first two things I recommend when making this sort of discovery, after a few deep breaths, a walk, and a cup of tea, are:

  • Viewing what the vendor says
  • Using the DNAPainter Shared cM Relationship Chart

Let’s start with DNAPainter.

DNAPainter

DNAPainter provides a relationship chart, here, based on the values from the Shared cM Project.

You can either enter a cM amount or a percentage of shared DNA. I prefer the cM amount, but it doesn’t really matter.

I’ll enter 2241 cM from a known half-sibling match. To enter a percent, click on the green “enter %.”

As you can see, statistically speaking, this person is slightly more likely to be a half-sibling than they are to be a full sibling. In reality, they could be either.

Looking at the chart below, DNAPainter highlights the possible relationships from the perspective of “Self.”

The average of all the self-reported relationships is shown, on top, so 2613 for a full sibling. The range is shown below, so 1613-3488 for a full sibling.

In this case, there are several possibilities for two people who share 2241 cM of DNA.

I happen to know that these two people are half-siblings, but if I didn’t, it would be impossible to tell from this information alone.

The cM range for full siblings is 1613-3488, and the cM range for half-siblings is 1160-2436.

  • The lower part of the matching range, from 1160-1613 cM is only found in half-siblings.
  • The portion of the range from 1613-2436 cM can be either half or full siblings.
  • The upper part of the range, from 2436-3488 cM is only found in full siblings.

If your results fall into the center portion of the range, you’re going to need to utilize other tools. Fortunately, we have several.

If you’ve discovered something unexpected, you’ll want to verify using these tools, regardless. Use every tool available. Ranges are not foolproof, and the upper and lower 10% of the responses were removed as outliers. You can read more about the shared cM Project, here and here.

Furthermore, people may be reporting some half-sibling relationships as full sibling relationships, because they don’t expect to be half-siblings, so the ranges may be somewhat “off.”

Relationship Probability Calculator

Third-party matching database, GEDmatch, provides a Relationship Probability Calculator tool that is based on statistical probability methods without compiled user input. Both tools are free, and while I haven’t compared every value, both seem to be reasonably accurate, although they do vary somewhat, especially at the outer ends of the ranges.

When dealing with sibling matches, if you are in all four databases, GEDmatch is a secondary resource, but I will include GEDmatch when they have a unique tool as well as in the summary table. Some of your matches may be willing to upload to GEDmatch if the vendor where you match doesn’t provide everything you need and GEDmatch has a supplemental offering.

Next, let’s look at what the vendors say about sibling matches.

Vendors

Each of the major vendors reports sibling relationships in a slightly different way.

Sibling Matches at Ancestry

Ancestry reports sibling relationships as Sister or Brother, but they don’t say half or full.

If you click on the cM portion of the link, you’ll see additional detail, below

Ancestry tells you that the possible relationships are 100% “Sibling.” The only way to discern the difference between full and half is by what’s next.

If the ONLY relationship shown is Sibling at 100%, that can be interpreted to mean this person is a full sibling, and that a half-sibling or other relationship is NOT a possibility.

Ancestry never stipulates full or half.

The following relationship is a half-sibling at Ancestry.

Ancestry identifies that possible range of relationships as “Close Family to First Cousin” because of the overlaps we saw in the DNAPainter chart.

Clicking through shows that there is a range of possible relationships, and Ancestry is 100% sure the relationship is one of those.

DNAPainter agrees with Ancestry except includes the full-sibling relationship as a possibility for 1826 cM.

Sibling Matches at 23andMe

23andMe does identify full versus half-siblings.

DNAPainter disagrees with 23andMe and claims that anyone who shares 46.2% of their DNA is a parent/child.

However, look at the fine print. 23andMe counts differently than any of the other vendors, and DNAPainter relies on the Shared cM Project, which relies on testers entering known relationship matching information. Therefore, at any other vendor, DNAPainter is probably exactly right.

Before we understand how 23andMe counts, we need to understand about half versus fully identical segments.

To determine half or full siblings, 23andMe compares two things:

  1. The amount of shared matching DNA between two people
  2. Fully Identical Regions (FIR) of DNA compared to Half Identical Regions (HIR) of DNA to determine if any of your DNA is fully identical, meaning some pieces of you and your sibling’s DNA is exactly the same on both your maternal and paternal chromosomes.

Here’s an example on any chromosome – I’ve randomly selected chromosome 12. Which chromosome doesn’t matter, except for the X, which is different.

Your match isn’t broken out by maternal and paternal sides. You would simply see, on the chromosome browser, that you and your sibling match at these locations, above.

In reality, though, you have two copies of each chromosome, one from Mom and one from Dad, and so does your sibling.

In this example, Mom’s chromosome is visualized on top, and Dad’s is on the bottom, below, but as a tester, you don’t know that. All you know is that you match your sibling on all of those blue areas, above.

However, what’s actually happening in this example is that you are matching your sibling on parts of your mother’s chromosome and parts of your father’s chromosome, shown above as green areas

23andMe looks at both copies of your chromosome, the one you inherited from Mom, on top, and Dad, on the bottom, to see if you match your sibling on BOTH your mother’s and your father’s chromosomes in that location.

I’ve boxed the green matching areas in purple where you match your sibling fully, on both parents’ chromosomes.

If you and your sibling share both parents, you will share significant amounts of the same DNA on both copies of the same chromosomes, meaning maternal and paternal. In other words, full siblings share some purple fully identical regions (FIR) of DNA with each other, while half-siblings do not (unless they are also otherwise related) because half-siblings only share one parent with each other. Their DNA can’t be fully identical because they have a different parent that contributed the other copy of their chromosome.

Total Shared DNA Fully Identical DNA from Both Parents
Full Siblings ~50% ~25%
Half Siblings ~25% 0
  • Full siblings are expected to share about 50% of the same DNA. In other words, their DNA will match at that location. That’s all the green boxed locations, above.
  • Full siblings are expected to share about 25% of the same DNA from BOTH parents at the same location on BOTH copies of their chromosomes. These are fully identical regions and are boxed in purple, above.

You’ll find fully identical segments about 25% of the time in full siblings, but you won’t find fully identical segments in half-siblings. Please note that there are exceptions for ¾ siblings and endogamous populations.

You can view each match at 23andMe to see if you have any completely identical regions, shown in dark purple in the top comparison of full siblings. Half siblings are shown in the second example, with less total matching DNA and no FIR or completely identical regions.

Please note that your matching amount of DNA will probably be higher at 23andMe than at other companies because:

  • 23andMe includes the X chromosome in the match totals
  • 23andMe counts fully identical matching regions twice. For full siblings, that’s an additional 25%

Therefore, a full sibling with an X match will have a higher total cM at 23andMe than the same siblings elsewhere because not only is the X added into the total, the FIR match region is added a second time too.

Fully Identical Regions (FIR) and Half Identical Regions (HIR) at GEDmatch

At GEDMatch, you can compare two people to each other, with an option to display the matching information and a painted graphic for each chromosome that includes FIR and HIR.

If you need to know if you and a match share fully identical regions and you haven’t tested at 23andMe, you can both upload your DNA data file to GEDmatch and use their One to One Autosomal DNA Comparison.

On the following page, simply enter both kit numbers and accept the defaults, making sure you have selected one of the graphics options.

While GEDmatch doesn’t specifically tell you whether someone is a full or half sibling, you can garner additional information about the relationship based on the graphic at GEDmatch.

GEDMatch shows both half and fully identical regions.

The above match is between two full siblings using a 7 cM threshold. The blue on the bottom bar indicates a match of 7 cM or larger. Black means no match.

The green regions in the top bar indicate places where these two people carry the same DNA on both copies of their chromosome 1. This means that both people inherited the same DNA from BOTH parents on the green segments.

In the yellow regions, the siblings inherited the same DNA from ONE parent, but different DNA in that region from the other parent. They do match each other, just on one of their chromosomes, not both.

Without a tool like this to differentiate between HIR and FIR, you can’t tell if you’re matching someone on one copy of your chromosome, or on both copies.

In the areas marked with red on top, which corresponds to the black on the bottom band, these two siblings don’t match each other because they inherited different DNA from both parents in that region. The yellow in that region is too scattered to be significant.

Full siblings generally share a significant amount of FIR, or fully identical regions of DNA – about 25%.

Half siblings will share NO significant amount of FIR, although some will be FIR on very small, scattered green segments simply by chance, as you can see in the example, below.

This half-sibling match shares no segments large enough to be a match (7 cM) in the black section. In the blue matching section, only a few small green fragments of DNA match fully, which, based on the rest of that matching segment, must be identical by chance or misreads. There are no significant contiguous segments of fully identical DNA.

When dealing with full or half-siblings, you’re not interested in small, scattered segments of fully identical regions, like those green snippets on chromosome 6, but in large contiguous sections of matching DNA like the chromosome 1 example.

GEDmatch can help when you match when a vendor does not provide FIR/HIR information, and you need additional assistance.

Next, let’s look at full and half-siblings at FamilyTreeDNA

Sibling Matches at FamilyTreeDNA

FamilyTreeDNA does identify full siblings.

Relationships other than full siblings are indicated by a range. The two individuals below are both half-sibling matches to the tester.

The full range when mousing over the relationship ranges is shown below.

DNAPainter agrees except also gives full siblings as an option for the two half-siblings.

FamilyTreeDNA also tells you if you have an X match and the size of your X match.

We will talk about X matching in a minute, which, when dealing with sibling identification, can turn out to be very important.

Sibling Matches at MyHeritage

MyHeritage indicates brother or sister for full siblings

MyHeritage provides other “Estimated relationships” for matches too small to be full siblings.

DNAPainter’s chart agrees with this classification, except adds additional relationship possibilities.

Be sure to review all of the information provided by each vendor for close relationships.

View Close Known Relationships

The next easiest step to take is to compare your full or half-sibling match to known close family members from your maternal and paternal sides, respectively. The closer the family members, the better.

It’s often not possible to determine if someone is a half sibling or a full sibling by centiMorgans (cMs) alone, especially if you’re searching for unknown family members.

Let’s start with the simplest situation first.

Let’s say both of your parents have tested, and of course, you match both of them as parents.

Your new “very close match” is in the sibling range.

The first thing to do at each vendor is to utilize that vendor’s shared matches tool and see whether your new match matches one parent, or both.

Here’s an example.

Close Relationships at FamilyTreeDNA

This person has a full sibling match, but let’s say they don’t know who this is and wants to see if their new sibling matches one or both of their parents.

Select the match by checking the box to the left of the match name, then click on the little two-person icon at far right, which shows “In Common” matches

You can see on the resulting shared match list that both of the tester’s parents are shown on the shared match list.

Now let’s make this a little more difficult.

No Parents, No Problem

Let’s say neither of your parents has tested.

If you know who your family is and can identify your matches, you can see if the sibling you match matches other close relatives on both or either side of your family.

You’ll want to view shared matches with your closest known match on both sides of your tree, beginning with the closest first. Aunts, uncles, first cousins, etc.

You will match all of your family members through second cousins, and 90% of your third cousins. You can view additional relationship percentages in the article, How Much of Them is in You?.

I recommend, for this matching purpose, to utilize 2nd cousins and closer. That way you know for sure if you don’t share them as a match with your sibling, it’s because the sibling is not related on that side of the family, not because they simply don’t share any DNA due to their distance.

In this example, you have three sibling matches. Based on your and their matches to the same known first and second cousins, you can see that:

  • Sibling 1 is your full sibling, because you both match the same maternal and paternal first and second cousins
  • Sibling 2 is your paternal half-sibling because you both match paternal second cousins and closer, but not maternal cousins.
  • Sibling 3 is your maternal half-sibling because you both match maternal second cousins and closer, but not paternal cousins.

Close Relationships at Ancestry

Neither of my parents have tested, but my first cousin on my mother’s side has. Let’s say I have a suspected sibling or half-sibling match, so I click on the match’s name, then on Shared Matches.

Sure enough, my new match also matches my first cousin that I’ve labeled as “on my mother’s side.”

If my new match in the sibling range also matches my second cousins or closer on my father’s side, the new match is a full sibling, not a half-sibling.

Close Relationships at MyHeritage

Comparing my closest match provided a real surprise. I wonder if I’ve found a half-sibling to my mother.

Now, THIS is interesting.

Hmmm. More research is needed, beginning with the age of my match. MyHeritage provides ages if the MyHeritage member authorizes that information to be shared.

Close Relationships at 23andMe

Under DNA Relatives, click on your suspected sibling match, then scroll down and select “Find Relatives in Common.”

The Relatives in Common list shows people that match both of you.

The first common match is very close and a similar relationship to my closest match on my father’s side. This would be expected of a sibling. I have no common matches with this match to anyone on my mother’s side, so they are only related on my father’s side. Therefore they are a paternal half-sibling, not a full sibling.

More Tools Are Available

Hopefully, by now, you’ve been able to determine if your mystery match is a sibling, and if so, if they are a half or full sibling, and through which parent.

We have some additional tools that are relevant and can be very informative in some circumstances. I suggest utilizing these tools, even if you think you know the answer.

In this type of situation, there’s no such thing as too much information.

X Matching

X matching, or lack thereof, may help you determine how you are related to someone.

There are two types of autosomal DNA. The X chromosome versus chromosomes 1-22. The X chromosome (number 23) has a unique inheritance path that distinguishes it from your other chromosomes.

The X chromosome inheritance path also differs between men and women.

Here’s my pedigree chart in fan form, highlighting the ancestors who may have contributed a portion of their X chromosome to me. In the closest generation, this shows that I inherited an X chromosome from both of my parents, and who in each of their lines could have contributed an X to them.

The white or uncolored positions, meaning ancestors, cannot contribute any portion of an X chromosome to me based on how the X chromosome is inherited.

You’ll notice that my father inherited none of his X chromosome from any of his paternal ancestors, so of course, I can’t inherit what he didn’t inherit. There are a very limited number of ancestors on my father’s side whom I can inherit any portion of an X chromosome from.

Men receive their Y chromosome from their fathers, so men ONLY receive an X chromosome from their mother.

Therefore, men MUST pass their mother’s X chromosome on to their female offspring because they don’t have any other copy of the X chromosome to pass on.

Men pass no X chromosome to sons.

We don’t need to worry about a full fan chart when dealing with siblings and half-siblings.

We only need to be concerned with the testers plus one generation (parents) when utilizing the X chromosome in sibling situations.

These two female Disney Princesses, above, are full siblings, and both inherited an X chromosome from BOTH their mother and father. However, their father only has one X (red) chromosome to give them, so the two females MUST match on the entire red X chromosome from their father.

Their mother has two X chromosomes, green and black, to contribute – one from each of her parents.

The full siblings, Melody, and Cinderella:

  • May have inherited some portion of the same green and black X chromosomes from their mother, so they are partial matches on their mother’s X chromosome.
  • May have inherited the exact same full X chromosome from their mother (both inherited the entire green or both inherited the entire black), so they match fully on their mother’s X chromosome.
  • May have inherited the opposite X from different maternal grandparents. One inherited the entire green X and one inherited the entire black X, so they don’t match on their mother’s X chromosome.

Now, let’s look at Cinderella, who matches Henry.

This female and male full sibling match can’t share an X chromosome on the father’s side, because the male’s father doesn’t contribute an X chromosome to him. The son, Henry, inherited a Y chromosome instead from his father, which is what made them males.

Therefore, if a male and female match on the X chromosome, it MUST be through HIS mother, but could be through either of her parents. In a sibling situation, an X match between a male and female always indicates the mother.

In the example above, the two people share both of their mother’s X chromosomes, so are definitely (at least) maternally related. They could be full siblings, but we can’t determine that by the X chromosome in this situation, with males.

However, if the male matches the female on HER father’s X chromosome, there a different message, example below.

You can see that the male is related to the female on her father’s side, where she inherited the entire magenta X chromosome. The male inherited a portion of the magenta X chromosome from his mother, so these two people do have an X match. However, he matches on his mother’s side, and she matches on her father’s side, so that’s clearly not the same parent.

  • These people CAN NOT be full siblings because they don’t match on HER mother’s side too, which would also be his mother’s side if they were full siblings.
  • They cannot be maternal half-siblings because their X DNA only matches on her father’s side, but they wouldn’t know that unless she knew which side was which based on share matches.
  • They cannot be paternal half-siblings because he does not have an X chromosome from his father.

They could, however, be uncle/aunt-niece/nephew or first cousins on his mother’s side and her father’s side. (Yes, you’re definitely going to have to read this again if you ever need male-female X matching.)

Now, let’s look at X chromosome matching between two males. It’s a lot less complicated and much more succinct.

Neither male has inherited an X chromosome from their father, so if two males DO match on the X, it MUST be through their mother. In terms of siblings, this would mean they share the same mother.

However, there is one slight twist. In the above example, you can see that the men inherited a different proportion of the green and black X chromosomes from their common mother. However, it is possible that the mother could contribute her entire green X chromosome to one son, Justin in this example, and her entire black X chromosome to Henry.

Therefore, even though Henry and Justin DO share a mother, their X chromosome would NOT match in this scenario. This is rare but does occasionally happen.

Based on the above examples, the X chromosome may be relevant in the identification of full or half siblings based on the sexes of the two people who otherwise match at a level indicating a full or half-sibling relationship.

Here’s a summary chart for sibling X matching.

X Match Female Male
Female Will match on shared father’s full X chromosome, mother’s X is the same rules as chromosomes 1-22 Match through male’s mother, but either of female’s parents. If the X match is not through the female’s mother, they are not full siblings nor maternal half-siblings. They cannot have an X match through the male’s father. They are either full or half-siblings through their mother if they match on both of their mother’s side. If they match on his mother’s side, and her father’s side, they are not siblings but could be otherwise closely related.
Male Match through male’s mother, but either of female’s parents. If the X match is not through the female’s mother, they are not full siblings nor maternal half-siblings. They cannot have an X match through the male’s father. They are either full or half-siblings through their mother if they match on both or their mother’s side. If they match on his mother’s side, and her father’s side, they are not siblings but could be otherwise closely related. Both males are related on their mother’s side – either full or half-siblings.

Here’s the information presented in a different way.

DOES match X summary:

  • If a male DOES match a female on the X, he IS related to her through HIS mother’s side, but could match her on her mother or father’s side. If their match is not through her mother, then they are not full siblings nor maternal half-siblings. They cannot match through his father, so they cannot be paternal half-siblings.
  • If a female DOES match a female on the X, they could be related on either side and could be full or half-siblings.
  • If a male DOES match a male on the X, they ARE both related through their mother. They may also be related on their father’s side, but the X does not inform us of that.

Does NOT match X summary:

  • If a male does NOT match a female on the X, they are NOT related through HIS mother and are neither full siblings nor maternal half-siblings. Since a male does not have an X chromosome from his father, they cannot be paternal half-siblings based on an X match.
  • If a male does NOT match a male, they do NOT share a mother.
  • If a female does NOT match another female on the X, they are NOT full siblings and are NOT half-siblings on their paternal side. Their father only has one X chromosome, and he would have given the same X to both daughters.

Of the four autosomal vendors, only 23andMe and FamilyTreeDNA report X chromosome results and matching, although the other two vendors, MyHeritage and Ancestry, include the X in their DNA download file so you can find X matches with those files at either FamilyTreeDNA or GEDMatch if your match has or will upload their file to either of those vendors. I wrote step-by-step detailed download/upload instructions, here.

X Matching at FamilyTreeDNA

In this example from FamilyTreeDNA, the female tester has discovered two half-sibling matches, both through her father. In the first scenario, she matches a female on the full X chromosome (181 cM). She and her half-sibling MUST share their father’s entire X chromosome because he only had one X, from his mother, to contribute to both of his daughters.

In the second match to a male half-sibling, our female tester shares NO X match because her father did not contribute an X chromosome to his son.

If we didn’t know which parents these half-sibling matches were through, we can infer from the X matching alone that the male is probably NOT through the mother.

Then by comparing shared matches with each sibling, Advanced Matches, or viewing the match Matrix, we can determine if the siblings match each other and are from the same or different sides of the family.

Under Additional Tests and Tools, Advanced Matching, FamilyTreeDNA provides an additional tool that can show only X matches combined with relationships.

Of course, you’ll need to view shared matches to see which people match the mother and/or match the father.

To see who matches each other, you’ll need to use the Matrix tool.

At FamilyTreeDNA, the Matrix, located under Autosomal DNA Results and Tools, allows you to select your matches to see if they also match each other. If you have known half-siblings, or close relatives, this is another way to view relationships.

Here’s an example using my father and two paternal half-siblings. We can see that the half-siblings also match each other, so they are (at least) half-siblings on the paternal side too.

If they also matched my mother, we would be full siblings, of course.

Next, let’s use Y DNA and mitochondrial DNA.

Y DNA and Mitochondrial DNA

In addition to autosomal DNA, we can utilize Y DNA and mitochondrial DNA (mtDNA) in some cases to identify siblings or to narrow or eliminate relationship possibilities.

Given that Y DNA and mitochondrial DNA both have distinctive inheritance paths, full and half-siblings will, or will not, match under various circumstances.

Y DNA

Y DNA is passed intact from father to son, meaning it’s not admixed with any of the mother’s DNA. Daughters do not inherit Y DNA from their father, so Y DNA is only useful for male-to-male comparisons.

Two types of Y DNA are used for genealogy, STR markers for matching, and haplogroups, and both are equally powerful in slightly different ways.

Y DNA at FamilyTreeDNA

Men can order either 37 or 111 STR marker tests, or the BIg Y which provides more than 700 markers and more. FamilyTreeDNA is the only one of the vendors to offer Y DNA testing that includes STR markers and matching between men.

Men who order these tests will be compared for matching on either 37, 111 or 700 STR markers in addition to SNP markers used for haplogroup identification and assignment.

Fathers will certainly match their sons, and paternal line brothers will match each other, but they will also match people more distantly related.

However, if two men are NOT either full or half siblings on the paternal side, they won’t match at 111 markers.

If two men DON’T match, especially at high marker levels, they likely aren’t siblings. The word “likely” is in there because, very occasionally, a large deletion occurs that prevents STR matching, especially at lower levels.

Additionally, men who take the 37 or 111 marker test also receive an estimated haplogroup at a high level for free, without any additional testing.

However, if men take the Big Y-700 test, they not only will (or won’t) match on up to 700 STR markers, they will also receive a VERY refined haplogroup via SNP marker testing that is often even more sensitive in terms of matching than STR markers. Between these two types of markers, Y DNA testing can place men very granularly in relation to other men.

Men can match in two ways on Y DNA, and the results are very enlightening.

If two men match on BOTH their most refined haplogroup (Big Y test) AND STR markers, they could certainly be siblings or father/son. They could also be related on the same line for another reason, such as known or unknown cousins or closer relationships like uncle/nephew. Of course, Y DNA, in addition to autosomal matching, is a powerful combination.

Conversely, if two men don’t have a similar or close haplogroup, they are not a father and son or paternal line siblings.

FamilyTreeDNA offers both inexpensive entry-level testing (37 and 111 markers) and highly refined advanced testing of most of the Y chromosome (Big Y-700), so haplogroup assignments can vary widely based on the test you take. This makes haplogroup matching and interpretation a bit more complex.

For example, haplogroups R-M269 and I-BY14000 are not related in thousands of years. One is haplogroup R, and one is haplogroup I – completely different branches of the Y DNA tree. These two men won’t match on STR markers or their haplogroup.

However, because FamilyTreeDNA provides over 50,000 different haplogroups, or tree branches, for Big Y testers, and they provide VERY granular matching, two father/son or sibling males who have BOTH tested at the Big Y-700 level will have either the exact same haplogroup, or at most, one branch difference on the tree if a mutation occurred between father and son.

If both men have NOT tested at the Big Y-700 level, their haplogroups will be on the same branch. For example, a man who has only taken a 37/111 marker STR test may be estimated at R-M269, which is certainly accurate as far as it goes.

His sibling who has taken a Big Y test will be many branches further downstream on the tree – but on the same large haplogroup R-M269 branch. It’s essential to pay attention to which tests a Y DNA match has taken when analyzing the match.

The beauty of the two kinds of tests is that even if one haplogroup is very general due to no Big Y test, their STR markers should still match. It’s just that sometimes this means that one hand is tied behind your back.

Y DNA matching alone can eliminate the possibility of a direct paternal line connection, but it cannot prove siblingship or paternity alone – not without additional information.

The Advanced Matching tool will provide a list of matches in all categories selected – in this case, both the 111 markers and the Family Finder test. You can see that one of these men is the father of the tester, and one is the full sibling.

You can view haplogroup assignments on the public Y DNA tree, here. I wrote about using the public tree, here.

In addition, recently, FamilyTreeDNA launched the new Y DNA Discover tool, which explains more about haplogroups, including their ages and other fun facts like migration paths along with notable and ancient connections. I wrote about using the Discover tool, here.

Y DNA at 23andMe

Testers receive a base haplogroup with their autosomal test. 23andMe tests a limited number of Y DNA SNP locations, but they don’t test many, and they don’t test STR markers, so there is no Y DNA matching and no refined haplogroups.

You can view the haplogroups of your matches. If your male sibling match does NOT share the same haplogroup, the two men are not paternal line siblings. If two men DO share the same haplogroup, they MIGHT be paternal siblings. They also might not.

Again, autosomal close matching plus haplogroup comparisons include or exclude paternal side siblings for males.

Paternal side siblings at 23andMe share the same haplogroup, but so do many other people. These two men could be siblings. The haplogroups don’t exclude that possibility. If the haplogroups were different, that would exclude being either full or paternal half-siblings.

Men can also compare their mitochondrial DNA to eliminate a maternal relationship.

These men are not full siblings or maternal half-siblings. We know, unquestionably, because their mitochondrial haplogroups don’t match.

23andMe also constructs a genetic tree, but often struggles with close relative placement, especially when half-relationships are involved. I do not recommend relying on the genetic tree in this circumstance.

Mitochondrial DNA

Mitochondrial DNA is passed from mothers to all of their children, but only females pass it on. If two people, males or females, don’t match on their mitochondrial DNA test, with a couple of possible exceptions, they are NOT full siblings, and they are NOT maternal half-siblings.

Mitochondrial DNA at 23andMe

23andMe provides limited, base mitochondrial haplogroups, but no matching. If two people don’t have the same haplogroup at 23andMe, they aren’t full or maternal siblings, as illustrated above.

Mitochondrial DNA at FamilyTreeDNA

FamilyTreeDNA provides both mitochondrial matching AND a much more refined haplogroup. The full sequence test (mtFull), the only version sold today, is essential for reliable comparisons.

Full siblings or maternal half-siblings will always share the same haplogroup, regardless of their sex.

Generally, a full sibling or maternal half-sibling match will match exactly at the full mitochondrial sequence (FMS) level with a genetic distance of zero, meaning fully matching and no mismatching mutations.

There are rare instances where maternal siblings or even mothers and children do not match exactly, meaning they have a genetic distance of greater than 0, because of a mutation called a heteroplasmy.

I wrote about heteroplasmies, here.

Like Y DNA, mitochondrial DNA cannot identify a sibling or parental relationship without additional evidence, but it can exclude one, and it can also provide much-needed evidence in conjunction with autosomal matching. The great news is that unlike Y DNA, everyone has mitochondrial DNA and it comes directly from their mother.

Once again, FamilyTreeDNA’s Advanced Matching tool provides a list of people who match you on both your mitochondrial DNA test and the Family Finder autosomal test, including transfers/uploads, and provides a relationship.

You can see that our tester matches both a full sibling and their mother. Of course, a parent/child match could mean that our tester is a female and one of her children, of either sex, has tested.

Below is an example of a parent-child match that has experienced a heteroplasmy.

Based on the comparison of both the mitochondrial DNA test, plus the autosomal Family Finder test, you can verify that this is a close family relationship.

You can also eliminate potential relationships based on the mitochondrial DNA inheritance path. The mitochondrial DNA of full siblings and maternal half-siblings will always match at the full sequence and haplogroup level, and paternal half-siblings will never match. If paternal half-siblings do match, it’s happenstance or because of a different reason.

Sibling Summary and Checklist

I’ve created a quick reference checklist for you to use when attempting to determine whether or not a match is a sibling, and, if so, whether they are half or full siblings. Of course, these tools are in addition to the DNAPainter Shared cM Tool and GEDmatch’s Relationship Predictor Calculator.

FamilyTreeDNA Ancestry 23andMe MyHeritage GEDmatch
Matching Yes Yes Yes Yes Yes
Shared Matches Yes – In Common With Yes – Shared Matches Yes – Relatives in Common Yes – Review DNA Match Yes – People who match both or 1 of 2 kits
Relationship Between Shared Matches No No No Yes, under shared match No
Matches Match Each Other* Yes, Matrix No Yes, under “View DNA details,” then, “compare with more relatives” Partly, through triangulation Yes, can match any kits
Full Siblings Yes Sibling, implies full Yes Brother, Sister, means full No
Half Siblings Sibling, Uncle/Aunt-Niece/Nephew, Grandparent-Grandchild Close Family – 1C Yes Half sibling, aunt/uncle-niece-nephew No
Fully Identical Regions (FIR) No No Yes No Yes
Half Identical Regions (HIR) No No Yes No Yes
X matching Yes No Yes No Yes
Unusual Reporting or Anomalies No No, Timber is not used on close relationships X match added into total, FIR added twice No Matching amount can vary from vendors
Y DNA Yes, STRs, refined haplogroups, matching No High-level haplogroup only, no matching No No, only if tester enters haplogroup manually
Mitochondrial DNA Yes, full sequence, matching, refined haplogroup No High-level haplogroup only, no matching No No, only if tester enters haplogroup manually
Combined Tools (Autosomal, X, Y, mtDNA) Yes No No No No

*Autoclusters through Genetic Affairs show cluster relationships of matches to the tester and to each other, but not all matches are included, including close matches. While this is a great tool, it’s not relevant for determining close and sibling relationships. See the article, AutoClustering by Genetic Affairs, here.

Additional Resources

Some of you may be wondering how endogamy affects sibling numbers.

Endogamy makes almost everything a little more complex. I wrote about endogamy and various ways to determine if you have an endogamous heritage, here.

Please note that half-siblings with high cM matches also fall into the range of full siblings (1613-3488), with or without endogamy. This may be, but is not always, especially pronounced in endogamous groups.

As another resource, I wrote an earlier article, Full or Half Siblings, here, that includes some different examples.

Strategy

You have a lot of quills in your quiver now, and I wish you the best if you’re trying to unravel a siblingship mystery.

You may not know who your biological family is, or maybe your sibling doesn’t know who their family is, but perhaps your close relatives know who their family is and can help. Remember, the situation that has revealed itself may be a shock to everyone involved.

Above all, be kind and take things slow. If your unexpected sibling match becomes frightened or overwhelmed, they may simply check out and either delete their DNA results altogether or block you. They may have that reaction before you have a chance to do anything.

Because of that possibility, I recommend performing your analysis quickly, along with taking relevant screenshots before reaching out so you will at least have that much information to work with, just in case things go belly up.

When you’re ready to make contact, I suggest beginning by sending a friendly, short, message saying that you’ve noticed that you have a close match (don’t say sibling) and asking what they know about their family genealogy – maybe ask who their grandparents are or if they have family living in the area where you live. I recommend including a little bit of information about yourself, such as where you were born and are from.

I also refrain from using the word adoption (or similar) in the beginning or giving too much detailed information, because it sometimes frightens people, especially if they know or discover that there’s a painful or embarrassing family situation.

And, please, never, ever assume the worst of anyone or their motives. They may be sitting at their keyboard with the same shocked look on their face as you – especially if they have, or had, no idea. They may need space and time to reach a place of acceptance. There’s just nothing more emotionally boat-capsizing in your life than discovering intimate and personal details about your parents, one or both, especially if that discovery is disappointing and image-altering.

Or, conversely, your sibling may have been hoping and waiting just for you!

Take a deep breath and let me know how it goes!

Please feel free to share this article with anyone who could benefit.

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DNA: In Search of…Signs of Endogamy

This is the fourth in our series of articles about searching for unknown close family members, specifically; parents, grandparents, or siblings. However, these same techniques can be applied by genealogists to ancestors further back in time as well.

In this article, we discuss endogamy – how to determine if you have it, from what population, and how to follow the road signs.

After introductions, we will be covering the following topics:

  • Pedigree collapse and endogamy
  • Endogamous groups
  • The challenge(s) of endogamy
  • Endogamy and unknown close relatives (parents, grandparents)
  • Ethnicity and Populations
  • Matches
  • AutoClusters
  • Endogamous Relationships
  • Endogamous DNA Segments
  • “Are Your Parents Related?” Tool
  • Surnames
  • Projects
  • Locations
  • Y DNA, Mitochondrial DNA, and Endogamy
  • Endogamy Tools Summary Tables
    • Summary of Endogamy Tools by Vendor
    • Summary of Endogamous Populations Identified by Each Tool
    • Summary of Tools to Assist People Seeking Unknown Parents and Grandparents

What Is Endogamy and Why Does It Matter?

Endogamy occurs when a group or population of people intermarry among themselves for an extended period of time, without the introduction of many or any people from outside of that population.

The effect of this continual intermarriage is that the founders’ DNA simply gets passed around and around, eventually in small segments.

That happens because there is no “other” DNA to draw from within the population. Knowing or determining that you have endogamy helps make sense of DNA matching patterns, and those patterns can lead you to unknown relatives, both close and distant.

This Article

This article serves two purposes.

  • This article is educational and relevant for all researchers. We discuss endogamy using multiple tools and examples from known endogamous people and populations.
  • In order to be able to discern endogamy when we don’t know who our parents or grandparents are, we need to know what signs and signals to look for, and why, which is based on what endogamy looks like in people who know their heritage.

There’s no crystal ball – no definitive “one-way” arrow, but there are a series of indications that suggest endogamy.

Depending on the endogamous population you’re dealing with, those signs aren’t always the same.

If you’re sighing now, I understand – but that’s exactly WHY I wrote this article.

We’re covering a lot of ground, but these road markers are invaluable diagnostic tools.

I’ve previously written about endogamy in the articles:

Let’s start with definitions.

Pedigree Collapse and Endogamy

Pedigree collapse isn’t the same as endogamy. Pedigree collapse is when you have ancestors that repeat in your tree.

In this example, the parents of our DNA tester are first cousins, which means the tester shares great-grandparents on both sides and, of course, the same ancestors from there on back in their tree.

This also means they share more of those ancestors’ DNA than they would normally share.

John Smith and Mary Johnson are both in the tree twice, in the same position as great-grandparents. Normally, Tester Smith would carry approximately 12.5% of each of his great-grandparents’ DNA, assuming for illustration purposes that exactly 50% of each ancestor’s DNA is passed in each generation. In this case, due to pedigree collapse, 25% of Tester Smith’s DNA descends from John Smith, and another 25% descends from Mary Johnson, double what it would normally be. 25% is the amount of DNA contribution normally inherited from grandparents, not great-grandparents.

While we may find first cousin marriages a bit eyebrow-raising today, they were quite common in the past. Both laws and customs varied with the country, time, social norms, and religion.

Pedigree Collapse and Endogamy is NOT the Same

You might think that pedigree collapse and endogamy is one and the same, but there’s a difference. Pedigree collapse can lead to endogamy, but it takes more than one instance of pedigree collapse to morph into endogamy within a population. Population is the key word for endogamy.

The main difference is that pedigree collapse occurs with known ancestors in more recent generations for one person, while endogamy is longer-term and systemic in a group of people.

Picture a group of people, all descended from Tester Smith’s great-grandparents intermarrying. Now you have the beginnings of endogamy. A couple hundred or a few hundred years later, you have true endogamy.

In other words, endogamy is pedigree collapse on a larger scale – think of a village or a church.

My ancestors’ village of Schnait, in Germany, is shown above in 1685. One church and maybe 30 or 40 homes. According to church and other records, the same families had inhabited this village, and region, for generations. It’s a sure bet that both pedigree collapse and endogamy existed in this small community.

If pedigree collapse happens over and over again because there are no other people within the community to marry, then you have endogamy. In other words, with endogamy, you assuredly DO have historical pedigree collapse, generally back in time, often before you can identify those specific ancestors – because everyone descends from the same set of founders.

Endogamy Doesn’t Necessarily Indicate Recent Pedigree Collapse

With deep, historic endogamy, you don’t necessarily have recent pedigree collapse, and in fact, many people do not. Jewish people are a good example of this phenomenon. They shared ancestors for hundreds or thousands of years, depending on which group we are referring to, but in recent, known, generations, many Jewish people aren’t related. Still, their DNA often matches each other.

The good news is that there are telltale signs and signals of endogamy.

The bad news is that not all of these are obvious, meaning as an aid to people seeking clues about unknown close relatives, and other “signs” aren’t what they are believed to be.

Let’s step through each endogamy identifier, or “hint,” and then we will review how we can best utilize this information.

First, let’s take a look at groups that are considered to be endogamous.

Endogamous Groups

Jewish PeopleSpecifically groups that were isolated from other groups of Jewish (and other) people; Ashkenazi (Germany, Northern France, and diaspora), Sephardic (Spanish, Iberia, and diaspora), Mizrahi (Israel, Middle Eastern, and diaspora,) Ethiopian Jews, and possibly Jews from other locations such as Mountain Jews from Kazakhstan and the Caucasus.

AcadiansDescendants of about 60 French families who settled in “Acadia” beginning about 1604, primarily on the island of Nova Scotia, and intermarried among themselves and with the Mi’kmaq people. Expelled by the English in 1755, they were scattered in groups to various diasporic regions where they continued to intermarry and where their descendants are found today. Some Acadians became the Cajuns of Louisiana.

Anabaptist Protestant FaithsAmish, Mennonite, and Brethren (Dunkards) and their offshoots are Protestant religious sects founded in Europe in the 14th, 15th, and 16th centuries on the principle of baptizing only adults or people who are old enough to choose to follow the faith, or rebaptizing people who had been previously baptized as children. These Anabaptist faiths tend to marry within their own group or church and often expel those who marry outside of the faith. Many emigrated to the American colonies and elsewhere, seeking religious freedom. Occasionally those groups would locate in close proximity and intermarry, but not marry outside of other Anabaptist denominations.

Native American (Indigenous) People – all indigenous peoples found in North and South America before European colonization descended from a small number of original founders who probably arrived at multiple times.

Indigenous Pacific Islanders – Including indigenous peoples of Australia, New Zealand, and Hawaii prior to colonization. They are probably equally as endogamous as Native American people, but I don’t have specific examples to share.

Villages – European or other villages with little inflow or whose residents were restricted from leaving over hundreds of years.

Other groups may have significant multiple lines of pedigree collapse and therefore become endogamous over time. Some people from Newfoundland, French Canadians, and Mormons (Church of Jesus Christ of Latter-Day Saints) come to mind.

Endogamy is a process that occurs over time.

Endogamy and Unknown Relatives

If you know who your relatives are, you may already know you’re from an endogamous population, but if you’re searching for close relatives, it’s helpful to be able to determine if you have endogamous heritage, at least in recent generations.

If you know nothing about either parent, some of these tools won’t help you, at least not initially, but others will. However, as you add to your knowledge base, the other tools will become more useful.

If you know the identity of one parent, this process becomes at least somewhat easier.

In future articles, we will search specifically for parents and each of your four grandparents. In this article, I’ll review each of the diagnostic tools and techniques you can use to determine if you have endogamy, and perhaps pinpoint the source.

The Challenge

People with endogamous heritage are related in multiple, unknown ways, over many generations. They may also be related in known ways in recent generations.

If both of your parents share the SAME endogamous culture or group of relatives:

  • You may have significantly more autosomal DNA matches than people without endogamy, unless that group of people is under-sampled. Jewish people have significantly more matches, but Native people have fewer due to under-sampling.
  • You may experience a higher-than-normal cM (centiMorgan) total for estimated relationships, especially more distant relationships, 3C and beyond.
  • You will have many matches related to you on both your maternal and paternal sides.
  • Parts of your autosomal DNA will be the same on both your mother’s and father’s sides, meaning your DNA will be fully identical in some locations. (I’ll explain more in a minute.)

If either (or both) of your parents are from an endogamous population, you:

  • Will, in some cases, carry identifying Y and mitochondrial DNA that points to a specific endogamous group. This is true for Native people, can be true for Jewish people and Pacific Islanders, but is not true for Anabaptist people.

One Size Does NOT Fit All

Please note that there is no “one size fits all.”

Each or any of these tools may provide relevant hints, depending on:

  • Your heritage
  • How many other people have tested from the relevant population group
  • How many close or distant relatives have tested
  • If your parents share the same heritage
  • Your unique DNA inheritance pattern
  • If your parents, individually, were fully endogamous or only partly endogamous, and how far back generationally that endogamy occurred

For example, in my own genealogy, my maternal grandmother’s father was Acadian on his father’s side. While I’m not fully endogamous, I have significantly more matches through that line proportionally than on my other lines.

I have Brethren endogamy on my mother’s side via her paternal grandmother.

Endogamous ancestors are shown with red stars on my mother’s pedigree chart, above. However, please note that her maternal and paternal endogamous ancestors are not from the same endogamous population.

However, I STILL have fewer matches on my mother’s side in total than on my father’s side because my mother has recent Dutch and recent German immigrants which reduces her total number of matches. Neither of those lines have had as much time to produce descendants in the US, and Europe is under-sampled when compared with the US where more people tend to take DNA tests because they are searching for where they came from.

My father’s ancestors have been in the US since it was a British Colony, and I have many more cousins who have tested on his side than mother’s.

If you looked at my pedigree chart and thought to yourself, “that’s messy,” you’d be right.

The “endogamy means more matches” axiom does not hold true for me, comparatively, between my parents – in part because my mother’s German and Dutch lines are such recent immigrants.

The number of matches alone isn’t going to tell this story.

We are going to need to look at several pieces and parts for more information. Let’s start with ethnicity.

Ethnicity and Populations

Ethnicity can be a double-edged sword. It can tell you exactly nothing you couldn’t discern by looking in the mirror, or, conversely, it can be a wealth of information.

Ethnicity reveals the parts of the world where your ancestors originated. When searching for recent ancestors, you’re most interested in majority ethnicity, meaning the 50% of your DNA that you received from each of your parents.

Ethnicity results at each vendor are easy to find and relatively easy to understand.

This individual at FamilyTreeDNA is 100% Ashkenazi Jewish.

If they were 50% Jewish, we could then estimate, and that’s an important word, that either one of their parents was fully Jewish, and not the other, or that two of their grandparents were Jewish, although not necessarily on the same side.

On the other hand, my mother’s ethnicity, shown below, has nothing remarkable that would point to any majority endogamous population, yet she has two.

The only hint of endogamy from ethnicity would be her ~1% Americas, and that isn’t relevant for finding close relatives. However, minority ancestry is very relevant for identifying Native ancestors, which I wrote about, here.

You can correlate or track your ethnicity segments to specific ancestors, which I discussed in the article, Native American & Minority Ancestors Identified Using DNAPainter Plus Ethnicity Segments, here.

Since I wrote that article, FamilyTreeDNA has added the feature of ethnicity or population Chromosome Painting, based on where each of your populations fall on your chromosomes.

In this example on chromosome 1, I have European ancestry (blue,) except for the pink Native segment, which occurs on the following segment in the same location on my mother’s chromosome 1 as well.

Both 23andMe, and FamilyTreeDNA provide chromosome painting AND the associated segment information so you can identify the relevant ancestors.

Ancestry is in the process of rolling out an ethnicity painting feature, BUT, it has no segment or associated matching information. While it’s interesting eye candy, it’s not terribly useful beyond the ethnicity information that Ancestry already provides. However, Jonny Perl at DNAPainter has devised a way to estimate Ancestry’s start and stop locations, here. Way to go Jonny!

Now all you need to do is convince your Ancestry matches to upload their DNA file to one of the three databases, FamilyTreeDNA, MyHeritage, and GEDMatch, that accept transfers, aka uploads. This allows matching with segment data so that you can identify who matches you on that segment, track your ancestors, and paint your ancestral segments at DNAPainter.

I provided step-by-step instructions, here, for downloading your raw DNA file from each vendor in order to upload the file to another vendor.

Ethnicity Sides

Three of the four DNA testing vendors, 23andMe, FamilyTreeDNA, and recently, Ancestry, attempt to phase your ethnicity DNA, meaning to assign it to one parental “side” or the other – both in total and on each chromosome.

Here’s Ancestry’s SideView, where your DNA is estimated to belong to parent 1 and parent 2. I detailed how to determine which side is which, here, and while that article was written specifically pertaining to Ancestry’s SideView, the technique is relevant for all the vendors who attempt to divide your DNA into parents, a technique known as phasing.

I say “attempt” because phasing may or may not be accurate, meaning the top chromosome may not always be parent 1, and the bottom chromosome may not always be chromosome 2.

Here’s an example at 23andMe.

See the two yellow segments. They are both assigned as Native. I happen to know one is from the mother and one is from the father, yet they are both displayed on the “top” chromosome, which one would interpret to be the same parent.

I am absolutely positive this is not the case because this is a close family member, and I have the DNA of the parent who contributed the Native segment on chromosome 1, on the top chromosome. That parent does not have a Native segment on chromosome 2 to contribute. So that Native segment had to be contributed by the other parent, but it’s also shown on the top chromosome.

The DNA segments circled in purple belong together on the same “side” and were contributed to the tester by the same parent. The Native segment on chromosome 2 abuts a purple African segment, suggesting perhaps that the ancestor who contributed that segment was mixed between those ethnicities. In the US, that suggests enslavement.

The other African segments, circled, are shown on the second chromosome in each pair.

To be clear, parent 1 is not assigned by the vendors to either mother or father and will differ by person. Your parent 1, or the parent on the top chromosome may be your mother and another person’s parent 1 may be their father.

As shown in this example, parents can vary by chromosome, a phenomenon known as “strand swap.” Occasionally, the DNA can even be swapped within a chromosome assignment.

You can, however, get an idea of the division of your DNA at any specific location. As shown above, you can only have a maximum of two populations of DNA on any one chromosome location.

In our example above, this person’s majority ancestry is European (blue.) On each chromosome where we find a minority segment, the opposite chromosome in the same location is European, meaning blue.

Let’s look at another example.

At FamilyTreeDNA, the person whose ethnicity painting is shown below has a Native American (pink) ancestor on their father’s side. FamilyTreeDNA has correctly phased or identified their Native segments as all belonging to the second chromosome in each pair.

Looking at chromosome 18, for example, most of their father’s chromosome is Native American (pink). The other parent’s chromosome is European (dark blue) at those same locations.

If one of the parents was of one ethnicity, and the other parent is a completely different ethnicity, then one bar of each chromosome would be all pink, for example, and one would be entirely blue, representing the other ethnicity.

Phasing ethnicity or populations to maternal and paternal sides is not foolproof, and each chromosome is phased individually.

Ethnicity can, in some cases, give you a really good idea of what you’re dealing with in terms of heritage and endogamy.

If someone had an Ashkenazi Jewish father and European mother, for example, one copy of each chromosome would be yellow (Ashkenazi Jewish), and one would be blue (European.)

However, if each of their parents were half European Jewish and half European (not Jewish), then their different colored segments would be scattered across their entire set of chromosomes.

In this case, both of the tester’s parents are mixed – European Jewish (green) and Western Europe (blue.) We know both parents are admixed from the same two populations because in some locations, both parents contributed blue (Western Europe), and in other locations, both contributed Jewish (green) segments.

Both MyHeritage and Ancestry provide a secondary tool that’s connected to ethnicity, but different and generally in more recent times.

Ancestry’s DNA Communities

While your ethnicity may not point to anything terribly exciting in terms of endogamy, Genetic Communities might. Ancestry says that a DNA Community is a group of people who share DNA because their relatives recently lived in the same place at the same time, and that communities are much smaller than ethnicity regions and reach back only about 50-300 years.

Based on the ancestors’ locations in the trees of me and my matches, Ancestry has determined that I’m connected to two communities. In my case, the blue group is clearly my father’s line. The orange group could be either parent, or even a combination of both.

My endogamous Brethren could be showing up in Maryland, Pennsylvania, and Ohio, but it’s uncertain, in part, because my father’s ancestral lines are found in Virginia, West Virginia, and Maryland too.

These aren’t useful for me, but they may be more useful for fully endogamous people, especially in conjunction with ethnicity.

My Acadian cousin’s European ethnicity isn’t informative.

However, viewing his DNA Communities puts his French heritage into perspective, especially combined with his match surnames.

I wrote about DNA Communities when it was introduced with the name Genetic Communities, here.

MyHeritage’s Genetic Groups

MyHeritage also provides a similar feature that shows where my matches’ ancestors lived in the same locations as mine.

One difference, though, is that testers can adjust their ethnicity results confidence level from high, above, to low, below where one of my Genetic Groups overlaps my ethnicity in the Netherlands.

You can also sort your matches by Genetic Groups.

The results show you not only who is in the group, but how many of your matches are in that group too, which provides perspective.

I wrote about Genetic Groups, here.

Next, let’s look at how endogamy affects your matches.

Matches

The number of matches that a person has who is from an entirely endogamous community and a person with no endogamy may be quite different.

FamilyTreeDNA provides a Family Matching feature that triangulates your matches and assigns them to your paternal or maternal side by using known matches that you have linked to their profile cards in your tree. You must link people for the Family Matching feature known as “bucketing” to be enabled.

The people you link are then processed for shared matches on the same chromosome segment(s). Triangulated individuals are then deposited in your maternal, paternal, and both buckets.

Obviously, your two parents are the best people to link, but if they haven’t tested (or uploaded their DNA file from another vendor) and you have other known relatives, link them using the Family Tree tab at the top of your personal page.

I uploaded my Ancestry V4 kit to use as an example for linking. Let’s pretend that’s my sister. If I had not already linked my Ancestry V4 kit to “my sister’s” profile card, I’d want to do that and link other known individuals the same way. Just drag and drop the match to the correct profile card.

Note that a full or half sibling will be listed as such at FamilyTreeDNA, but an identical twin will show as a potential parent/child match to you. You’re much more likely to find a parent than an identical twin, but just be aware.

I’ve created a table of FamilyTreeDNA bucketed match results, by category, comparing the number of matches in endogamous categories with non-endogamous.

Total Matches Maternal Matches Paternal Matches Both % Both % DNA Unassigned
100% Jewish 34,637 11,329 10,416 4,806 13.9 23.3
100% Jewish 32,973 10,700 9,858 4,606 14 23.7
100% Jewish 32,255 9,060 10,970 3,892 12 25.8
75% Jewish 24,232 11,846 Only mother linked Only mother linked Only mother linked
100% Acadian 8093 3826 2299 1062 13 11
100% Acadian 7828 3763 1825 923 11.8 17
Not Endogamous 6760 3845 1909 13 0.19 14.5
Not Endogamous 7723 1470 3317 6 0.08 38
100% Native American 1,115 Unlinked Unlinked Unlinked
100% Native American 885 290 Unknown Can’t calculate without at least one link on both sides

The 100% Jewish, Acadian, and Not Endogamous testers both have linked their parents, so their matches, if valid (meaning not identical by chance, which I discussed here,) will match them plus one or the other parent.

One person is 75% Jewish and has only linked their Jewish mother.

The Native people have not tested their parents, and the first Native person has not linked anyone in their tree. The second Native person has only linked a few maternal matches, but their mother has not tested. They are seeking their father.

It’s very difficult to find people who are fully Native as testers. Furthermore, Native people are under-sampled. If anyone knows of fully Native (or other endogamous) people who have tested and linked their parents or known relatives in their trees, and will allow me to use their total match numbers anonymously, please let me know.

As you can see, Jewish, Acadian, and Native people are 100% endogamous, but many more Jewish people than Native people have tested, so you CAN’T judge endogamy by the total number of matches alone.

In fact, in order:

  • Fully Jewish testers have about 4-5 times as many matches as the Acadian and Non-endogamous testers
  • Acadian and Non-endogamous testers have about 5-6 times as many matches as the Native American testers
  • Fully Jewish people have about 30 times more matches than the Native American testers

If a person’s endogamy with a particular population is only on their maternal or paternal side, they won’t have a significant number of people related to both sides, meaning few people will fall into the “Both” bucket. People that will always be found in the ”Both” bucket are full siblings and their descendants, along with descendants of the tester, assuming their match is linked to their profiles in the tester’s tree.

In the case of our Jewish testers, you can easily see that the “Both” bucket is very high. The Acadians are also higher than one would reasonably expect without endogamy. A non-endogamous person might have a few matches on both sides, assuming the parents are not related to each other.

A high number of “Both” matches is a very good indicator of endogamy within the same population on both parents’ sides.

The percentage of people who are assigned to the “Both” bucket is between 11% and 14% in the endogamous groups, and less than 1% in the non-endogamous group, so statistically not relevant.

As demonstrated by the Native people compared to the Jewish testers, the total number of matches can be deceiving.

However, being related to both parents, as indicated by the “Both” bucket, unless you have pedigree collapse, is a good indicator of endogamy.

Of course, if you don’t know who your relatives are, you can’t link them in your tree, so this type of “hunt” won’t generally help people seeking their close family members.

However, you may notice that you’re matching people PLUS both of their parents. If that’s the case, start asking questions of those matches about their heritage.

A very high number of total matches, as compared to non-endogamous people, combined with some other hints might well point to Jewish heritage.

I included the % DNA Unassigned category because this category, when both parents are linked, is the percentage of matches by chance, meaning the match doesn’t match either of the tester’s parents. All of the people with people listed in “Both” categories have linked both of their parents, not just maternal and paternal relatives.

Matching Location at MyHeritage

MyHeritage provides a matching function by location. Please note that it’s the location of the tester, but that may still be quite useful.

The locations are shown in the most-matches to least-matches order. Clicking on the location shows the people who match you who are from that location. This would be the most useful in situations where recent immigration has occurred. In my case, my great-grandfather from the Netherlands arrived in the 1860s, and my German ancestors arrived in the 1850s. Neither of those groups are endogamous, though, unless it would be on a village level.

AutoClusters

Let’s shift to Genetic Affairs, a third-party tool available to everyone.

Using their AutoCluster function, Genetic Affairs clusters your matches together who match both each other and you.

This is an example of the first few clusters in my AutoCluster. You can see that I have several colored clusters of various sizes, but none are huge.

Compare that to the following endogamous cluster, sample courtesy of EJ Blom at Genetic Affairs.

If your AutoCluster at Genetic Affairs looks something like this, a huge orange blob in the upper left hand corner, you’re dealing with endogamy.

Please also note that the size of your cluster is also a function of both the number of testers and the match threshold you select. I always begin by using the defaults. I wrote about using Genetic Affairs, here.

If you tested at or transferred to MyHeritage, they too license AutoClusters, but have optimized the algorithm to tease out endogamous matches so that their Jewish customers, in particular, don’t wind up with a huge orange block of interrelated people.

You won’t see the “endogamy signature” huge cluster in the corner, so you’re less likely to be able to discern endogamy from a MyHeritage cluster alone.

The commonality between these Jewish clusters at MyHeritage is that they all tend to be rather uniform in size and small, with lots of grey connecting almost all the blocks.

Grey cells indicate people who match people in two colored groups. In other words, there is often no clear division in clusters between the mother’s side and the father’s side in Jewish clusters.

In non-endogamous situations, even if you can’t identify the parents, the clusters should still fall into two sides, meaning a group of clusters for each parent’s side that are not related to each other.

You can read more about Genetic Affairs clusters and their tools, here. DNAGedcom.com also provides a clustering tool.

Endogamous Relationships

Endogamous estimated relationships are sometimes high. Please note the word, “sometimes.”

Using the Shared cM Project tool relationship chart, here, at DNAPainter, people with heavy endogamy will discover that estimated relationships MAY be on the high side, or the relationships may, perhaps, be estimated too “close” in time. That’s especially true for more distant relationships, but surprisingly, it’s not always true. The randomness of inheritance still comes into play, and so do potential unknown relatives. Hence, the words “may” are bolded and underscored.

Unfortunately, it’s often stated as “conventional wisdom” that Jewish matches are “always” high, and first cousins appear as siblings. Let’s see what the actual data says.

At DNAPainter, you can either enter the amount of shared DNA (cM), or the percent of shared DNA, or just use the chart provided.

I’ve assembled a compilation of close relationships in kits that I have access to or from people who were generous enough to share their results for this article.

I’ve used Jewish results, which is a highly endogamous population, compared with non-endogamous testers.

The “Jewish Actual” column reports the total amount of shared DNA with that person. In other words, someone to their grandparent. The Average Range is the average plus the range from DNAPainter. The Percent Difference is the % difference between the actual number and the DNAPainter average.

You’ll see fully Jewish testers, at left, matching with their family members, and a Non-endogamous person, at right, matching with their same relative.

Relationship Jewish Actual Percent Difference than Average Average -Range Non-endogamous Actual Percent Difference than Average
Grandparent 2141 22 1754 (984-2482) 1742 <1 lower
Grandparent 1902 8.5 1754 (984-2482) 1973 12
Sibling 3039 16 2613 (1613-3488) 2515 3.5 lower
Sibling 2724 4 2613 (1613-3488) 2761 5.5
Half-Sibling 2184 24 1759 (1160-2436) 2127 21
Half-Sibling 2128 21 1759 (1160-2436) 2352 34
Aunt/Uncle 2066 18.5 1741 (1201-2282) 1849 6
Aunt/Uncle 2031 16.5 1741 (1201-2282) 2097 20
1C 1119 29 866 (396-1397) 959 11
1C 909 5 866 (396-1397) 789 9 lower
1C1R 514 19 433 (102-980) 467 8
1C1R 459 6 433 (102-980) 395 9 lower

These totals are from FamilyTreeDNA except one from GEDMatch (one Jewish Half-sibling).

Totals may vary by vendor, even when matching with the same person. 23andMe includes the X segments in the total cMs and also counts fully identical segments twice. MyHeritage imputation seems to err on the generous side.

However, in these dozen examples:

  • You can see that the Jewish actual amount of DNA shared is always more than the average in the estimate.
  • The red means the overage is more than 100 cM larger.
  • The percentage difference is probably more meaningful because 100 cM is a smaller percentage of a 1754 grandparent connection than compared to a 433 cM 1C1R.

However, you can’t tell anything about endogamy by just looking at any one sample, because:

  • Some of the Non-Endogamous matches are high too. That’s just the way of random inheritance.
  • All of the actual Jewish match numbers are within the published ranges, but on the high side.

Furthermore, it can get more complex.

Half Endogamous

I requested assistance from Jewish genealogy researchers, and a lovely lady, Sharon, reached out, compiled her segment information, and shared it with me, granting permission to share with you. A HUGE thank you to Sharon!

Sharon is half-Jewish via one parent, and her half-sibling is fully Jewish. Their half-sibling match to each other at Ancestry is 1756 cM with a longest segment of 164 cM.

How does Jewish matching vary if you’re half-Jewish versus fully Jewish? Let’s look at 21 people who match both Sharon and her fully Jewish half-sibling.

Sharon shared the differences in 21 known Jewish matches with her and her half-sibling. I’ve added the Relationship Estimate Range from DNAPainter and colorized the highest of the two matches in yellow. Bolding in the total cM column shows a value above the average range for that relationship.

Total Matching cMs is on the left, with Longest Segment on the right.

While this is clearly not a scientific study, it is a representative sample.

The fully Jewish sibling carries more Jewish DNA, which is available for other Jewish matches to match as a function of endogamy (identical by chance/population), so I would have expected the fully Jewish sibling to match most if not all Jewish testers at a higher level than the half-Jewish sibling.

However, that’s not universally what we see.

The fully Jewish sibling is not always the sibling with the highest number of matches to the other Jewish testers, although the half-Jewish tester has the larger “Longest Segment” more often than not.

Approximately two-thirds of the time (13/21), the fully Jewish person does have a higher total matching cM, but about one-third of the time (8/21), the half-Jewish sibling has a higher matching cM.

About one-fourth of the time (5/21), the fully Jewish sibling has the longest matching segment, and about two-thirds of the time (13/21), the half-Jewish sibling does. In three cases, or about 14% of the time, the longest segment is equal which may indicate that it’s the same segment.

Because of endogamy, Jewish matches are more likely to have:

  • Larger than average total cM for the specific relationship
  • More and smaller matching segments

However, as we have seen, neither of those are definitive, nor always true. Jewish matches and relationships are not always overestimated.

Ancestry and Timber

Please note that Ancestry downweights some matches by removing some segments using their Timber algorithm. Based on my matches and other accounts that I manage, Ancestry does not downweight in the 2-3rd cousin category, which is 90 cM and above, but they do begin downweighting in the 3-4th cousin category, below 90 cM, where my “Extended Family” category begins.

If you’ve tested at Ancestry, you can check for yourself.

By clicking on the amount of DNA you share with your match on your match list at Ancestry, shown above, you will be taken to another page where you will be able to view the unweighted shared DNA with that match, meaning the amount of DNA shared before the downweighting and removal of some segments, shown below.

Given the downweighting, and the information in the spreadsheet provided by Sharon, it doesn’t appear that any of those matches would have been in a category to be downweighted.

Therefore, for these and other close matches, Timber wouldn’t be a factor, but would potentially be in more distant matches.

Endogamous Segments

Endogamous matches tend to have smaller and more segments. Small amounts of matching DNA tend to skew the total DNA cM upwards.

How and why does this happen?

Ancestral DNA from further back in time tends to be broken into smaller segments.

Sometimes, especially in endogamous situations, two smaller segments, at one time separated from each other, manage to join back together again and form a match, but the match is only due to ancestral segments – not because of a recent ancestor.

Please note that different vendors have different minimum matching cM thresholds, so smaller matches may not be available at all vendors. Remember that factors like Timber and imputation can affect matching as well.

Let’s take a look at an example. I’ve created a chart where two ancestors have their blue and pink DNA broken into 4 cM segments.

They have children, a blue child and a pink child, and the two children, shown above, each inherited the same blue 4 cM segment and the same pink 4 cM segment from their respective parents. The other unlabeled pink and blue segments are not inherited by these two children, so those unlabeled segments are irrelevant in this example.

The parents may have had other children who inherited those same 4 cM labeled pink and blue segments as well, and if not, the parents’ siblings were probably passing at least some of the same DNA down to their descendants too.

The blue and pink children had children, and their children had children – for several generations.

Time passed, and their descendants became an endogamous community. Those pink and blue 4 cM segments may at some time be lost during recombination in the descendants of each of their children, shown by “Lost pink” and “Lost blue.”

However, because there is only a very limited amount of DNA within the endogamous community, their descendants may regain those same segments again from their “other parent” during recombination, downstream.

In each generation, the DNA of the descendant carrying the original blue or pink DNA segment is recombined with their partner. Given that the partners are both members of the same endogamous community, the two people may have the same pink and/or blue DNA segments. If one parent doesn’t carry the pink 4 cM segment, for example, their offspring may receive that ancestral pink segment from the other parent.

They could potentially, and sometimes do, receive that ancestral segment from both parents.

In our example, the descendants of the blue child, at left, lost the pink 4 cM segment in generation 3, but a few generations later, in generation 11, that descendant child inherited that same pink 4 cM segment from their other parent. Therefore, both the 4 cM blue and 4 cM pink segments are now available to be inherited by the descendants in that line. I’ve shown the opposite scenario in the generational inheritance at right where the blue segment is lost and regained.

Once rejoined, that pink and blue segment can be passed along together for generations.

The important part, though, is that once those two segments butt up against each other again during recombination, they aren’t just two separate 4 cM segments, but one segment that is 8 cM long – that is now equal to or above the vendors’ matching threshold.

This is why people descended from endogamous populations often have the following matching characteristics:

  • More matches
  • Many smaller segment matches
  • Their total cM is often broken into more, smaller segments

What does more, smaller segments, look like, exactly?

More, Smaller Segments

All of our vendors except Ancestry have a chromosome browser for their customers to compare their DNA to that of their matches visually.

Let’s take a look at some examples of what endogamous and non-endogamous matches look like.

For example, here’s a screen shot of a random Jewish second cousin match – 298 cM total, divided into 12 segments, with a longest segment of 58 cM,

A second Jewish 2C with 323 cM total, across 19 segments, with a 69 cM longest block.

A fully Acadian 2C match with 600 cM total, across 27 segments, with a longest segment of 69 cM.

A second Acadian 2C with 332 cM total, across 20 segments, with a longest segment of 42 cM.

Next, a non-endogamous 2C match with 217 cM, across 7 segments, with a longest segment of 72 cM.

Here’s another non-endogamous 2C example, with 169 shared cM, across 6 segments, with a longest segment of 70 cM.

Here’s the second cousin data in a summary table. The take-away from this is the proportion of total segments

Tester Population Total cM Longest Block Total Segments
Jewish 2C 298 58 12
Jewish 2C 323 69 19
Acadian 2C 600 69 27
Acadian 2C 332 42 20
Non-endogamous 2C 217 72 7
Non-endogamous 2C 169 70 6

You can see more examples and comparisons between Native American, Jewish and non-endogamous DNA individuals in the article, Concepts – Endogamy and DNA Segments.

I suspect that a savvy mathematician could predict endogamy based on longest block and total segment information.

Lara Diamond, a mathematician, who writes at Lara’s Jewnealogy might be up for this challenge. She just published compiled matching and segment information in her Ashkenazic Shared DNA Survey Results for those who are interested. You can also contribute to Laura’s data, here.

Endogamy, Segments, and Distant Relationships

While not relevant to searching for close relatives, heavily endogamous matches 3C and more distant, to quote one of my Jewish friends, “dissolve into a quagmire of endogamy and are exceedingly difficult to unravel.”

In my own Acadian endogamous line, I often simply have to label them “Acadian” because the DNA tracks back to so many ancestors in different lines. In other words, I can’t tell which ancestor the match is actually pointing to because the same DNA segments or segments is/are carried by several ancestors and their descendants due to founder effect.

The difference with the Acadians is that we can actually identify many or most of them, at least at some point in time. As my cousin, Paul LeBlanc, once said, if you’re related to one Acadian, you’re related to all Acadians. Then he proceeded to tell me that he and I are related 137 different ways. My head hurts!

It’s no wonder that endogamy is incredibly difficult beyond the first few generations when it turns into something like multi-colored jello soup.

“Are Your Parents Related?” Tool

There’s another tool that you can utilize to determine if your parents are related to each other.

To determine if your parents are related to each other, you need to know about ROH, or Runs of Homozygosity (ROH).

ROH means that the DNA on both strands or copies of the same chromosome is identical.

For a few locations in a row, ROH can easily happen just by chance, but the longer the segment, the less likely that commonality occurs simply by chance.

The good news is that you don’t need to know the identity of either of your parents. You don’t need either of your parent’s DNA tests – just your own. You’ll need to upload your DNA file to GEDmatch, which is free.

Click on “Are your parents related?”

GEDMatch analyzes your DNA to see if any of your DNA, above a reasonable matching threshold, is identical on both strands, indicating that you inherited the exact same DNA from both of your parents.

A legitimate match, meaning one that’s not by chance, will include many contiguous matching locations, generally a minimum of 500 SNPs or locations in a row. GEDmatch’s minimum threshold for identifying identical ancestral DNA (ROH) is 200 cM.

Here’s my result, including the graphic for the first two chromosomes. Notice the tiny green bars that show identical by chance tiny sliver segments.

I have no significant identical DNA, meaning my parents are not related to each other.

Next, let’s look at an endogamous example where there are small, completely identical segments across a person’s chromosome

This person’s Acadian parents are related to each other, but distantly.

Next, let’s look at a Jewish person’s results.

You’ll notice larger green matching ROH, but not over 200 contiguous SNPs and 7 cM.

GEDMatch reports that this Jewish person’s parents are probably not related within recent generations, but it’s clear that they do share DNA in common.

People whose parents are distantly related have relatively small, scattered matching segments. However, if you’re seeing larger ROH segments that would be large enough to match in a genealogical setting, meaning multiple greater than 7 cM and 500 SNPs,, you may be dealing with a different type of situation where cousins have married in recent generations. The larger the matching segments, generally, the closer in time.

Blogger Kitty Cooper wrote an article, here, about discovering that your parents are related at the first cousin level, and what their GEDMatch “Are Your Parents Related” results look like.

Let’s look for more clues.

Surnames

There MAY be an endogamy clue in the surnames of the people you match.

Viewing surnames is easier if you download your match list, which you can do at every vendor except Ancestry. I’m not referring to the segment data, but the information about your matches themselves.

I provided instructions in the recent article, How to Download Your DNA Match Lists and Segment Files, here.

If you suspect endogamy for any reason, look at your closest matches and see if there is a discernable trend in the surnames, or locations, or any commonality between your matches to each other.

For example, Jewish, Acadian, and Native surnames may be recognizable, as may locations.

You can evaluate in either or both of two ways:

  • The surnames of your closest matches. Closest matches listed first will be your default match order.
  • Your most frequently occurring surnames, minus extremely common names like Smith, Jones, etc., unless they are also in your closest matches. To utilize this type of matching, sort the spreadsheet in surname order and then scan or count the number of people with each surname.

Here are some examples from our testers.

Jewish – Closest surname matches.

  • Roth
  • Weiss
  • Goldman
  • Schonwald
  • Levi
  • Cohen
  • Slavin
  • Goodman
  • Sender
  • Trebatch

Acadian – Closest surname matches.

  • Bergeron
  • Hebert
  • Bergeron
  • Marcum
  • Muise
  • Legere
  • Gaudet
  • Perry
  • Verlander
  • Trombley

Native American – Closest surname matches.

  • Ortega
  • Begay
  • Valentine
  • Hayes
  • Montoya
  • Sun Bear
  • Martin
  • Tsosie
  • Chiquito
  • Yazzie

You may recognize these categories of surnames immediately.

If not, Google is your friend. Eliminate common surnames, then Google for a few together at a time and see what emerges.

The most unusual surnames are likely your best bets.

Projects

Another way to get some idea of what groups people with these surnames might belong to is to enter the surname in the FamilyTreeDNA surname search.

Go to the main FamilyTreeDNA page, but DO NOT sign on.

Scroll down until you see this image.

Type the surname into the search box. You’ll see how many people have tested with that surname, along with projects where project administrators have included that surname indicating that the project may be of interest to at least some people with that surname.

Here’s a portion of the project list for Cohen, a traditional Jewish surname.

These results are for Muise, an Acadian surname.

Clicking through to relevant surname projects, and potentially contacting the volunteer project administrator can go a very long way in helping you gather and sift information. Clearly, they have an interest in this topic.

For example, here’s the Muise surname in the Acadian AmerIndian project. Two great hints here – Acadian heritage and Halifax, Nova Scotia.

Repeat for the balance of surnames on your list to look for commonalities, including locations on the public project pages.

Locations

Some of the vendor match files include location information. Each person on your match list will have the opportunity at the vendor where they tested to include location information in a variety of ways, either for their ancestors or themselves.

Where possible, it’s easiest to sort or scan the download file for this type of information.

Ancestry does not provide or facilitate a match list, but you can still create your own for your closest 20 or 30 matches in a spreadsheet.

MyHeritage provides common surname and ancestral location information for every match. How cool is that!

Y DNA, Mitochondrial DNA, and Endogamy

Haplogroups for both Y and mitochondrial DNA can indicate and sometimes confirm endogamy. In other cases, the haplogroup won’t help, but the matches and their location information just might.

FamilyTreeDNA is the only vendor that provides Y DNA and mitochondrial DNA tests that include highly granular haplogroups along with matches and additional tools.

23andMe provides high-level haplogroups which may or may not be adequate to pinpoint a haplogroup that indicates endogamy.

Of course, only males carry Y DNA that tracks to the direct paternal (surname) line, but everyone carries their mother’s mitochondrial DNA that represents their mother’s mother’s mother’s, or direct matrilineal line.

Some haplogroups are known to be closely associated with particular ethnicities or populations, like Native Americans, Pacific Islanders, and some Jewish people.

Haplogroups reach back in time before genealogy and can give us a sense of community that’s not available by either looking in the mirror or through traditional records.

This Native American man is a member of high-level haplogroup Q-M242. However, some men who carry this haplogroup are not Native, but are of European or Middle Eastern origin.

I entered the haplogroup in the FamilyTreeDNA Discover tool, which I wrote about, here.

Checking the information about this haplogroup reveals that their common ancestor descended from an Asian man about 30,000 years ago.

The migration path in the Americans explains why this person would have an endogamous heritage.

Our tester would receive a much more refined haplogroup if he upgraded to the Big Y test at FamilyTreeDNA, which would remove all doubt.

However, even without additional testing, information about his matches at FamilyTreeDNA may be very illuminating.

The Q-M242 Native man’s Y DNA matches men with more granular haplogroups, shown above, at left. On the Haplogroup Origins report, you can see that these people have all selected the “US (Native American)” country option.

Another useful tool would be to check the public Y haplotree, here, and the public mitochondrial tree here, for self-reported ancestor location information for a specific haplogroup.

Here’s an example of mitochondrial haplogroup A2 and a few subclades on the public mitochondrial tree. You can see that the haplogroup is found in Mexico, the US (Native,) Canada, and many additional Caribbean, South, and Central American countries.

Of course, Y DNA and mitochondrial DNA (mtDNA) tell a laser-focused story of one specific line, each. The great news, if you’re seeking information about your mother or father, the Y is your father’s direct paternal (surname) line, and mitochondrial is your mother’s direct matrilineal line.

Y and mitochondrial DNA results combined with ethnicity, autosomal matching, and the wide range of other tools that open doors, you will be able to reveal a great deal of information about whether you have endogamous heritage or not – and if so, from where.

I’ve provided a resource for stepping through and interpreting your Y DNA results, here, and mitochondrial DNA, here.

Discover for Y DNA Only

If you’re a female, you may feel left out of Y DNA testing and what it can tell you about your heritage. However, there’s a back door.

You can utilize the Y DNA haplogroups of your closest autosomal matches at both FamilyTreeDNA and 23andMe to reveal information

Haplogroup information is available in the download files for both vendors, in addition to the Family Finder table view, below, at FamilyTreeDNA, or on your individual matches profile cards at both 23andMe and FamilyTreeDNA.

You can enter any Y DNA haplogroup in the FamilyTreeDNA Discover tool, here.

You’ll be treated to:

  • Your Haplogroup Story – how many testers have this haplogroup (so far), where the haplogroup is from, and the haplogroup’s age. In this case, the haplogroup was born in the Netherlands about 250 years ago, give or take 200 years. I know that it was 1806 or earlier based on the common ancestor of the men who tested.
  • Country Frequency – heat map of where the haplogroup is found in the world.
  • Notable Connections – famous and infamous (this haplogroup’s closest notable person is Leo Tolstoy).
  • Migration Map – migration path out of Africa and through the rest of the world.
  • Ancient Connections – ancient burials. His closest ancient match is from about 1000 years ago in Ukraine. Their shared ancestor lived about 2000 years ago.
  • Suggested Projects – based on the surname, projects that other matches have joined, and haplogroups.
  • Scientific Details – age estimates, confidence intervals, graphs, and the mutations that define this haplogroup.

I wrote about the Discover tool in the article, FamilyTreeDNA DISCOVER Launches – Including Y DNA Haplogroup Ages.

Endogamy Tools Summary Tables

Endogamy is a tough nut sometimes, especially if you’re starting from scratch. In order to make this topic a bit easier and to create a reference tool for you, I’ve created three summary tables.

  • Various endogamy-related tools available at each vendor which will or may assist with evaluating endogamy
  • Tools and their ability to detect endogamy in different groups
  • Tools best suited to assist people seeking information about unknown parents or grandparents

Summary of Endogamy Tools by Vendor

Please note that GEDMatch is not a DNA testing vendor, but they accept uploads and do have some tools that the testing vendors do not.

 Tool 23andMe Ancestry FamilyTreeDNA MyHeritage GEDMatch
Ethnicity Yes Yes Yes Yes Use the vendors
Ethnicity Painting Yes + segments Yes, limited Yes + segments Yes
Ethnicity Phasing Yes Partial Yes No
DNA Communities No Yes No No
Genetic Groups No No No Yes
Family Matching aka Bucketing No No Yes No
Chromosome Browser Yes No Yes Yes Yes
AutoClusters Through Genetic Affairs No Through Genetic Affairs Yes, included Yes, with subscription
Match List Download Yes, restricted # of matches No Yes Yes Yes
Projects No No Yes No
Y DNA High-level haplogroup only No Yes, full haplogroup with Big Y, matching, tools, Discover No
Mitochondrial DNA High-level haplogroup only No Yes, full haplogroup with mtFull, matching, tools No
Public Y Tree No No Yes No
Public Mito Tree No No Yes No
Discover Y DNA – public No No Yes No
ROH No No No No Yes

Summary of Endogamous Populations Identified by Each Tool

The following chart provides a guideline for which tools are useful for the following types of endogamous groups. Bolded tools require that both parents be descended from the same endogamous group, but several other tools give more definitive results with higher amounts of endogamy.

Y and mitochondrial DNA testing are not affected by admixture, autosomal DNA or anything from the “other” parent.

Tool Jewish Acadian Anabaptist Native Other/General
Ethnicity Yes No No Yes Pacific Islander
Ethnicity Painting Yes No No Yes Pacific Islander
Ethnicity Phasing Yes, if different No No Yes, if different Pacific Islander, if different
DNA Communities Yes Possibly Possibly Yes Pacific Islander
Genetic Groups Yes Possibly Possibly Yes Pacific Islander
Family Matching aka Bucketing Yes Yes Possibly Yes Pacific Islander
Chromosome Browser Possibly Possibly Yes, once segments or ancestors identified Possibly Pacific Islander, possibly
Total Matches Yes, compared to non-endogamous No No No No, unknown
AutoClusters Yes Yes Uncertain, probably Yes Pacific Islander
Estimated Relationships High Not always Sometimes No Sometimes Uncertain, probably
Relationship Range High Possibly, sometimes Possibly Possibly Possibly Pacific Islander, possibly
More, Smaller Segments Yes Yes Probably Yes Pacific Islander, probably
Parents Related Some but minimal Possibly Uncertain Probably similar to Jewish Uncertain, Possibly
Surnames Probably Probably Probably Not Possibly Possibly
Locations Possibly Probably Probably Not Probably Probably Pacific Islander
Projects Probably Probably Possibly Possibly Probably Pacific Islander
Y DNA Yes, often Yes, often No Yes Pacific Islander
Mitochondrial DNA Yes, often Sometimes No Yes Pacific Islander
Y public tree Probably not alone No No Yes Pacific Islander
MtDNA public tree Probably not No No Yes Pacific Islander
Y DNA Discover Yes Possibly Probably not, maybe projects Yes Pacific Islander

Summary of Endogamy Tools to Assist People Seeking Unknown Parents and Grandparents

This table provides a summary of when each of the various tools can be useful to:

  • People seeking unknown close relatives
  • People who already know who their close relatives are, but are seeking additional information or clues about their genealogy

I considered rating these on a 1 to 10 scale, but the relative usefulness of these tools is dependent on many factors, so different tools will be more or less useful to different people.

For example, ethnicity is very useful if someone is admixed from different populations, or even 100% of a specific endogamous population. It’s less useful if the tester is 100% European, regardless of whether they are seeking close relatives or not. Conversely, even “vanilla” ethnicity can be used to rule out majority or recent admixture with many populations.

Tools Unknown Close Relative Seekers Known Close Relatives – Enhance Genealogy
Ethnicity Yes, to identify or rule out populations Yes
Ethnicity Painting Yes, possibly, depending on population Yes, possibly, depending on population
Ethnicity Phasing Yes, possibly, depending on population Yes, possibly, depending on population
DNA Communities Yes, possibly, depending on population Yes, possibly, depending on population
Genetic Groups Possibly, depending on population Possibly, depending on population
Family Matching aka Bucketing Not if parents are entirely unknown, but yes if one parent is known Yes
Chromosome Browser Unlikely Yes
AutoClusters Yes Yes, especially at MyHeritage if Jewish
Estimated Relationships High Not No
Relationship Range High Not reliably No
More, Smaller Segments Unlikely Unlikely other than confirmation
Match List Download Yes Yes
Surnames Yes Yes
Locations Yes Yes
Projects Yes Yes
Y DNA Yes, males only, direct paternal line, identifies surname lineage Yes, males only, direct paternal line, identifies and correctly places surname lineage
Mitochondrial DNA Yes, both sexes, direct matrilineal line only Yes, both sexes, direct matrilineal line only
Public Y Tree Yes for locations Yes for locations
Public Mito Tree Yes for locations Yes for locations
Discover Y DNA Yes, for heritage information Yes, for heritage information
Parents Related – ROH Possibly Less useful

Acknowledgments

A HUGE thank you to several people who contributed images and information in order to provide accurate and expanded information on the topic of endogamy. Many did not want to be mentioned by name, but you know who you are!!!

If you have information to add, please post in the comments.

_____________________________________________________________

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East Coast Genetic Genealogy Conference – Registration is Open!

Did you know that the East Coast Genetic Genealogy Conference (ECGGC, affectionally known as “eggs”) is taking place on April 23 and 24? If you haven’t heard of this conference before, that’s because this is its inaugural year.

ECCGC was initially scheduled to be held in Maryland, in person, but the uptick in Covid over the winter forced a go, no-go decision at a time when a virtual live-streamed conference assured everyone’s safety.

I’m excited about speaking, especially my opening keynote, “DNA – Past, Present and Future.” I’ll reflect a little, talk about the current state-of-affairs and then discuss what the future may hold. Just think what we will be able to do in the next decade, or two, based on how far we’ve come in the past 22 years.

Of course, the very best aspect of this two-day conference is that it’s entirely focused on genetic genealogy which makes it the PERFECT venue for Mitochondrial DNA Academy. More about that in a minute.

Speakers

The 23 speakers read like a who’s who in the genetic genealogy space. You can read about each speaker, here.

Schedule and Sessions

If you look at the sessions and schedule, here, you’ll notice that there are 37 sessions offered over two days. Simple math tells you that you can’t possibly attend all of those in two days – even if you stayed up all night.

The great news is that for all attendees, the sessions will be recorded and available to watch after the actual conference itself is over.

Mitochondrial DNA Academy – You’re Invited

I want to personally invite you to attend Mitochondrial DNA Academy, presented by Dr. Miguel Vilar, Dr. Paul Maier, and me.

Mitochondrial DNA is an incredibly misunderstood tool for genealogy. It seems that anytime someone mentions mitochondrial DNA on social media and asks if they should purchase a test, a cacophony of “buy an autosomal test instead” resounds, without even asking the purpose of the test in question, or what the person hopes to learn.

Understanding mitochondrial DNA itself, how it’s used, what to expect, and how to utilize the results for genealogy is key to making an informed decision.

For those of us who do work extensively with mitochondrial DNA, there’s still much to learn. Attending both Paul Maier and Miguel Vilar’s portions of the Academy is guaranteed to provide even experienced genetic genealogists with fascinating, detailed information. There’s something for everyone and a unique learning opportunity.

If you want to understand the science behind mitochondrial DNA, how it works, different types of mutations, extra and missing mutations, frequency, haplogroup formation, migration, populations, phylogenetic trees as well as how to tie all of this up in a bundle to use successfully for genetic genealogy – Mitochondrial DNA Academy is for you.

You may have noticed that the three of us constitute three-quarters of the Million Mito Project team, so you just might get an update on that project as well!

Register for the Conference

You can register, here, for $150 which provides access to both conference days and all of the recorded sessions after.

Sponsors

I want to say a big thank you to the ECGGC sponsors, DNAGedcom, Borland Genetics, MyHeritage, FamilyTreeDNA and mitoYDNA.org whose generous sponsorships offset the cost of the conference for attendees.

See you at the conference!

_____________________________________________________________

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Share the Love!

You’re always welcome to forward articles or links to friends and share on social media.

If you haven’t already subscribed (it’s free,) you can receive an email whenever I publish by clicking the “follow” button on the main blog page, here.

You Can Help Keep This Blog Free

I receive a small contribution when you click on some of the links to vendors in my articles. This does NOT increase the price you pay but helps me to keep the lights on and this informational blog free for everyone. Please click on the links in the articles or to the vendors below if you are purchasing products or DNA testing.

Thank you so much.

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Genealogy Research

Top Ten RootsTech 2022 DNA Sessions + All DNA Session Links

The official dates of RootsTech 2022 were March 3-5, but the sessions and content in the vendor booths are still available. I’ve compiled a list of the sessions focused on DNA, with web links on the RootsTech YouTube channel

YouTube reports the number of views, so I was able to compile that information as of March 8, 2022.

I do want to explain a couple of things to add context to the numbers.

Most speakers recorded their sessions, but a few offered live sessions which were recorded, then posted later for participants to view. However, there have been glitches in that process. While the sessions were anticipated to be available an hour or so later, that didn’t quite happen, and a couple still aren’t posted. I’m sure the presenters are distressed by this, so be sure to watch those when they are up and running.

The Zoom rooms where participants gathered for the live sessions were restricted to 500 attendees. The YouTube number of views does not include the number of live viewers, so you’ll need to add an additional number, up to 500.

When you see a number before the session name, whether recorded or live, that means that the session is part of a series. RootsTech required speakers to divide longer sessions into a series of shorter sessions no longer than 15-20 minutes each. The goal was for viewers to be able to watch the sessions one after the other, as one class, or separately, and still make sense of the content. Let’s just say this was the most challenging thing I’ve ever done as a presenter.

For recorded series sessions, these are posted as 1, 2 and 3, as you can see below with Diahan Southard’s sessions. However, with my live session series, that didn’t happen. It looks like my sessions are a series, but when you watch them, parts 1, 2 and 3 are recorded and presented as one session. Personally, I’m fine with this, because I think the information makes a lot more sense this way. However, it makes comparisons difficult.

This was only the second year for RootsTech to be virtual and the conference is absolutely HUGE, so live and learn. Next year will be smoother and hopefully, at least partially in-person too.

When I “arrived” to present my live session, “Associating Autosomal DNA Segments With Ancestors,” my lovely moderator, Rhett, told me that they were going to livestream my session to the RootsTech page on Facebook as well because they realized that the 500 Zoom seat limit had been a problem the day before with some popular sessions. I have about 9000 views for that session and more than 7,400 of them are on the RootsTech Facebook page – and that was WITHOUT any advance notice or advertising. I know that the Zoom room was full in addition. I felt kind of strange about including my results in the top ten because I had that advantage, but I didn’t know quite how to otherwise count my session. As it turns out, all sessions with more than 1000 views made it into the top ten so mine would have been there one way or another. A big thank you to everyone who watched!

I hope that the RootsTech team notices that the most viewed session is the one that was NOT constrained by the 500-seat limited AND was live-streamed on Facebook. Seems like this might be a great way to increase session views for everyone next year. Hint, hint!!!

I also want to say a huge thank you to all of the presenters for producing outstanding content. The sessions were challenging to find, plus RootsTech is always hectic, even virtually. So, I know a LOT of people will want to view these informative sessions, now that you know where to look and have more time. Please remember to “like” the session on YouTube as a way of thanking your presenter.

With 140 DNA-focused sessions available, you can watch a new session, and put it to use, every other day for the next year! How fun is that! You can use this article as your own playlist.

Please feel free to share this article with your friends and genealogy groups so everyone can learn more about using DNA for genealogy.

Ok, let’s look at the top 10. Drum roll please…

Top 10 Most Viewed RootsTech Sessions

Session Title Presenter YouTube Link Views
1 1. Associating Autosomal DNA Segments With Ancestors Roberta Estes (live) https://www.youtube.com/watch?v=_IHSCkNnX48

 

~9000: 1019 + 500 live viewers + 7,400+ Facebook
2 1. What to Do with Your DNA Test Results in 2022 (part 1 of 3) Diahan Southard https://www.youtube.com/watch?v=FENAKAYLXX4 7428
3 Who Is FamilyTreeDNA? FamilyTreeDNA – Bennett Greenspan https://www.youtube.com/watch?v=MHFtwoatJ-A 2946
4 2. What to Do with Your DNA Test Results in 2022 (part 2 of 3) Diahan Southard https://www.youtube.com/watch?v=mIllhtONhlI 2448
5 Latest DNA Painter Releases DNAPainter Jonny Perl (live) https://www.youtube.com/watch?v=iLBThU8l33o 2230 + live viewers
6 DNA Painter Introduction DNAPainter – Jonny Perl https://www.youtube.com/watch?v=Rpe5LMPNmf0 1983
7 3. What to Do with Your DNA Test Results in 2022 (part 3 of 3) Diahan Southard https://www.youtube.com/watch?v=hemY5TuLmGI 1780
8 The Tree of Mankind Age Estimates Paul Maier https://www.youtube.com/watch?v=jjkL8PWAEwk 1638
9 A Sneak Peek at FamilyTreeDNA Coming Attractions FamilyTreeDNA (live) https://www.youtube.com/watch?v=K9sKqNScvnE 1270 + live viewers

 

10 Extending Time Horizons with DNA Rob Spencer (live) https://www.youtube.com/watch?v=wppXD1Zz2sQ 1037 + live viewers

 

All DNA-Focused Sessions

I know you’ll find LOTS of goodies here. Which ones are your favorites?

  Session Presenter YouTube Link Views
1 Estimating Relationships by Combining DNA from Multiple Siblings Amy Williams https://www.youtube.com/watch?v=xs1U0ohpKSA 201
2 Overview of HAPI-DNA.org Amy Williams https://www.youtube.com/watch?v=FjNiJgWaBeQ 126
3 How do AncestryDNA® Communities help tell your story? | Ancestry® Ancestry https://www.youtube.com/watch?v=EQNpUxonQO4 183

 

4 AncestryDNA® 201 Ancestry – Crista Cowan https://www.youtube.com/watch?v=lbqpnXloM5s

 

494
5 Genealogy in a Minute: Increase Discoveries by Attaching AncestryDNA® Results to Family Tree Ancestry – Crista Cowan https://www.youtube.com/watch?v=iAqwSCO8Pvw 369
6 AncestryDNA® 101: Beginner’s Guide to AncestryDNA® | Ancestry® Ancestry – Lisa Elzey https://www.youtube.com/watch?v=-N2usCR86sY 909
7 Hidden in Plain Sight: Free People of Color in Your Family Tree Cheri Daniels https://www.youtube.com/watch?v=FUOcdhO3uDM 179
8 Finding Relatives to Prevent Hereditary Cancer ConnectMyVariant – Dr. Brian Shirts https://www.youtube.com/watch?v=LpwLGgEp2IE 63
9 Piling on the chromosomes Debbie Kennett https://www.youtube.com/watch?v=e14lMsS3rcY 465
10 Linking Families With Rare Genetic Condition Using Genealogy Deborah Neklason https://www.youtube.com/watch?v=b94lUfeAw9k 43
11 1. What to Do with Your DNA Test Results in 2022 Diahan Southard https://www.youtube.com/watch?v=FENAKAYLXX4 7428
12 1. What to Do with Your DNA Test Results in 2022 Diahan Southard https://www.youtube.com/watch?v=hemY5TuLmGI 1780
13 2. What to Do with Your DNA Test Results in 2022 Diahan Southard https://www.youtube.com/watch?v=mIllhtONhlI 2448
14 DNA Testing For Family History Diahan Southard https://www.youtube.com/watch?v=kCLuOCC924s 84

 

15 Understanding Your DNA Ethnicity Estimate at 23andMe Diana Elder

 

https://www.youtube.com/watch?v=xT1OtyvbVHE 66
16 Understanding Your Ethnicity Estimate at FamilyTreeDNA Diana Elder https://www.youtube.com/watch?v=XosjViloVE0 73
17 DNA Monkey Wrenches DNA Monkey Wrenches https://www.youtube.com/watch?v=Thv79pmII5M 245
18 Advanced Features in your Ancestral Tree and Fan Chart DNAPainter – Jonny Perl https://www.youtube.com/watch?v=4u5Vf13ZoAc 425
19 DNA Painter Introduction DNAPainter – Jonny Perl https://www.youtube.com/watch?v=Rpe5LMPNmf0 1983
20 Getting Segment Data from 23andMe DNA Matches DNAPainter – Jonny Perl https://www.youtube.com/watch?v=8EBRI85P3KQ 134
21 Getting segment data from FamilyTreeDNA DNA matches DNAPainter – Jonny Perl https://www.youtube.com/watch?v=rWnxK86a12U 169
22 Getting segment data from Gedmatch DNA matches DNAPainter – Jonny Perl https://www.youtube.com/watch?v=WF11HEL8Apk 163
23 Getting segment data from Geneanet DNA Matches DNAPainter – Jonny Perl https://www.youtube.com/watch?v=eclj8Ap0uK4 38
24 Getting segment data from MyHeritage DNA matches DNAPainter – Jonny Perl https://www.youtube.com/watch?v=9rGwOtqbg5E 160
25 Inferred Chromosome Mapping: Maximize your DNA Matches DNAPainter – Jonny Perl https://www.youtube.com/watch?v=tzd5arHkv64 688
26 Keeping track of your genetic family tree in a fan chart DNAPainter – Jonny Perl https://www.youtube.com/watch?v=W3Hcno7en94 806

 

27 Mapping a DNA Match in a Chromosome Map DNAPainter – Jonny Perl https://www.youtube.com/watch?v=A61zQFBWaiY 423
28 Setting up an Ancestral Tree and Fan Chart and Exploring Tree Completeness DNAPainter – Jonny Perl https://www.youtube.com/watch?v=lkJp5Xk1thg 77
29 Using the Shared cM Project Tool to Evaluate DNA Matches DNAPainter – Jonny Perl https://www.youtube.com/watch?v=vxhn9l3Dxg4 763
30 Your First Chromosome Map: Using your DNA Matches to Link Segments to Ancestors DNAPainter – Jonny Perl https://www.youtube.com/watch?v=tzd5arHkv64 688
31 DNA Painter for absolute beginners DNAPainter (Jonny Perl) https://www.youtube.com/watch?v=JwUWW4WHwhk 1196
32 Latest DNA Painter Releases DNAPainter (live) https://www.youtube.com/watch?v=iLBThU8l33o 2230 + live viewers
33 Unraveling your genealogy with DNA segment networks using AutoSegment from Genetic Affairs Evert-Jan Blom https://www.youtube.com/watch?v=rVpsJSqOJZI

 

162
34 Unraveling your genealogy with genetic networks using AutoCluster Evert-Jan Blom https://www.youtube.com/watch?v=ZTKSz_X7_zs 201

 

 

35 Unraveling your genealogy with reconstructed trees using AutoTree & AutoKinship from Genetic Affairs Evert-Jan Blom https://www.youtube.com/watch?v=OmDQoAn9tVw 143
36 Research Like a Pro with DNA – A Genealogist’s Guide to Finding and Confirming Ancestors with DNA Family Locket Genealogists https://www.youtube.com/watch?v=NYpLscJJQyk 183
37 How to Interpret a DNA Network Graph Family Locket Genealogists – Diana Elder https://www.youtube.com/watch?v=i83WRl1uLWY 393
38 Find and Confirm Ancestors with DNA Evidence Family Locket Genealogists – Nicole Dyer https://www.youtube.com/watch?v=DGLpV3aNuZI 144
39 How To Make A DNA Network Graph Family Locket Genealogists – Nicole Dyer https://www.youtube.com/watch?v=MLm_dVK2kAA 201
40 Create A Family Tree With Your DNA Matches-Use Lucidchart To Create A Picture Worth A Thousand Words Family Locket Genealogists – Robin Wirthlin https://www.youtube.com/watch?v=RlRIzcW-JI4 270
41 Charting Companion 7 – DNA Edition Family Tree Maker https://www.youtube.com/watch?v=k2r9rkk22nU 316

 

42 Family Finder Chromosome Browser: How to Use FamilyTreeDNA https://www.youtube.com/watch?v=w0_tgopBn_o 750

 

 

43 FamilyTreeDNA: 22 Years of Breaking Down Brick Walls FamilyTreeDNA https://www.familysearch.org/rootstech/session/familytreedna-22-years-of-breaking-down-brick-walls Not available
44 Review of Autosomal DNA, Y-DNA, & mtDNA FamilyTreeDNA  – Janine Cloud https://www.youtube.com/watch?v=EJoQVKxgaVY 77
45 Who Is FamilyTreeDNA? FamilyTreeDNA – Bennett Greenspan https://www.youtube.com/watch?v=MHFtwoatJ-A 2946
46 Part 1: How to Interpret Y-DNA Results, A Walk Through the Big Y FamilyTreeDNA – Casimir Roman https://www.youtube.com/watch?v=ra1cjGgvhRw 684

 

47 Part 2: How to Interpret Y-DNA Results, A Walk Through the Big Y FamilyTreeDNA – Casimir Roman https://www.youtube.com/watch?v=CgqcjBD6N8Y

 

259
48 Big Y-700: A Brief Overview FamilyTreeDNA – Janine Cloud https://www.youtube.com/watch?v=IefUipZcLCQ 96
49 Mitochondrial DNA & The Million Mito Project FamilyTreeDNA – Janine Cloud https://www.youtube.com/watch?v=5Zppv2uAa6I 179
50 Mitochondrial DNA: What is a Heteroplasmy FamilyTreeDNA – Janine Cloud https://www.youtube.com/watch?v=ZeGTyUDKySk 57
51 Y-DNA Big Y: A Lifetime Analysis FamilyTreeDNA – Janine Cloud https://www.youtube.com/watch?v=E6NEU92rpiM 154
52 Y-DNA: How SNPs Are Added to the Y Haplotree FamilyTreeDNA – Janine Cloud https://www.youtube.com/watch?v=CGQaYcroRwY 220
53 Family Finder myOrigins: Beginner’s Guide FamilyTreeDNA – Katy Rowe https://www.youtube.com/watch?v=VrJNpSv8nlA 88
54 Mitochondrial DNA: Matches Map & Results for mtDNA FamilyTreeDNA – Katy Rowe https://www.youtube.com/watch?v=YtA1j01MOvs 190
55 Mitochondrial DNA: mtDNA Mutations Explained FamilyTreeDNA – Katy Rowe https://www.youtube.com/watch?v=awPs0cmZApE 340

 

56 Y-DNA: Haplotree and SNPs Page Overview FamilyTreeDNA – Katy Rowe https://www.youtube.com/watch?v=FOuVhoMD-hw 432
57 Y-DNA: Understanding the Y-STR Results Page FamilyTreeDNA – Katy Rowe https://www.youtube.com/watch?v=gCeZz1rQplI 148
58 Y-DNA: What Is Genetic Distance? FamilyTreeDNA – Katy Rowe https://www.youtube.com/watch?v=qJ6wY6ILhfg 149
59 DNA Tools: myOrigins 3.0 Explained, Part 1 FamilyTreeDNA – Paul Maier https://www.youtube.com/watch?v=ACgY3F4-w78 74

 

60 DNA Tools: myOrigins 3.0 Explained, Part 2 FamilyTreeDNA – Paul Maier https://www.youtube.com/watch?v=h7qU36bIFg0 50
61 DNA Tools: myOrigins 3.0 Explained, Part 3 FamilyTreeDNA – Paul Maier https://www.youtube.com/watch?v=SWlGPm8BGyU 36
62 African American Genealogy Research Tips FamilyTreeDNA – Sherman McRae https://www.youtube.com/watch?v=XdbkM58rXIQ 153

 

63 Connecting With My Ancestors Through Y-DNA FamilyTreeDNA – Sherman McRae https://www.youtube.com/watch?v=xbo1XnLkuQU 200
64 Join The Million Mito Project FamilyTreeDNA (Join link) https://www.familysearch.org/rootstech/session/join-the-million-mito-project link
65 View the World’s Largest mtDNA Haplotree FamilyTreeDNA (Link to mtDNA tree) https://www.familytreedna.com/public/mt-dna-haplotree/L n/a
66 View the World’s Largest Y Haplotree FamilyTreeDNA (Link to Y tree) https://www.familytreedna.com/public/y-dna-haplotree/A link
67 A Sneak Peek at FamilyTreeDNA Coming Attractions FamilyTreeDNA (live) https://www.youtube.com/watch?v=K9sKqNScvnE 1270 + live viewers

 

68 DNA Upload: How to Transfer Your Autosomal DNA Data FamilyTreeDNA -Katy Rowe https://www.youtube.com/watch?v=CS-rH_HrGlo 303
69 Family Finder myOrigins: How to Compare Origins With Your DNA Matches FamilyTreeDNA -Katy Rowe https://www.youtube.com/watch?v=7mBmWhM4j9Y 145
70 Join Group Projects at FamilyTreeDNA FamilyTreeDNA link to learning center article) https://www.familysearch.org/rootstech/session/join-group-projects-at-familytreedna link

 

71 Product Demo – Unraveling your genealogy with reconstructed trees using AutoKinship GEDmatch https://www.youtube.com/watch?v=R7_W0FM5U7c 803
72 Towards a Genetic Genealogy Driven Irish Reference Genome Gerard Corcoran https://www.youtube.com/watch?v=6Kx8qeNiVmo 155

 

73 Discovering Biological Origins in Chile With DNA: Simple Triangulation Gonzalo Alexis Luengo Orellana https://www.youtube.com/watch?v=WcVby54Uigc 40
74 Cousin Lynne: An Adoption Story International Association of Jewish Genealogical Societies https://www.youtube.com/watch?v=AptMcV4_B4o 111
75 Using DNA Testing to Uncover Native Ancestry Janine Cloud https://www.youtube.com/watch?v=edzebJXepMA 205
76 1. Forensic Genetic Genealogy Jarrett Ross https://www.youtube.com/watch?v=0euIDZTmx5g 58
77 Reunited and it Feels so Good Jennifer Mendelsohn https://www.youtube.com/watch?v=X-hxjm7grBE 57

 

78 Genealogical Research and DNA Testing: The Perfect Companions Kimberly Brown https://www.youtube.com/watch?v=X82jA3xUVXk 80
79 Finding a Jewish Sperm Donor Kitty Munson Cooper https://www.youtube.com/watch?v=iKRjFfNcpug 164
80 Using DNA in South African Genealogy Linda Farrell https://www.youtube.com/watch?v=HXkbBWmORM0 141
81 Using DNA Group Projects In Your Family History Research Mags Gaulden https://www.youtube.com/watch?v=0tX7QDib4Cw 165
82 2. The Expansion of Genealogy Into Forensics Marybeth Sciaretta https://www.youtube.com/watch?v=HcEO-rMe3Xo 35

 

83 DNA Interest Groups That Keep ’em Coming Back McKell Keeney (live) https://www.youtube.com/watch?v=HFwpmtA_QbE 180 plus live viewers
84 Searching for Close Relatives with Your DNA Results Mckell Keeney (live) https://www.familysearch.org/rootstech/session/searching-for-close-relatives-with-your-dna-results Not yet available
85 Top Ten Reasons To DNA Test For Family History Michelle Leonard https://www.youtube.com/watch?v=1B9hEeu_dic 181
86 Top Tips For Identifying DNA Matches Michelle Leonard https://www.youtube.com/watch?v=-3Oay_btNAI 306
87 Maximising Messages Michelle Patient https://www.youtube.com/watch?v=4TRmn0qzHik 442
88 How to Filter and Sort Your DNA Matches MyHeritage https://www.youtube.com/watch?v=fmIgamFDvc8 88
89 How to Get Started with Your DNA Matches MyHeritage https://www.youtube.com/watch?v=JPOzhTxhU0E 447

 

90 How to Track DNA Kits in MyHeritage` MyHeritage https://www.youtube.com/watch?v=2W0zBbkBJ5w 28

 

91 How to Upload Your DNA Data to MyHeritage MyHeritage https://www.youtube.com/watch?v=nJ4RoZOQafY 82
92 How to Use Genetic Groups MyHeritage https://www.youtube.com/watch?v=PtDAUHN-3-4 62
My Story: Hope MyHeritage https://www.youtube.com/watch?v=qjyggKZEXYA 133
93 MyHeritage Keynote, RootsTech 2022 MyHeritage https://www.familysearch.org/rootstech/session/myheritage-keynote-rootstech-2022 Not available
94 Using Labels to Name Your DNA Match List MyHeritage https://www.youtube.com/watch?v=enJjdw1xlsk 139

 

95 An Introduction to DNA on MyHeritage MyHeritage – Daniel Horowitz https://www.youtube.com/watch?v=1I6LHezMkgc 60
96 Using MyHeritage’s Advanced DNA Tools to Shed Light on Your DNA Matches MyHeritage – Daniel Horowitz https://www.youtube.com/watch?v=Pez46Xw20b4 110
97 You’ve Got DNA Matches! Now What? MyHeritage – Daniel Horowitz https://www.youtube.com/watch?v=gl3UVksA-2E 260
98 My Story: Lizzie and Ayla MyHeritage – Elizbeth Shaltz https://www.youtube.com/watch?v=NQv6C8G39Kw 147
99 My Story: Fernando and Iwen MyHeritage – Fernando Hermansson https://www.youtube.com/watch?v=98-AR0M7fFE 165

 

100 Using the Autocluster and the Chromosome Browser to Explore Your DNA Matches MyHeritage – Gal Zruhen https://www.youtube.com/watch?v=a7aQbfP7lWU 115

 

101 My Story : Kara Ashby Utah Wedding MyHeritage – Kara Ashby https://www.youtube.com/watch?v=Qbr_gg1sDRo 200
102 When Harry Met Dotty – using DNA to break down brick walls Nick David Barratt https://www.youtube.com/watch?v=8SdnLuwWpJs 679
103 How to Add a DNA Match to Airtable Nicole Dyer https://www.youtube.com/watch?v=oKxizWIOKC0 161
104 How to Download DNA Match Lists with DNAGedcom Client Nicole Dyer https://www.youtube.com/watch?v=t9zTWnwl98E 124
105 How to Know if a Matching DNA Segment is Maternal or Paternal Nicole Dyer https://www.youtube.com/watch?v=-zd5iat7pmg 161
106 DNA Basics Part I Centimorgans and Family Relationships Origins International, Inc. dba Origins Genealogy https://www.youtube.com/watch?v=SI1yUdnSpHA 372
107 DNA Basics Part II Clustering and Connecting Your DNA Matches Origins International, Inc. dba Origins Genealogy https://www.youtube.com/watch?v=ECs4a1hwGcs 333
108 DNA Basics Part III Charting Your DNA Matches to Get Answers Origins International, Inc. dba Origins Genealogy https://www.youtube.com/watch?v=qzybjN0JBGY 270
109 2. Using Cluster Auto Painter Patricia Coleman https://www.youtube.com/watch?v=-nfLixwxKN4 691
110 3. Using Online Irish Records Patricia Coleman https://www.youtube.com/watch?v=mZsB0l4z4os 802
111 Exploring Different Types of Clusters Patricia Coleman https://www.youtube.com/watch?v=eEZBFPC8aL4 972

 

112 The Million Mito Project: Growing the Family Tree of Womankind Paul Maier https://www.youtube.com/watch?v=cpctoeKb0Kw 541
113 The Tree of Mankind Age Estimates Paul Maier https://www.youtube.com/watch?v=jjkL8PWAEwk 1638
114 Y-DNA and Mitochondrial DNA Testing Plans Paul Woodbury https://www.youtube.com/watch?v=akymSm0QKaY 168
115 Finding Biological Family Price Genealogy https://www.youtube.com/watch?v=4xh-r3hZ6Hw 137
116 What Y-DNA Testing Can Do for You Richard Hill https://www.youtube.com/watch?v=a094YhIY4HU 191
117 Extending Time Horizons with DNA Rob Spencer (live) https://www.youtube.com/watch?v=wppXD1Zz2sQ 1037 + live viewers
118 DNA for Native American Ancestry by Roberta Estes Roberta Estes https://www.youtube.com/watch?v=EbNyXCFfp4M 212
119 1. Associating Autosomal DNA Segments With Ancestors Roberta Estes (live) https://www.youtube.com/watch?v=_IHSCkNnX48

 

~9000: 1019 + 500 live viewers + 7,400+ Facebook
120 1. What Can I Do With Ancestral DNA Segments? Roberta Estes (live) https://www.youtube.com/watch?v=Suv3l4iZYAQ 325 plus live viewers

 

121 Native American DNA – Ancient and Contemporary Maps Roberta Estes (live) https://www.youtube.com/watch?v=dFTl2vXUz_0 212 plus 483 live viewers

 

122 How Can DNA Enhance My Family History Research? Robin Wirthlin https://www.youtube.com/watch?v=f3KKW-U2P6w 102
123 How to Analyze a DNA Match Robin Wirthlin https://www.youtube.com/watch?v=LTL8NbpROwM 367
124 1. Jewish Ethnicity & DNA: History, Migration, Genetics Schelly Talalay Dardashti https://www.youtube.com/watch?v=AIJyphGEZTA 82

 

125 2. Jewish Ethnicity & DNA: History, Migration, Genetics Schelly Talalay Dardashti https://www.youtube.com/watch?v=VM3MCYM0hkI 72
126 Ask us about DNA Talking Family History (live) https://www.youtube.com/watch?v=kv_RfR6OPpU 96 plus live viewers
127 1. An Introduction to Visual Phasing Tanner Blair Tolman https://www.youtube.com/watch?v=WNhErW5UVKU

 

183
128 2. An Introduction to Visual Phasing Tanner Blair Tolman https://www.youtube.com/watch?v=CRpQ8EVOShI 110

 

129 Common Problems When Doing Visual Phasing Tanner Blair Tolman https://www.youtube.com/watch?v=hzFxtBS5a8Y 68
130 Cross Visual Phasing to Go Back Another Generation Tanner Blair Tolman https://www.youtube.com/watch?v=MrrMqhfiwbs 64
131 DNA Basics Tanner Blair Tolman https://www.youtube.com/watch?v=OCMUz-kXNZc 155
132 DNA Painter and Visual Phasing Tanner Blair Tolman https://www.youtube.com/watch?v=2-eh1L4wOmQ 155
133 DNA Painter Part 2: Chromosome Mapping Tanner Blair Tolman https://www.youtube.com/watch?v=zgOJDRG7hJc 172
134 DNA Painter Part 3: The Inferred Segment Generator Tanner Blair Tolman https://www.youtube.com/watch?v=96ai8nM4lzo

 

100
135 DNA Painter Part 4: The Distinct Segment Generator Tanner Blair Tolman https://www.youtube.com/watch?v=Pu-WIEQ_8vc 83
136 DNA Painter Part 5: Ancestral Trees Tanner Blair Tolman https://www.youtube.com/watch?v=dkYDeFLduKA 73
137 Understanding Your DNA Ethnicity Results Tanner Blair Tolman https://www.youtube.com/watch?v=4tAd8jK6Bgw 518
138 What’s New at GEDmatch Tim Janzen https://www.youtube.com/watch?v=AjA59BG_cF4

 

515
139 What Does it Mean to Have Neanderthal Ancestry? Ugo Perego https://www.youtube.com/watch?v=DshCKDW07so 190
140 Big Y-700 Your DNA Guide https://www.youtube.com/watch?v=rIFC69qswiA 143
141 Next Steps with Your DNA Your DNA Guide – Diahan Southard (live) https://www.familysearch.org/rootstech/session/next-steps-with-your-dna Not yet available

Additions:

142  Adventures of an Amateur Genetic Genealogist – Geoff Nelson https://www.familysearch.org/rootstech/session/adventures-of-an-amateur-genetic-genealogist     291 views

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AutoKinship at GEDmatch by Genetic Affairs

Genetic Affairs has created a new version of AutoKinship at GEDmatch. The new AutoKinship report adds new features, allows for more kits to be included in the analysis, and integrates multiple reports together:

  • AutoCluster – the autoclusters we all know and love
  • AutoSegment – clusters based on segments
  • AutoTree – reconstructed tree based on GEDCOM files of you and your matches, even if you don’t have a tree
  • AutoKinship – the original AutoKinship report provided genetic trees. The new AutoKinship report includes AutoTree, combines both, and adds features called AutoKinship Tree. (Trust me on this one – you’ll see in a minute!)
  • Matches
    • Common Ancestors with your ancestors
    • Common Ancestors between matches, even if they don’t match your tree
    • Common Locations

Maybe the best news is that some reports provide automatic triangulation because, at GEDmatch, it’s possible to not only see how you match multiple people, but also if those people match each other on that same segment. Of course, triangulation requires three-way matching in addition to the identification of common ancestors which is part of what AutoKinship provides, in multiple ways.

Let’s step through the included reports and features one at a time, using my clusters as an example.

Order Your Report

As a Tier 1 GEDmatch customer, sign in, select AutoKinship and order your report.

Note that there are now two clustering settings, the default setting and one that will provide more dense clusters. The last setting is the default setting for AutoKinship, since it has been shown to produce better AutoKinship results.

You can also select the number of kits to consider. Since this tool is free with a GEDmatch Tier 1 subscription, you can start small and rerun if you wish, as often as you wish.

Currently, a maximum of 500 matches can be included, but that will be increased to 1000 in the future. Your top 500 matches will be included that fall within the cM matching parameters specified.

I’m leaving this at the maximum 400 cM threshold, so every match below that is included. I generally leave this default threshold because otherwise my closest matches will be in a huge number of clusters which may cause processing issues.

For a special use case where you will want to increase the cM threshold, see the Special Use Cases section near the end of this article.

You can select a low number of matches, like 25 or 50 which is particularly useful if you want to examine the closest matches of a kit without a tree.

Keep in mind that there is currently a maximum processing time of 10 minutes allowed per report. This means that if you have large clusters, which are the last ones processed, you may not have AutoKinship results for those clusters.

This also means that if you select a high cM threshold and include all 500 allowable matches, you will receive the report but the AutoKinship results may not be complete.

When finished, your report will be delivered to you as a download link with an attached zipped file which you will need to save someplace where you can find it.

Unzip

If you’re a PC user, you’ll need to unzip or extract the files before you can use the files. You’ll see the zipper on the file.

If you don’t extract the contents, you can click on the file to open which will display a list of the files, so it looks like the files are extracted, but they aren’t.

You can see that the file is still zipped.

You can click on the html file which will display the AutoCluster correctly too, but when you click on any other link within that file, you’ll receive this error message if the file is still zipped.

If this happens to you, it means the file is still zipped. Close the files you have open, right click on the yellow zipped file folder and “extract all.”

Then click on the HTML link again and everything should work.

Ok, on to the fun part – the tools.

Tools

I’ve written about most of these tools individually before, except for the new combinations of course. I’ve put all of the Genetic Affairs Tools, Instructions and Resources in one article that you can find here.

I recommend that you take a look to be sure you’re using each tool to its greatest advantage.

AutoCluster

Click on the html file and watch your AutoCluster fly into place. I always, always love this part.

The first thing I noticed about my AutoCluster at GEDmatch is that it’s HUGE! I have a total of 144 clusters and that’s just amazing!

Information about the cluster file, including the number of matches, maximum and minimum cM used for the report, and minimum cluster size appears beneath your cluster chart.

22 people met the criteria but didn’t have other matches that did, so they are listed for my review, but not included in the cluster chart.

At first glance, the clusters look small, but don’t despair, they really aren’t.

My clusters only look small because the tool was VERY successful, and I have many matches in my clusters. The chart has to be scaled to be able to display on a computer monitor.

New Layout

Genetic Affairs has introduced a new layout for the various included tools.

Each section opens to provide a brief description of the tool and what is occurring. This new tool includes four previous tools plus a new one, AutoCluster Tree, as follows:

AutoCluster

AutoCluster first organizes your DNA matches into shared match clusters that likely represent branches of your family. Everyone in a cluster will likely be on the same ancestral line, although the MRCA between any of the matches and between you and any match may vary. The generational level of the clusters may vary as well. One may be your paternal grandmother’s branch, another may be your paternal grandfather’s father’s branch.

AutoSegment

AutoSegment organizes your matches based on triangulating segments. AutoSegment employs the positional information of segments (chromosome and start and stop position) to identify overlapping segments in order to link DNA matches. In addition, triangulated data is used to collaborate these links. Using the user defined minimum overlap of a DNA segment we perform a clustering of overlapping DNA segments to identify segment clusters. The overlap is calculated in centimorgans using human genetic recombination maps. Another aspect of overlapping segments is the fact that some regions of our genome seem to have more matches as compared to the other regions. These so-called pile-up areas can influence the clustering. The removal of known pile-up regions based on the paper of Li et al 2014 is optional and is not performed for this analysis However, a pileup report is provided that allows you to examine your genome for pileup regions.

AutoTree

By comparing the tree of the tested person and the trees from the members of a certain cluster, we can identify ancestors that are common amongst those trees. First, we collect the surnames that are present in the trees and create a network using the similarity between surnames. Next, we perform a clustering on this network to identify clusters of similar surnames. A similar clustering is performed based on a network using the first names of members of each surname cluster. Our last clustering uses the birth and death years of members of a cluster to find similar persons. As a consequence, initially large clusters (based on the surnames) are divided up into smaller clusters using the first name and birth/death year clustering.

AutoKinship

AutoKinship automatically predicts family trees based on the amount of DNA your DNA matches share with you and each other. Note that AutoKinship does not require any known genealogical trees from your DNA matches. Instead, AutoKinship looks at the predicted relationships between your DNA matches, and calculates many different paths you could all be related to each other. The probabilities used by this AutoKinship analysis are based on simulated data for GEDmatch matches and are kindly provided by Brit Nicholson (methodology described here). Based on the shared cM data between shared matches, we create different trees based on the putative relationships. We then use the probabilities to test every scenario which are then ranked.

AutoKinship Tree

Predicted trees from the AutoTree analysis are based on genealogical trees shared by the DNA matches and, if available, shared by the tested person. The relationships between DNA matches based on their common ancestors as provided AutoTree are used to perform an AutoKinship analysis and are overlayed on the predicted AutoKinship tree.

AutoKinship Tree is New

AutoKinship Tree is the new feature that combines the features of both AutoTree and AutoKinship. You receive:

  • Common ancestors between you and your matches
  • Trees of people who don’t share your common ancestors but share ancestors with each other
  • Combined with relationship predictions and
  • A segment analysis

Of course, the relative success of the tree tools depends upon how many people have uploaded GEDCOM files.

Big hint, if you haven’t uploaded your family tree, do so now. If you are an adoptee or searching for a parent and don’t know who your ancestors are, AutoKinship Tree does its best without your tree information, and you will still benefit from the trees of others combined with predicted relationships based on DNA.

It’s easier to show you than to tell you, so let’s step through my results one section at a time.

I’m going to be using cluster 5 which has 32 members and cluster 136 which has 8 members. Ironically, cluster 136 is a much more useful cluster, with 8 good matches, than cluster 5 which includes 32 people.

Results of the AutoKinship Analyses

As you scroll down your results, you’ll see a grid beneath the Explanation area.

It’s easy to see which cluster received results for each tool. My cluster 5 has results in each category, along with surnames. (Notice that you can search for surnames which displays only the clusters that contain that surname.)

I can click on each icon to see what’s there waiting for me.

Additionally, you can click at the top on the blue middle “here” for an overview of all common ancestors. Who can resist that, right?

Click on the ancestor’s name or the tree link to view more information.

You can also view common locations too by clicking on the blue “here” at far right. A location, all by itself, is a HUGE hint.

Clicking on the tree link shows you the tree of the tester with ancestors at that location. I had several others from North Carolina, generally, and other locations specifically. Let’s take a look at a few examples.

Common Ancestor Clusters

Click on the first blue link to view all common ancestors.

Common Ancestor Clusters summarize all of the clusters by ancestor. In other words, if any of your matches have ancestors in common in their tree, they are listed here.

These clusters include NOT just the people who share ancestors in a tree with you, but who also share known ancestors with each other BUT NOT YOU. That may be incredibly important when you are trying to identify your ancestors – as in brick walls. Your ancestors may be their ancestors too, or your common segments might lead to your common ancestors if you complete their tree.

There are other important hints too.

In my case, above, Jacob Lentz is my known ancestor.

However, Sarah Barron is not my ancestor, nor is John Vincent Dodson. They are the descendants of my Dodson ancestor though. I recognized that surname and those people. In other instances, recognizing a common geography may be your clue for figuring out how you connect.

In the cluster column at left, you can see the cluster number in which these people are found.

Common Locations Table

Clicking on the second link provides a Common Location Table

Some locations are general, like a state, and others are town, county or even village names. Whatever people have included in their GEDCOM files that can be connected.

Looking at this first entry, I recognize some of the ancestral surnames of Karen’s ancestors. The fact that we are found in the same cluster and share DNA indicates a common ancestor someplace.

Check for this same person in additional locations, then, look at their tree.

Ok, back to the AutoKinship Analysis Table and Cluster 136.

Cluster 136

I’m going to use Cluster 136 as an example because this cluster has generated great reports using all of the tools, indicated by the icon under each column heading. Some clusters won’t have enough information for everything so the tools generate as much as possible.

Scrolling down to Cluster 136 in the AutoCluster Information report, just beneath the list of clusters, I can see my 8 matches in that cluster.

Of course, I can click on the links for specific information, or contact them via email. At the end of this article in the “Tell Me Everything” section, I’ll provide a way to retrieve as much information as possible about any one match. For now, let’s move to the AutoTree.

Cluster 136 AutoTree

Clicking on the icon under AutoTree shows me how two of the matches in this cluster are related to each other and myself.

Note that the centimorgan badges listed refer to the number of cM that I share with each of these people, not how much they share with each other.

Click on any of the people to see additional information.

When I click on J Lentz m F Moselman, a popup box shows me how this couple is related to me and my matches.

Of course, you can also view the Y DNA or mitochondrial DNA haplogroups if the testers have provided that information when they set up their GEDmatch profile information.

Just click on the little icons.

If the testers have not provided that information, you can always check at FamilyTreeDNA or 23andMe, if they have tested at either of those vendors, to view their haplogroup information.

Today, GEDmatch kit numbers are assigned randomly, but in the early days, before Genesis, the leading letter of A meant AncestryDNA, F or T for FamilyTreeDNA, M for 23andMe and H for MyHeritage. If the kit number is something else, perform a one-to-one or a one-to-many report which will display the source of their DNA file.

The small number, 136 in this case, beside the cM number indicates the cluster or clusters that these people are members of. Some people are members of multiple clusters

Let’s see what’s next.

Cluster 136 Common Ancestors

Clicking on the Ancestors icon provides a report that shows all of the Ancestor Clusters in cluster 136.

The difference between this ancestor chart and the larger chart is that this only shows ancestors for cluster 136, while the larger chart shows ancestors for the entire AutoCluster report.

Cluster 136 Locations

All of the locations shown are included in trees of people who cluster together in cluster 136. Of course, this does NOT mean that these locations are all relevant to cluster 136. However, finding my own tree listed might provide an important clue.

Using the location tool, I discover 5 separate location clusters. This location cluster includes me with each tester’s ancestors who are found in Montgomery County, Ohio.

The difference between this chart for cluster 136 only and the larger location chart is that every location in this chart is relevant for people who all cluster together meaning we all share some ancestral line.

Viewing the trees of other people in the cluster may suggest ancestors or locations that are essential for breaking down brick walls.

Cluster 136 AutoKinship

Clicking on the anchor in the AutoKinship column provides a genetically reconstructed tree based on how closely each of the people match me, and each other. Clearly, in order to be able to provide this prediction, information about how your matches also match each other, or don’t, is required.

Again, the cM amount shown is the cM match with me, not with each other. However, if you click on a match, a popup will be shown that shows the shared cM between that person and the other matches as well as the relationship prediction between them in this tree

So, Bill matches David with a total of 354.3 cM and they are positioned as first cousins once removed in this tree. The probability of the match being a 1C1R (first cousin once removed) is 64.9%, meaning of course that other relationships are possible.

Note that Bill and David ALSO share a segment with me in autosegment cluster 185, on chromosome 3.

It’s important to note that while 136 is the autocluster number, meaning that colored block on the report, WITHIN clusters, autosegment clusters are formed and numbered. 

Each autosegment cluster receives its own number and the numbers are for the entire report. You will have more autosegment clusters than autoclusters, because at least some of the colorful autoclusters will contain more than one segment cluster.

Remember, autoclusters are those colorful boxes of matches that fly into place. Autosegment clusters are the matching triangulated clusters on chromosomes and they are represented by the blue bars, shown below.

AutoCluster 136 contains 5 different autosegment clusters, but Bill is only included in one of those autosegment clusters.

You’ll notice that there are some people, like Robin at the bottom, who do match some other people in the cluster, but either not enough people, or not enough overlapping DNA to be included as an autocluster member.

The small colored chromosomes with numbers, boxed in red, indicate the chromosome on which this person matches me.

If you click on that chromosome icon, you’ll see a popup detailing everyone who matches me on that segment.

Note that in some cases a member of a segment cluster, like Robin, did not make it in the AutoCluster cluster. You can spot these occurrences by scrolling down and looking at the cluster column which will then be empty for that particular match.

Reconstructed AutoKinship Trees in Most Likely Order

Scrolling down the page, next we see that we have multiple possible trees to view. We are shown the most likely tree first.

Tree likelihood is constructed based on the combined probability of my matching cM to an individual plus their likely relationship to each other based on the amount of DNA they share with each other as well.

In my case, all of the first 8 trees are equally as likely to be accurate, based on autosomal genetic relationships only. The ninth tree is only very slightly less likely to be accurate.

The X chromosome is not utilized separately in this analysis, nor are Y or mitochondrial DNA haplogroups if provided.

DNA Relationship Matrix

Continuing to scroll down, we next see the DNA matrix that shows relationships for cluster 5 in a grid format. Click on “Download Relationship Matrix” to view in a spreadsheet.

Keep scrolling for the next view which is the Individual Segment Cluster Information

Individual Segment Cluster Information

Remember that we are still focused on only one cluster – in this case, cluster 136. Each cluster contains people who all match at least some subset of other people in the cluster. Some people will match each other and the tested person on the same chromosome segment, and some won’t. What we generally see within clusters are “subclusters” of people who match each other on different chromosomes and segments. Also, some matches from cluster 136 might match other people but those matches might not be a member of cluster 136.

In autocluster 136, I have 14 DNA segments that converge into 5 segment clusters with my matches. Here’s segment cluster 185 that consists of two people in addition to me. Note that for individuals to be included in these segment clusters at GEDmatch, they must triangulate with people in the same segment cluster.

From left to right, we see the following information:

  • AutoCluster number 136, shown below

  • Segment cluster 185. This is a segment cluster within autocluster 136.

  • Segment cluster 185 occurs on chromosome 3, between the designated start and stop locations.
  • The segment representation shows the overlapping portions of the two matches, to me. You can easily see that they overlap almost exactly with each other as well.
  • The SNP count is shown, followed by the name and cM count.

Cluster 136 AutoKinship Tree

The AutoKinship Tree column is different from the AutoKinship column in one fundamental way. The new AutoKinship Tree feature combines the genealogical AutoTree and the genetic AutoKinship output together in one report.

You can see that the “prior” genealogical tree information that one of my matches also descends from Jacob Lentz (and wife, if you click further) has now been included. The matches without trees have been reconstructed around the known genealogy based on how they match me and each other.

I was already aware of how I’m related to Bill, David, *C and *R, but I don’t know how I am related to these other people. Based on their kit identifier, I can go to the vendor where they tested and utilize tools there, and I can check to see if they have uploaded their DNA files elsewhere to discover additional records information or critical matches. Now at least I know where in the tree to search.

Cluster 136 AutoSegment

Clicking on AutoSegment provides you with segment information. Each cluster is painted on your chromosomes.

By hovering over the darkly colored segments, which are segment clusters, you can view who you match, although to view multiple matches, continue scrolling.

In the next section, you’ll see the two segment clusters contained wholly within cluster 136.

Following that is the same information for segment clusters partially linked to cluster 136, but not contained wholly within 136.

Bonus – Tell Me Everything – Individual Match Clusters

We’ve focused specifically on the AutoKinship tools, but if you’re interested in “everything” about one specific match, you can approach things from that perspective too. I often look at a cluster, then focus on individuals, beginning with those I can identify which focuses my search.

If you click on any person in your match list, you’ll receive a report focusing on that person in your autocluster.

Let’s use cousin Bill as an example. I know how he’s related to me.

You can choose to display your chosen cluster by:

  • Cluster
  • Number of shared matches
  • Shared cM with the tester
  • Name

I would suggest experimenting with all of the options and see which one displays information that is most useful to the question you’re trying to answer.

Beneath the cluster for Bill, you’ll see the relevant information about the cluster itself. Bill has cluster matches on two different chromosomes.

The AutoCluster Cluster member Information report shows you how much DNA each cluster member shares with the tested person, which is me, and with each other cluster member. It’s easy to see at a glance who Bill is most closely related to by the number of cMs shared.

Only one of Bill’s chromosomes, #3, is included in clusters, but this tells me immediately that this/these segments on chromosome 3 triangulate between me, Bill, and at least one other person.

Segments shown in orange (chromosome 22) match me, but are not included in a cluster.

Special Use Cases – Unknown People

For adoptees and people trying to figure out how they are related to closer relatives, especially those without a tree, this new combined AutoKinship tool is wonderful.

400 cM is the upper default limit when running the report, meaning that close family members will not be included because they would be included in many clusters. However, you can make a different selection. If you’re trying to determine how several closely related people intersect, select a high threshold to include everyone.

Select a lower number of matches, like 25 or 50.

In this example, ‘no limit” was selected as the upper total match threshold and 25 closest matches.

AutoKinship then constructs a genetic tree and tells you which trees are possible and most likely. If some people do have trees, that common ancestor information would be included as well.

Note that when matches occur over the 400 cM threshold, there will be too many common chromosome matches so the chromosome numbers are omitted. Just check the other reports.

This tool would have helped a great deal with a recent close match who didn’t know how they are related to my family.

You can see this methodology in action and judge its accuracy by reconstructing your own family, assuming some of your known family members have uploaded to GEDmatch. Try it out.

It’s a Lot!

I know there’s a lot here to absorb, but take your time and refer back to this article as needed.

This flexible new tool combines DNA matching, genealogy trees, genetic trees, locations, autoclusters, a chromosome browser, and triangulation. It took me a few passes and working with different clusters to understand and absorb the information that is being provided.

For people who don’t know who their parents or close relatives are, these tools are amazing. Not only can they determine who they are related to, and who is related to each other, but with the use of trees, they can view common ancestors which provides possible ancestors for them too.

For people painting their triangulated segments at DNAPainter, AutoKinship provides triangulation groups that can be automatically painted using the Cluster Auto Painter, here, plus helps to identify that common ancestor. You can read more about DNAPainter, here.

For people seeking to break down brick walls, AutoKinship Tree provides assistance by providing tree matching between your matches for common ancestors NOT IN YOUR TREE, but that ARE in theirs. Your brick walls are clearly not (yet) identified in your tree, although that’s our fervent hope, right?

Even if your matches’ trees don’t go far enough back, as a genealogist, you can extend those trees further to hopefully reveal a previously unknown common ancestor.

The Best Things You Can Do

Aside from DNA testing, the three best things you can do to help yourself, and your clusters are:

  • Upload your GEDCOM file, complete with locations, so you have readily available trees. Ask your matches to do so as well. Trees help you and others too.
  • Encourage people you match at Ancestry who provides no chromosome segment information or chromosome browser to upload a copy of their DNA files and tree.
  • Test your family members and cousins, and encourage them to upload their DNA and their trees. Offer to assist them. You can find step-by-step download/upload instructions here.

Have fun!

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AutoSegment Triangulation Cluster Tool at GEDmatch

Today, I’m reviewing the exciting new AutoSegment Triangulation Cluster Tool at GEDmatch. I love it because this automated tool can be as easy or complex as you want.

It’s easy because you just select your options, run it, and presto, you receive all kinds of useful results. It’s only complex if you want to understand the details of what’s really happening beneath the hood, or you have a complex problem to unravel. The great news is that this one tool does both.

I’ve taken a deep dive with this article so that you can use AutoSegment either way.

Evert-Jan “EJ” Blom, creator of Genetic Affairs has partnered with GEDmatch to provide AutoSegment for GEDmatch users. He has also taken the time to be sure I’ve presented things correctly in this article. Thanks, EJ!

My recommendation is to read this article by itself first to understand the possibilities and think about how you can utilize these results. Then, at GEDmatch, select the AutoSegment Report option and see what treasures await!

Genetic Affairs

Genetic Affairs offers a wide variety of clustering tools that help genealogists break down their brick walls by showing us, visually, how our matches match us and each other. I’ve written several articles about Genetic Affairs’ tools and how to use them, here.

Every DNA segment that we have originated someplace. First, from one of our parents, then from one of our 4 grandparents, and so forth, on up our tree. The further back in time we go, the smaller the segments from those more distant ancestors become, until we have none for a specific ancestor, or at least none over the matching threshold.

The keyword in that sentence is segment, because we can assign or attribute DNA segments to ancestors. When we find that we match someone else on that same segment inherited from the same parent, assuming the match is identical by descent and not identical by chance, we then know that somehow, we shared a common ancestor. Either an ancestor we’ve already identified, or one that remains a mystery.

Those segments can and will reveal ancestors and tell us how we are related to our matches.

That’s the good news. The bad news is that not every vendor provides segment information. For example, 23andMe, FamilyTreeDNA, and MyHeritage all do, but Ancestry does not.

For Ancestry testers, and people wishing to share segment information with Ancestry testers, all is not lost.

Everyone can download a copy of their raw DNA data file and upload those files to vendors who accept uploads, including FamilyTreeDNA, MyHeritage, and of course GEDmatch.

GEDmatch

GEDmatch does not offer DNA testing services, specializing instead in being the common matching denominator and providing advanced tools. GEDmatch recently received a facelift. If you don’t recognize the image above, you probably haven’t signed in to GEDmatch recently, so take a look. The AutoSegment tool is only available on the new version, not the Classic version.

Ancestry customers, as well as people testing elsewhere, can download their DNA files from the testing vendor and upload the files to GEDmatch, availing themselves of both the free and Tier 1 subscription tools.

I’ve written easy step-by-step download/upload instructions for each vendor, here.

At GEDmatch, matching plus a dozen tools are free, but the Tier 1 plan for $10 per month provides users with another 14 advanced tools, including AutoSegment.

To get started, click on the AutoSegment option.

AutoSegment at GEDmatch

You’ll see the GEDmatch AutoSegment selection menu.

You can easily run as many AutoSegment reports as you want, so I suggest starting with the default values to get the lay of the land. Then experiment with different options.

At GEDmatch, AutoSegment utilizes your top 3000 matches. What a huge, HUGE timesaver.

Just a couple of notes about options.

  • My go-to number of SNPs is 500 (or larger,) and I’m always somewhat wary of matches below that level because there is an increased likelihood of identical by chance segments when the required number of segment matching locations is smaller.
  • GEDmatch has to equalize DNA files produced by different vendors, including no-calls where certain areas don’t read. Therefore, there are blank spaces in some files where there is data in other vendors’ files. The “Prevent Hard Breaks” option allows GEDmatch to “heal” those files by allowing longer stretches of “missing” DNA to be considered a match if the DNA on both sides of that blank space matches.
  • “Remove Segments in Known Pile-Up Regions” is an option that instructs GEDmatch NOT to show segments in parts of the human genome that are known to have pile-up regions. I generally don’t select this option, because I want to see those matches and determine for myself if they are valid. We’ll look at a few comparative examples in the Pileup section of this article.

Fortunately, you can experiment with each of these settings one by one to see how they affect your matching. Even if you don’t normally subscribe to GEDmatch, you can subscribe for only one month to experiment with this and other Tier 1 tools.

Your AutoSegment results will be delivered via a download link.

Save and Extract

All Genetic Affairs cluster files are delivered in a zipped file.

You MUST DO TWO THINGS, or these files won’t work correctly.

  1. Save the zip file to your computer.
  2. Extract the files from the zip file. If you’re on a PC, right-click on the zip file and EXTRACT ALL. This extracts the files from the zipped file to be used individually.

If you click on a feature and receive an error message, it’s probably because you either didn’t save the file to your computer or didn’t extract the files.

The file name is very long, so if you try to add the file to a folder that is also buried a few levels deep on your system, you may encounter problems when extracting your file. Putting the file on your desktop so you can access it easily while working is a good idea.

Now, let’s get to the good stuff.

Your AutoSegment Cluster File

Click on the largest HTML file in the list of your extracted files. The HTML file uses the files in the clusters and matches folders, so you don’t need to open those individually.

It’s fun to watch your clusters fly into place. I love this part.

If your file is too large and your system is experiencing difficulty or your browser locks, just click on the smaller AutoSegment HTML file, at the bottom of the list, which is the same information minus the pretty cluster.

Word to the wise – don’t get excited and skip over the three explanatory sections just below your cluster. Yes, I did that and had to go back and read to make sense of what I was seeing.

At the bottom of this explanatory section is a report about Pileup Regions that I’ll discuss at the end of this article.

Excel

As a third viewing option, you can also open the AutoSegment Excel file to view the results in an excel grid.

You’ll notice a second sheet at the bottom of this spreadsheet page that says AutoSegment-segment-clusters. If you click on that tab, you’ll see that your clusters are arranged in chromosome and cluster order, in the same format as long-time genetic genealogist Jim Bartlett uses in his very helpful blog, segment-ology.

You’ll probably see a message at the top of the spreadsheet asking if you want to enable editing. In order for the start and end locations to calculate, you must enable editing. If the start and end locations are zeroes, look for the editing question.

Notice that the colors on this sheet are coordinated with the clusters on the first sheet.

EJ uses yellow rows as cluster dividers. The “Seg” column in the yellow row indicates the number of people in this cluster group, meaning before the next yellow divider row. “Chr” is the chromosome. “Segment TG” is the triangulation group number and “Side” is Jim Bartlett’s segment tracking calculation number.

Of course, the Centimorgans column is the cM size, and the number of matching SNPs is provided.

You can read about how Jim Bartlett tracks his segment clusters, here, which includes discussions of the columns and how they are used.

Looking at each person in the cluster groups by chromosome, *WS matches me and *Cou, the other person in the cluster beginning and ending at the start and end location on chromosome 1. In the match row (as compared with the yellow dividing row,) Column F, “Seg,” tells you the number of segments where *WA matches me, the tester.

A “*” before the match name at GEDmatch means a pseudonym or alias is being used.

In order to be included in the AutoSegment report, a match must triangulate with you and at least one other person on (at least) one of those segments. However, in the individual match reports, shown below, all matching segments are provided – including ones NOT in segment clusters.

Individual DNA Matches

In the HTML file, click on *WA.

You’ll see the three segments where *WA matches you, or me in this case. *WA triangulates with you and at least one other person on at least one of these segments or *WA would not be included in the GEDmatch AutoSegment report.

However, *WA may only triangulate on one segment and simply match you on the other two – or *WA may triangulate on more than one segment. You’ll have to look at the other sections of this report to make that determination.

Also, remember that this report only includes your top 3000 matches.

AutoSegment

All Genetic Affairs tools begin with an AutoCluster which is a grouping of people who all match you and some of whom match each other in each colored cluster.

AutoSegment at GEDmatch begins with an AutoCluster as well, but with one VERY IMPORTANT difference.

AutoSegment clusters at GEDmatch represent triangulation of three people, you and two other people, in AT LEAST ONE LOCATION. Please note that you and they may also match in other locations where three people don’t triangulate.

By matching versus triangulation, I’m referring to the little individual cells which show the intersection of two of your matches to each other.

Regular AutoCluster reports, meaning NOT AutoSegment clusters at GEDmatch, include overlapping segment matches between people, even if they aren’t on the same chromosome and/or don’t overlap entirely. A colored cell in AutoSegment at GEDmatch means triangulation, while a colored cell in other types of AutoCluser reports means match, but not necessarily triangulation.

Match information certainly IS useful genealogically, but those two matching people in that cell:

  • Could be matching on unrelated chromosomes.
  • Could be matching due to different ancestors.
  • Could be matching each other due to an ancestor you don’t have.
  • May or may not triangulate.

Two people who have a colored cell intersection in an AutoSegment Cluster at GEDmatch are different because these cells don’t represent JUST a match, they represent a TRIANGULATED match.

Triangulation tightens up these matches by assuring that all three people, you and the two other people in that cell, match each other on a sufficient overlapping segment (10 cM in this case) on the same chromosome which increases the probability that you do in fact share a common ancestor.

I wrote about the concept of triangulation in my article about triangulation at GEDmatch, but AutoSegment offers a HUGE shortcut where much of the work is done for you. If you’re not familiar with triangulation, it’s still a good idea to read that article, along with A Triangulation Checklist Born From the Question; “Why NOT use Close Relatives for Triangulation?”

Let’s take a look at my AutoSegment report from GEDmatch.

AutoSegment Clusters at GEDmatch

A total of 195 matches are clustered into a total of 32 colored clusters. I’m only showing a portion of the clusters, above.

I’ve blurred the names of my matches in my AutoSegment AutoCluster, of course, but each cell represents the intersection of two people who both match and triangulate with me and each other. If the two people match and triangulate with each other and others in the same cluster, they are colored the same as their cluster matches.

For example, all 18 of the people in the orange cluster match me and each other on one (or more) chromosome segments. They all triangulate with me and at least one other person, or they would not appear in a colored cell in this report. They triangulate with me and every other person with whom they have a colored cell.

If you mouse over a colored cell, you can see the identity of those two people at that intersection and who else they match in common. Please note that me plus the two people in any cell do triangulate. However, me plus two people in a different cell in the same cluster may triangulate on a different segment. Everyone matches in an intricate grid, but different segments on different chromosomes may be involved.

You can see in this example that my cousin, Deb matches Laurene and both Deb and Laurene match these other people on a significant amount of DNA in that same cluster.

What happens when people match others within a cluster, but also match people in other colored clusters too?

Multiple Cluster Matches = Grey Cells

The grey cells indicate people who match in multiple clusters, showing the match intersection outside their major or “home” cluster. When you see a grey cell, think “AND.” That person matches everyone in the colored cell to the left of that grey cell, AND anyone in a colored cell below grey cells too. Any of your matches could match you and any number of other people in other cells/clusters as well. It’s your lucky day!

Deb’s matches are all shown in row 4. She and I both match all of the orange cluster people as well as several others in other clusters, indicated by grey cells.

I’m showing Deb’s grey cell that indicates that she also matches people in cluster #5, the large brown cluster. When I mouse over that grey cell, it shows that Deb (orange cluster) and Daniel (brown cluster) both match a significant number of people in both clusters. That means these clusters are somehow connected.

Looking at the bigger picture, without mousing over any particular cell, you can see that a nontrivial number of people match between the first several clusters. Each of these people match strongly within their primary-colored cluster, but also match in at least one additional cluster. Some people will match people in multiple clusters, which is a HUGE benefit when trying to identify the source ancestor of a specific segment.

Let’s look at a few examples. Remember, all of these people match you, so the grid shows how they also match with each other.

#1 – In the orange cluster, the top 5 rows, meaning the first 5 people on the left side list match other orange cluster members, but they ALSO match people in the brown cluster, below. A grey cell is placed in the column of the person they also match in the brown cluster.

#2 – The two grey cells bracketed in the second example match someone in the small red cluster above, but one person also matches someone in the small purple cluster and the other person matches someone in the brown cluster.

#3 – The third example shows one person who matches a number of people in the brown cluster in addition to every person in the magenta cluster below.

#4 – This long, bracketed group shows several people who match everyone in the orange cluster, some of whom also match people in the green cluster, the red cluster, the brown cluster, and the magenta cluster. Clearly, these clusters are somehow related to each other.

Always look at the two names involved in an individual cell and work from there.

The goal, of course, is to identify and associate these clusters with ancestors, or more specifically, ancestral couples, pushing back in time, as we identify the common ancestors of individuals in the cluster.

For example, the largest orange cluster represents my paternal grandparents. The smaller clusters that have shared members with the large orange cluster represent ancestors in that lineage.

Identifying the MRCA, or most recent common ancestor with our matches in any cluster tells us where those common segments of DNA originated.

Chromosome Segments from Clusters

As you scroll down below your cluster, you’ll notice a section that describes how you can utilize these results at DNAPainter.

While GEDmatch can’t automatically determine which of your matches are maternal and paternal, you can import them, by colored cluster, to DNAPainter where you can identify clusters to ancestors and paint them on your maternal and paternal chromosomes. I’ve written about how to use DNAPainter here.

Let’s scroll to the next section in your AutoSegment file.

Chromosome Segment Statistics

The next section of your file shows “Chromosome segment statistics per AutoSegment cluster.”

I need to take a minute here to describe the difference between:

  1. Colored clusters on your AutoCluster diagram, shown below, and
  2. Chromosome segment clusters or groups within each colored AutoSegment cluster

Remember, colored clusters are people, and you can match different people on different, sometimes multiple, chromosomes. Two people whose intersecting cell is colored triangulate on SOME segment but may also match on other segments that don’t triangulate with each other and you.

According to my “Chromosome segment statistics” report, my large orange AutoSegment cluster #1, above, includes:

  • 67 segments from all my matches
  • On five chromosomes (3, 5, 7, 10, 17)
  • That cluster into 8 separate chromosome segment clusters or groups within the orange cluster #1

This is much easier to visualize, so let’s take a look.

Chromosome Segment Clusters

Click on any cluster # in your report, above, to see the chromosome painting for that cluster. I’m clicking on my AutoSegment cluster #1 on the “Chromosome segment statistics” report that will reveal all of the segments in orange cluster #1 painted on my chromosomes.

The brightly colored painted segments show the triangulated segment locations on each chromosome. You can easily see the 8 different segment clusters in cluster #1.

Interestingly, three separate groups or chromosome clusters occur on chromosome 5. We’ll see in a few minutes that the segments in the third cluster on chromosome 5 overlaps with part of cluster #5. (Don’t confuse cluster number shown with a # and chromosome number. They are just coincidentally both 5 in this case.)

The next tool helps me visualize each of these segment clusters individually. Just scroll down.

You can mouse over the segment to view additional information, but I prefer the next tool because I can easily see how the DNA of the people who are included in this segment overlap with each other.

This view shows the individual chromosome clusters, or groups, contained entirely within the orange cluster #1. (Please note that you can adjust the column widths side to side by positioning the cursor at the edge of the column header and dragging.)

Fortunately, I recognize one of these matches, Deb, and I know exactly how she and I are related, and which ancestor we share – my great-grandparents.

Because these segments are triangulated, I know immediately that every one of these people share that segment with Deb and me because they inherited that segment of DNA from some common ancestor shared by me and Deb both.

To be very clear, these people may not share our exact same ancestor. They may share an ancestor upstream from Deb and my common ancestor. Regardless, these people, Deb, and I all share a segment I can assign at this point to my great-grandparents because it either came from them for everyone, or from an upstream ancestor who contributed it to one of my great-grandparents, who contributed it to me and Deb both.

Segment Clusters Entirely Linked

Clusters #2 and #3 are small and have common matches with people in cluster #1 as indicated by the grey cells, so let’s take a look.

I’m clicking on AutoSegment green cluster #2 which only has two cluster members.

I can see that the common triangulated segment between these two people and me occurs on chromosome 3.

This segment on chromosome 3 is entirely contained in green cluster #2, meaning no members of other clusters triangulate on this segment with me and these two people.

This can be a bit confusing, so let’s take it logically step by step.

Remember that the two people who triangulate in green cluster #2 also match people in orange cluster #1? However, the people from orange cluster #1 are NOT shown as members of green cluster #2.

This could mean that although the two people in the green cluster #2 match a couple of people in the orange cluster, they did not match the others, or they did not triangulate. This can be because of the minimum segment overlap threshold that is imposed.

So although there is a link between the people in the clusters, it is NOT sufficient for the green people to be included in the orange cluster and since the two matches triangulate on another segment, they become a separate green cluster.

In reality, you don’t need to understand exactly why members do or don’t fall into the clusters they do, you just need to understand generally how clustering and triangulation works. In essence, trust the tool if people are NOT included in multiple clusters. Click on each person individually to see which chromosomes they match you on, even if they don’t triangulate with others on all of those segments. At this point, I often run one-to-one matches, or other matching tools, to see exactly how people match me and each other.

However, if they ARE included in multiple partly linked clusters, that can be a HUGE bonus.

Let’s look at red cluster #3.

Segment Clusters Partly Linked

You can see that Mark, one of the members of red cluster #3 shares two triangulated segments, one on chromosome 4, and one on chromosome 10.

Mark and Glenn are members of cluster #3, but Glenn is not a member of the segment cluster/group on chromosome 4, only Iona and Mark.

Scrolling down, I can view additional information about the cluster members and the two segments that are held within red cluster #3.

Unlike green cluster #2 whose segment cluster/group is entirely confined to green cluster #2, red cluster #3 has NO segments entirely confined to members of red cluster #3.

Cluster #3 has two members, Mark and Glen. Mark and Glen, along with Val who is a member of orange cluster #1 triangulate on chromosome 10. Remember, I said that chromosome 10 would be important in a minute when we were discussing orange cluster #1. Now you know why.

This segment of chromosome 10 triangulates in both orange cluster #1 AND red cluster #3.

However, Mark, who is a red cluster #3 member also triangulates with Iona and me on a segment of chromosome 4. This segment also appears in AutoSegment brown cluster #4 on chromosome 4.

Now, the great news is that I know my earliest known ancestors with Iona, which means that I can assign this segment to my paternal great-great-grandparents.

If I can identify a common ancestor with some of these other people, I may be able to push segments back further in time to an earlier ancestral couple.

Identifying Common Ancestors

Of course, review each cluster’s members to see if you recognize any of your cousins.

If you don’t know anyone, how do you identify a common ancestor? You can email the person, of course, but GEDmatch also facilitates uploading GEDCOM files which are trees.

In your primary AutoSegment file, keep scrolling to see who has trees.

AutoSegment Cluster Information

If you continue to scroll down in your original HTML file, you’ll see AutoSegment Cluster Information.

For each cluster, all members are listed. It’s easy to see which people have uploaded trees. You can click to view and can hopefully identify an ancestor or at least a surname.

Click on “tree” to view your match’s entry, then on Pedigree to see their tree.

If your matches don’t have a tree, I suggest emailing and sharing what you do know. For example, I can tell my matches in cluster #1 that I know this line descends from Lazarus Estes and Elizabeth Vannoy, their birth and death dates and location, and encourage my match to view my tree which I have uploaded to GEDmatch.

If you happen to have a lot of matches with trees, you can create a tag group and run the AutoTree analysis on this tag group to identify common ancestors automatically. AutoTree is an amazing tool that identifies common ancestors in the trees of your matches, even if they aren’t in your tree. I wrote about AutoTree, here.

Pileup Regions

Whether you select “Remove Segments in Known Pileup Regions” or not when you select the options to run AutoSegment, you’ll receive a report that you can access by a link in the Explanation of AutoSegment Analysis section. The link is buried at the bottom of those paragraphs that I said not to skip, and many people don’t even see it. I didn’t at first, but it’s most certainly worth reviewing.

What Are Pileup Regions?

First, let’s talk about what pileup regions are, and why we observe them.

Some regions of the human genome are known to be more similar than others, for various reasons.

In these regions, people are more likely to match other people simply because we’re human – not specifically because we share a common ancestor.

EJ utilizes a list of pileup regions, based on the Li et al 2014 paper.

You may match other people on these fairly small segments because humans, generally, are more similar in these regions.

Many of those segments are too small to be considered a match by themselves, although if you happen to match on an adjacent segment, the pileup region could extend your match to appear to be more significant than it is.

If you select the “remove pileup segments” option, and you overlap any pileup region with 4.00 cM or larger, the entire matching segment that includes that region will be removed from the report no matter how large the matching segment is in total.

Here’s an example where the pileup region of 5.04 cM is right in the middle of a matching segment to someone. This entire 15.04 cM segment will be removed.

If those end segments are both 10 cM each instead of 5 cM, the segment will still be removed.

However, if the segment overlap with the pileup region is 3.99 cM or smaller, none of the resulting segment will be removed, so long as the entire segment is over the matching threshold in the first place. In the example above, if the AutoSegment threshold was 7 or 8 cM, the entire segment would be retained. If the matching threshold was 9 or greater, the segment would not have been included because of the threshold.

Of course, eight regions in the pileup chart are large enough to match without any additional adjacent segments if the match threshold is 7 cM and the overlap is exact. If the match threshold is 10 cM, only two pileup regions will possibly match by themselves. However, because those two regions are so large, we are more likely to see multiple matches in those regions.

Having a match in a pileup region does NOT invalidate that match. I have many matches in pileup regions that are perfectly valid, often extending beyond that region and attributable to an identified common ancestor.

You may also have pileup regions, in the regions shown in the chart and elsewhere, because of other genealogical reasons, including:

  • Endogamy, where your ancestors descend from a small, intermarried population, either through all or some of your ancestors. The Jewish population is probably the most well-known example of large-scale endogamy over a very long time period.
  • Pedigree collapse, where you descend from the same ancestors in multiple ways in a genealogical timeframe. Endogamy can reach far back in time. With pedigree collapse, you know who your ancestors are and how you descend, but with endogamy, you don’t.
  • Because you descend from an over-represented or over-tested group, such as the Acadians who settled in Nova Scotia in the early 1600s, intermarried and remained relatively isolated until 1755 when they were expelled. Their numerous descendants have settled in many locations. Acadian descendants often have a huge number of Acadian matches.
  • Some combination of all three of the above reasons. Acadians are a combination of both endogamy and pedigree collapse and many of their descendants have tested.

In my case, I have proportionally more Acadian matches than I have other matches, especially given that my Dutch and some of my German lines have few matches because they are recent immigrants with few descendants in the US. This dichotomy makes the proportional difference even more evident and glaring.

I want to stress here that pileup regions are not necessarily bad. In fact, they may provide huge clues to why you match a particular group of people.

Pileup Regions and Genealogy

In 2016, when Ancestry removed matches that involved personal pileup regions, segments that they felt were “too-matchy,” many of my lost matches were either Acadian or Mennonite/Brethren. Both groups are endogamous and experience pedigree collapse.

Over time, as I’ve worked with my DNA matches, painting my segments at DNAPainter, which marks pileup regions, I’ve come to realize that I don’t have more matches on segments spanning standard pileup regions indicated in the Li paper, nor are those matches unreliable.

An unreliable match might be signaled by people who match on that segment but descend from different unrelated common ancestors to me. Each segment tracks to one maternal and one paternal ancestral source, so if we find individuals matching on the same segment who claim descent from different ancestral lines on the same side, that’s a flag that something’s wrong. (That “something” could also be genealogy or descending from multiple ancestors.)

Therefore, after analyzing my own matching patterns, I don’t select the option to remove pileup segments and I don’t discount them. However, this may not be the right selection for everyone. Just remember, you can run the report as many times as your want, so nothing ventured, nothing gained.

Regardless of whether you select the remove pileup segments option or not, the report contents are very interesting.

Pileup Regions in the Report

Let’s take a look at Pileups in the AutoSegment report.

  • If I don’t select the option of removing pileup region segments, I receive a report that shows all of my segments.
  • If I do select the option to remove pileup region segments, here’s what my report says.

Based on the “remove pileup region segments” option selected, all segments should be removed in the pileup regions documented in the Li article if the match overlap is 4.00 cM or larger.

I want to be very clear here. The match itself is NOT removed UNLESS the pileup segment that IS removed causes the person not to be a match anymore. If that person still matches and triangulates on another segment over your selected AutoSegment threshold, those segments will still show.

I was curious about which of my chromosomes have the most matches. That’s exactly what the Pileup Report tells us.

According to the Pileup Report, my chromosome with the highest number of people matching is chromosome 5. The Y (vertical) axis shows the number of people that match on that segment, and the X axis across the bottom shows the match location on the chromosome.

You’ll recall that chromosome 5 was the chromosome from large orange AutoSegment cluster #1 with three distinct segment matches, so this makes perfect sense.

Sure enough, when I view my DNAPainter results, that first pileup region from about location 5-45 are Brethren matches (from my maternal grandfather) and the one from about 48-95 are Acadian matches (from my maternal grandmother.) This too makes sense.

Please note that chromosome 5 has no general pileup regions annotated in the Li table, so no segments would have been removed.

Let’s look at another example where some segments would be removed.

Based on the chromosome table from the Li paper, chromosome 15 has nearly back-to-back pileup regions from about 20-30 with almost 20 cM of DNA combined.

Let’s see what my Pileup Segment Removal Report for chromosome 15 shows.

No segment matches in this region are reported because I selected remove pileup regions.

The only way to tell how many segment matches were removed in this region is to run the report and NOT select the remove pileup segments option. I did that as a basis for comparison.

You can see that about three segments were removed and apparently one of those segments extended further than the other two. It’s also interesting that even though this is designated as a pileup region, I had fewer matches in this region than on other portions of the chromosome.

If I want to see who those segments belong to, I can just view my chromosome 15 results in the AutoSegment-segment-clusters tab in the spreadsheet view which is arranged neatly in chromosome order.

The only way to tell if matches in pileup regions are genealogically valid and relevant is to work with each match or group of matches and determine if they make sense. Does the match extend beyond the pileup region start and end edge? If so, how much? Can you identify a common ancestor or ancestral line, and if so, do the people who triangulate in that segment cluster makes sense?

Of course, my genealogy and therefore my experience will be different than other people’s. Anyone who descends primarily from an endogamous population may be very grateful for the “remove pileups” option. One size does NOT fit all. Fortunately, we have options.

You can run these reports as many times as you want, so you may want to run identical reports and compare a report that removes segments that occur in pileup regions with one that does not.

What’s Next?

For AutoSegment at GEDmatch to work most optimally, you’ll need to do three things:

  • If you don’t have one already, upload a raw DNA file from one of the testing vendors. Instructions here.
  • Upload a GEDCOM file. This allows you to more successfully run tools like AutoTree because your ancestors are present, and it helps other people too. Perhaps they will identify your common ancestor and contact you. You can always email your matches and suggest that they view your GEDCOM file to look for common ancestors or explain what you found using AutoTree. Anyone who has taken the time to learn about GEDmatch and upload a file might well be interested enough to make the effort to upload their GEDCOM file.
  • Convince relatives to upload their DNA files too or offer to upload for them. In my case, triangulating with my cousins is invaluable in identifying which ancestors are represented by each cluster.

If you have not yet uploaded a GEDCOM file to GEDmatch, now’s a great time while you’re thinking about it. You can see how useful AutoClusters and AutoSegment are, so give yourself every advantage in identifying common matches.

If you have a tree at Ancestry, you can easily download a copy and upload to GEDmatch. I wrote step-by-step instructions, here. Of course, you can upload any GEDCOM file from another source including your own desktop computer software.

You never know, using AutoSegment and AutoTree, you may just find common ancestors BETWEEN your matches that you aren’t aware of that might, just might, help you break down YOUR brick walls and find previously unknown ancestors.

AutoSegment tells you THAT you triangulate and exactly where. Now it’s up to you to figure out why.

Give AutoSegment at GEDmatch a try.

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Genetic Affairs – New AutoKinship Tool Predicts Relationships and Builds Genetic Trees

Genetic Affairs recently introduced a new tool – AutoKinship. Evert-Jan (EJ) Blom, the developer was kind enough to step through these results with me to assure that I’m explaining things correctly. Thanks EJ!

AutoKinship automatically predicts family trees and pathways that you may be related to your matches based on how they match you and each other. Not only is this important for genealogists trying to piece our family tree together, it’s indispensable for anyone searching for unknown ancestors, beginning with parents and walking right on up the tree for the closest several generations.

Right now, the automated AutoKinship tool is limited to 23andMe profiles, but will also work as a standalone tool where users can fill in the shared DNA information for their matches. MyHeritage, 23andMe, and GEDMatch provide centiMorgan information about how your matches also match each other. Here’s a tutorial for the standalone tool.

Unfortunately, Ancestry does not provide their customers with segment information, but fortunately, you can upload a copy of your Ancestry DNA file to MyHeritage, FamilyTreeDNA or GEDmatch, for free. You’ll find step-by-step instructions, here.

Automated AutoKinship Tool

After signing into to your Genetic Affairs account, assuming you have already set up your 23andMe profile at Genetic Affairs, click on “Run AutoKinship for 23andMe.”

I manage multiple profiles at 23andMe, so I need to click on “Profiles.”

Select the correct profile if you manage multiple kits at 23andMe.

You’ll see your various options that can be run for your 23andMe kit.

Select AutoKinship

If you select AutoKinship, you automatically receive an AutoCluster because AutoKinship is built on the AutoCluster functionality.

Make your selections. I recommend leaving these settings at the default, at least initially.

The default of 250 cM excludes your closest matches. You don’t want your closest matches because they will be members of too many clustered groups.

In my initial run, I made the mistake of changing the 50 cM lower threshold to 20 cM because I wanted more matches to be included. Unfortunately, the effect this had on my results was that my largest two clusters did not produce trees.

Hint: EJ states that the software tool works from the smallest cluster to the largest when producing trees. If you notice that your largest cluster, which is usually the first one displayed in the upper left hand corner (orange here), does not have associated trees, or some people are missing, that’s your clue that the AutoKinship ran out of server time to process and you need to raise either the minimum match threshold, in this case, 50 cM, or the minimum amount of DNA shared between your matches to each other, in this case, 10 cM.

You can also select between shared matches and triangulated groups. I selected shared matches, but I may well rerun this report with triangulated groups because that provides me with a great deal of even more useful information.

When you’re ready, click on the big green “you can’t miss it” Perform AutoCluster Analysis button.

Make a cup of coffee. Your report is processing. If your email doesn’t arrive, you can click on the little envelope in your Genetic Affairs profile and the report can be downloaded to your computer directly from that link.

Your Report Arrives!

You’ll receive a zip file in the email that you MUST SAVE TO YOUR COMPUTER to work correctly. You’ll see these files, but you can’t use them yet.

First, you MUST EXTRACT THE FILES from the zip file. My zip file displays the names of the file inside of the zipped file, but they are not extracted.

You must right click, as shown above, and then click on “Extract All” on a PC. Not sure what MAC users need to do but I think it autoextracts. If you click on some of the files in this article and they don’t load correctly, or say they aren’t present, that likely means:

  • You either forgot to save the file in the email to your computer
  • Or you failed to do the extract

The bottom two files are your normal AutoCluster visual html file and the same information in an excel file.

Click on the AutoCluster html file to activate.

Personally, I love watching the matches all fly into place in their clusters. This html file is going to be our home base, the file we’ll be operating from for all of the functions.

I have a total of 23 interrelated autoclusters. The question is, how are we all related to each other. You can read my article about AutoClusters and how they work here.

People who are members of more than one cluster are shown with those little grey squares signifying that they match people in two clusters, not just one cluster.

For example, one cluster might be my grandparents, but the second cluster might be my maternal great-great-grandfather. Membership in both clusters tells me that my matching DNA with those people in the second cluster probably descends from my great-great-grandfather. Some of the DNA matches in the first cluster assuredly also descend from that man, but some of them may descend from other related ancestors, like my maternal grandmother. It’s our job as genealogists to discern the connections, but the entire purpose of AutoKinship is to make that process much easier.

We are going to focus on the first few clusters to see what kinds of information Genetic Affairs can produce about these clusters. Notice that the first person in row 1 is related to the orange cluster, the green cluster, the purple and the brown clusters. That’s important information about that person, and also about the interrelationship of those clusters themselves and the ancestors they represent.

Remember, to be included in a grandparent cluster, that person’s DNA segment(s) must have descended from other ancestors, represented in other clusters. So you can expect one person to be found potentially in multiple clusters that serve to trace those common ancestors (and associated segments) back in time.

AutoKinship

The AutoKinship portion of this tool creates hypothetical trees based on relationships of you to each person in the cluster, and to the other cluster members to each other.

If you’re thinking triangulation, you’re right. I selected matches, not triangulated groups which is also an option. Some people do triangulate, but some people may match each other on different segments. Right now, it’s a jumble of hints, but we’ll sort some of this out.

If you scroll down in your html file, below your cluster, and below the explanation (which you should read,) you’ll see the AutoKinship verbiage.

I want to do a quick shout-out to Brit Nicholson, the statistician that works with EJ on probabilities of relationships for this tool and describes his methodology, here.

AutoKinship Table

You’ll see the AutoKinship Table that includes a link for each cluster that could be assembled into a potential tree.

Click on the cluster you wish to view.

In my case, clusters 1 through 5 are closely related to each other based on the common members in each cluster. I selected cluster 1.

Your most probable tree for that cluster will be displayed.

I’m fortunate that I recognized three of my third cousins. AutoKinship constructed a probable genetic pedigree, but I’ve overlayed what I know to be the correct pedigree.

With the exception of one person, this AutoKinship tree is accurate to the best of my knowledge. A slot for Elizabeth, the mother of William George Estes and the daughter of Joel is missing. I probably know why. I match two of my cousins with a higher than expected amount of DNA which means that I’m shown “closer” in genetic distance that I normally would be for that relationship level.

In one case, Charles and I share multiple ancestors. In the other case, I don’t know why I match Everett on so much more DNA than his brother Carl or our other cousin, Vianna. Regardless, I do.

In one other instance, there’s a half-relationship that throws a wrench into the tree. I know that, but it’s very difficult to factor half-relationships into tree building without prior knowledge.

If you continue to scroll down, you’ll see multiple options for trees for this cluster.

DNA Matrix

Below that, you’ll see a wonderful downloadable DNA matrix of how everyone in the cluster shares DNA with everyone else in the cluster.

At this point, exit from cluster one and return to your original cluster file that shows your cluster matrix.

Beneath the AutoKinship table, you’ll see AutoCluster Cluster Information.

AutoCluster Cluster Information

Click on any one of those people. I’m selecting Everett because I know how we are related.

Voila, a new cluster configuration forms.

I can see all of the people I match in common with Everett in each cluster. This tells me two things:

  • Which clusters are related to this line. In particular, the orange cluster, green, red, purple, brown, magenta and dark grey clusters. If you mouse over each cell in the cluster, more information is provided.
  • The little helix in each cell tells you that those two people triangulate with each other and the tester. How cool is that?!!

Note that you can display this cluster in 4 different ways.

Return again to your main autocluster page and scroll down once again.

This just might be my favorite part.

Chromosome Segments

You can import chromosome segment information into DNAPainter – instructions here.

What you’ll see next is the clusters painted on your chromosomes. I love this!!!

Of course, Genetic Affairs can’t tell you which side is maternal and which is paternal. You’ll need to do that yourself after you import into DNAPainter.

Just beneath this painting, you’ll see a chart titled Chromosome segment statistics per AutoCluster cluster.

I’m only showing the first couple as an example.

Click on one of links. I’m selecting cluster 1.

Cluster 1 has painted portions of each chromosome, but I’m only displaying chromosomes 1-7 here.

Following the painting is a visual display of each overlap region by cluster, by overlapping segment on each chromosome.

You can clearly see where these segments overlap with each other!

Surname Enrichment

If you select the surname enrichment option, you’ll receive two additional features in your report.

Please note that I ran this option separately at a different time, so the cluster members and clusters themselves do not necessarily correlate with the examples above.

The Enriched Surname section of your report shows surnames in common found between the matches in each specific cluster.

Keep in mind, this does NOT just mean surnames in common with YOUR surname list, assuming you’ve entered your surnames at 23andMe. (If you haven’t please do so now.) 23andMe does not support user trees, so your entered surnames are all that can be utilized when comparing information from your matches.

These are surnames that are found more than once among your matches. I’ve framed the ones in red that I recognize as being found in my tree, and I’ve framed the ones in black that I recognize as being “married in.” In other words, some people may descend through children of my ancestors who married people with that black bracketed surname.

I can tell you immediately, based on these surnames, that the first cluster is the cluster formed around my great-great-grandparents, Joel Vannoy and his wife, Phebe Crumley.

Cluster 6 is less evident, but Anderson might be connected to the Vannoy family. I’ll need to view the common matches in that cluster at 23andMe and look for additional clues.

Cluster 9 is immediately evident too. Ferverda is Hiram Ferverda, my great-grandfather and Eva Miller is his wife.

Cluster 10 is probably the Miller line as well. Indiana is a location in this case, not a surname.

Click on “Detailed Surname Table” for more information, as shown below.

Each group of people that shares any surname is shown in a table together. In this case, these three people, who I happen to know are brothers, all share these surnames. The surnames they also share with me are shown with red boxes. The other surnames are shared only with each other and no one else in the cluster. I know they aren’t shared with me because I know my tree.

While your initial reaction may be that this isn’t terribly useful, it is actually a HUGE gift. Especially if you find a cluster you aren’t familiar with.

Mystery Cluster

A mystery cluster is an opportunity to break down a brick wall. This report tells you which people to view on your match list who share that surname. My first step is to use that list and see who I match in common with each person at 23andMe.

My relatives in common with my Cluster 10 matches include my close Ferverda cousins who descend from our common Miller ancestor, plus a few Miller cousins. This confirms that this cluster does indeed originate in the Miller line.

Not everyone in that cluster shares the surname Miller. That might be a good thing.

I have a long-standing brick wall with Magdalena (surname unknown) who was married to Philip Jacob Miller, my 5-times great-grandparents. My cousins through that couple, at my same generation, would be about 6th cousins.

These matches are matching me at the approximate 4th cousin level or more distantly, so it’s possible that at least some of these matches COULD be through Magdalena’s family. In that case, I certainly would not recognize the common surnames. Therefore, it’s imperative that I chase these leads. I can also adjust the matching threshold to obtain more matches, hopefully, in this cluster, and run the report again.

Are you in love with Autokinship and its associated features yet? I am!

Summary

Wow is all I can say. There’s enough in this one report to keep me busy for days, especially since 23andMe does not support a tree function in the traditional genealogical sense.

I have several matches that I have absolutely no idea how they are related to me. This helps a great deal and allows to me systematically approach tree-building or identifying ancestors.

You can see if 23andMe has predicted these relationships in the same way, but other than messaging your matches, or finding them at another vendor who does support a tree, there’s no way to know if either 23andMe’s autogenerated tree or the Genetic Affairs trees are accurate.

What Genetic Affairs provides that 23andMe does not is composite information in one place – as a group in a cluster. You don’t have to figure out who matches whom one by one and create your own matrix. (Yes, I used to do that.)

You can also import the Genetic Affairs information into DNAPainter to make further use of these segments. I’ve written about using DNAPainter, here.

Once you’ve identified how one person in any cluster connects, you’ve found your lever to unlock the identity of the ancestors whose DNA is represented in that particular cluster – and an important clue/link to associated clusters as well.

If you don’t recognize these cousins at 23andMe, look for common surnames on your DNA Relatives match list, or see if a known close relative on your maternal or paternal side matches these people found in a cluster. Click on each match at 23andMe to see if they have provided notes, surnames, locations or even a link to a tree at another vendor.

Don’t forget, you can also select the “Based on Triangulated Groups” option instead of the “Based on Shared Matches” option initially.

Run A Report

If you have tested at 23andMe, give the Genetic Affairs AutoKinship report a try.

Is it accurate for you? Have you gained insight? Identified how people are related to you? Are there any surprises?

Do you have a mystery cluster? I hope so, because an answer just might be hiding there.

If you’d like to read more about Genetic Affairs tools, click here for my free repository of Genetic Affairs articles.

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A Triangulation Checklist Born From the Question; “Why NOT Use Close Relatives for Triangulation?”

One of my readers asked why we don’t use close relatives for triangulation.

This is a great question because not using close relatives for triangulation seems counter-intuitive.

I used to ask my kids and eventually my students and customers if they wanted the quick short answer or the longer educational answer.

The short answer is “because close relatives are too close to reliably form the third leg of the triangle.” Since you share so much DNA with close relatives, someone matching you who is identical by chance can also match them for exactly the same reason.

If you trust me and you’re good with that answer, wonderful. But I hope you’ll keep reading because there’s so much to consider, not to mention a few gotchas. I’ll share my methodology, techniques, and workarounds.

We’ll also discuss absolutely wonderful ways to utilize close relatives in the genetic genealogical process – just not for triangulation.

At the end of this article, I’ve provided a working triangulation checklist for you to use when evaluating your matches.

Let’s go!

The Step-by-Step Educational Answer😊

Some people see “evidence” they believe conflicts with the concept that you should not use close relatives for triangulation. I understand that, because I’ve gone down that rathole too, so I’m providing the “educational answer” that explains exactly WHY you should not use close relatives for triangulation – and what you should do.

Of course, we need to answer the question, “Who actually are close relatives?”

I’ll explain the best ways to best utilize close relatives in genetic genealogy, and why some matches are deceptive.

You’ll need to understand the underpinnings of DNA inheritance and also of how the different vendors handle DNA matching behind the scenes.

The purpose of autosomal DNA triangulation is to confirm that a segment is passed down from a particular ancestor to you and a specific set of your matches.

Triangulation, of course, implies 3, so at least three people must all match each other on a reasonably sized portion of the same DNA segment for triangulation to occur.

Matching just one person only provides you with one path to that common ancestor. It’s possible that you match that person due to a different ancestor that you aren’t aware of, or due to chance recombination of DNA.

It’s possible that your or your match inherited part of that DNA from your maternal side and part from your paternal side, meaning that you are matching that other person’s DNA by chance.

I wrote about identical by descent (IBD), which is an accurate genealogically meaningful match, and identical by chance (IBC) which is a false match, in the article Concepts – Identical by…Descent, State, Population and Chance.

I really want you to understand why close relatives really shouldn’t be used for triangulation, and HOW close relative matches should be used, so we’re going to discuss all of the factors that affect and influence this topic – both the obvious and little-understood.

  • Legitimate Matches
  • Inheritance and Triangulation
  • Parental Cross-Matching
  • Parental Phasing
  • Automatic Phasing at FamilyTreeDNA
  • Parental Phasing Caveats
  • Pedigree Collapse
  • Endogamy
  • How Many Identical-by-Chance Matches Will I Have?
  • DNA Doesn’t Skip Generations (Seriously, It Doesn’t)
  • Your Parents Have DNA That You Don’t (And How to Use It)
  • No DNA Match Doesn’t Mean You’re Not Related
  • Imputation
  • Ancestry Issues and Workarounds
  • Testing Close Relatives is VERY Useful – Just Not for Triangulation
  • Triangulated Matches
  • Building Triangulation Evidence – Ingredients and a Recipe
  • Aunts/Uncles
  • Siblings
  • How False Positives Work and How to Avoid Them
  • Distant Cousins Are Best for Triangulation & Here’s Why
  • Where Are We? A Triangulation Checklist for You!
  • The Bottom Line

Don’t worry, these sections are logical and concise. I considered making this into multiple articles, but I really want it in one place for you. I’ve created lots of graphics with examples to help out.

Let’s start by dispelling a myth.

DNA Doesn’t Skip Generations!

Recently, someone emailed to let me know that they had “stopped listening to me” in a presentation when I said that if a match did not also match one of your parents, it was a false match. That person informed me that they had worked on their tree for three years at Ancestry and they have “proof” of DNA skipping generations.

Nope, sorry. That really doesn’t happen, but there are circumstances when a person who doesn’t understand either how DNA works, or how the vendor they are using presents DNA results could misunderstand or misinterpret the results.

You can watch my presentation, RootsTech session, DNA Triangulation: What, Why and How, for free here. I’m thrilled that this session is now being used in courses at two different universities.

DNA really doesn’t skip generations. You CANNOT inherit DNA that your parents didn’t have.

Full stop.

Your children cannot inherit DNA from you that you don’t carry. If you don’t have that DNA, your children and their descendants can’t have it either, at least not from you. They of course do inherit DNA from their other parent.

I think historically, the “skipping generations” commentary was connected to traits. For example, Susie has dimples (or whatever) and so did her maternal grandmother, but her mother did not, so Susie’s dimples were said to have “skipped a generation.” Of course, we don’t know anything about Susie’s other grandparents, if Susie’s parents share ancestors, recessive/dominant genes or even how many genetic locations are involved with the inheritance of “dimples,” but I digress.

DNA skipping generations is a fallacy.

You cannot legitimately match someone that your parent does not, at least not through that parent’s side of the tree.

But here’s the caveat. You can’t match someone one of your parents doesn’t with the rare exception of:

  • Relatively recent pedigree collapse that occurs when you have the same ancestors on both sides of your tree, meaning your parents are related, AND
  • The process of recombination just happened to split and recombine a segment of DNA in segments too small for your match to match your parents individually, but large enough when recombined to match you.

We’ll talk about that more in a minute.

However, the person working with Ancestry trees can’t make this determination because Ancestry doesn’t provide segment information. Ancestry also handles DNA differently than other vendors, which we’ll also discuss shortly.

We’ll review all of this, but let’s start at the beginning and explain how to determine if our matches are legitimate, or not.

Legitimate Matches

Legitimate matches occur when the DNA of your ancestor is passed from that ancestor to their descendants, and eventually to you and a match in an unbroken pathway.

Unbroken means that every ancestor between you and that ancestor carried and then passed on the segment of the ancestor’s DNA that you carry today. The same is true for your match who carries the same segment of DNA from your common ancestor.

False positive matches occur when the DNA of a male and female combine randomly to look like a legitimate match to someone else.

Thankfully, there are ways to tell the difference.

Inheritance and Triangulation

Remember, you inherit two copies of each of your chromosomes 1-22, one copy from your mother and one from your father. You inherit half of the DNA that each parent carries, but it’s mixed together in you so the labs can’t readily tell which nucleotide, A, C, T, or G you received from which parent. I’m showing your maternal and paternal DNA in the graphic below, stacked neatly together in a column – but in reality, it could be AC in one position and CA in the next.

For matching all that matters is the nucleotide that matches your match is present in one of those two locations. In this case, A for your mother’s side and C for your father’s side. If you’re interested, you can read more about that in the article, Hit a Genealogy Home Run Using Your Double-Sided Two-Faced Chromosomes While Avoiding Imposters.

You can see in this example that you inherited all As from your Mom and all Cs from your Dad.

  • A legitimate maternal match would match you on all As on this particular example segment.
  • A legitimate paternal match would match you on all Cs on this particular segment.
  • A false positive match will match you on some random combination of As and Cs that make it look like they match you legitimately, but they don’t.
  • A false positive match will NOT match either your mother or your father.

To be very clear, technically a false positive match DOES match your DNA – but they don’t match your DNA because you share a common ancestor with your match. They match you because random recombination on their side causes you to match each other by chance.

In other words, if part of your DNA came from your Mom’s side and part from your Dad’s but it randomly fell in the correct positional order, you’d still match someone whose DNA was from only their mother or father’s side. That’s exactly the situation shown above and below.

Looking at our example again, it’s evident that your identical by chance (IBC) match’s A locations (1, 3, 5, 7 & 9) will match your Mom. C locations (2, 4, 6 8, & 10) will match your Dad, but the nonmatching segments interleaved in-between that match alternating parents will prevent your match from matching either of your parents. In other words, out of 10 contiguous locations in our example, your IBC match has 5 As alternated with 5 Cs, so they won’t match either of your parents who have 10 As or 10 Cs in a row.

This recombination effect can work in either direction. Either or both matching people’s DNA could be randomly mixed causing them to match each other, but not their parents.

Regardless of whose DNA is zigzagging back and forth between maternal and paternal, the match is not genealogical and does not confirm a common ancestor.

This is exactly why triangulation works and is crucial.

If you legitimately match a third person, shown below, on your maternal side, they will match you, your first legitimate maternal match, and your Mom because they carry all As. But they WON’T match the person who is matching you because they are identical by chance, shown in grey below.

The only person your identical by chance match matches in this group is you because they match you because of the chance recombination of parental DNA.

That third person WILL also match all other legitimate maternal matches on this segment.

In the graphic above, we see that while the grey identical by chance person matches you because of the random combination of As from your mother and Cs from your father, your legitimate maternal matches won’t match your identical by chance match.

This is the first step in identifying false matches.

Parental Cross-Matching

Removing the identical by chance match, and adding in the parents of your legitimate maternal match, we see that your maternal match, above, matches you because you both have all As inherited from one parent, not from a combination of both parents.

We know that because we can see the DNA of both parents of both matches in this example.

The ideal situation occurs when two people match and they have both had their parents tested. We need to see if each person matches the other person’s parents.

We can see that you do NOT match your match’s father and your match does NOT match your father.

You do match your match’s mother and your match does match your mother. I refer to this as Parental Cross-matching.

Your legitimate maternal matches will also match each other and your mother if she is available for testing.

All the people in yellow match each other, while the two parents in gray do not match any of your matches. An entire group of legitimate maternal matches on this segment, no matter how many, will all match each other.

If another person matches you and the other yellow people, you’ll still need to see if you match their parents, because if not, that means they are matching you on all As because their two parents DNA combined just happened, by chance, to contribute an A in all of those positions.

In this last example, your new match, in green, matches you, your legitimate match and both of your mothers, BUT, none of the four yellow people match either of the new match’s parents. You can see that the new green match inherited their As from the DNA of their mother and father both, randomly zigzagging back and forth.

The four yellow matches phase parentally as we just proved with cross matching to parents. The new match at first glance appears to be a legitimate match because they match all of the yellow people – but they aren’t because the yellow people don’t match the green person’s parents.

To tell the difference between legitimate matches and identical by chance matches, you need two things, in order.

  • Parental matching known as parental phasing along with parental cross-matching, if possible, AND
  • Legitimate identical by descent (IBD) triangulated matches

If you have the ability to perform parental matching, called phasing, that’s the easiest first step in eliminating identical by chance matches. However, few match pairs will have parents for everyone. You can use triangulation without parental phasing if parents aren’t available.

Let’s talk about both, including when and how close relatives can and cannot be used.

Parental Phasing

The technique of confirming your match to be legitimate by your match also matching one of your parents is called parental phasing.

If we have the parents of both people in a match pair available for matching, we can easily tell if the match does NOT match either parent. That’s Parental Cross Matching. If either match does NOT match one of the other person’s parents, the match is identical by chance, also known as a false positive.

See how easy that was!

If you, for example, is the only person in your match pair to have parents available, then you can parentally phase the match on your side if your match matches your parents. However, because your match’s parents are unavailable, your match to them cannon tbe verified as legitimate on their side. So you are not phased to their parents.

If you only have one of your parents available for matching, and your match does not match that parent, you CANNOT presume that because your match does NOT match that parent, the match is a legitimate match for the other, missing, parent.

There are four possible match conditions:

  • Maternal match
  • Paternal match
  • Matches neither parent which means the match is identical by chance meaning a false positive
  • Matches both parents in the case of pedigree collapse or endogamy

If two matching people do match one parent of both matches (parental cross-matching), then the match is legitimate. In other words, if we match, I need to match one of your parents and you need to match one of mine.

It’s important to compare your matches’ DNA to generationally older direct family members such as parents or grandparents, if that’s possible. If your grandparents are available, it’s possible to phase your matches back another generation.

Automatic Phasing at FamilyTreeDNA

FamilyTreeDNA automatically phases your matches to your parents if you test that parent, create or upload a GEDCOM file, and link your test and theirs to your tree in the proper places.

FamilyTreeDNA‘s Family Matching assigns or “buckets” your matches maternally and paternally. Matches are assigned as maternal or paternal matches if one or both parents have tested.

Additionally, FamilyTreeDNA uses triangulated matches from other linked relatives within your tree even if your parents have not tested. If you don’t have your parents, the more people you identify and link to your tree in the proper place, the more people will be assigned to maternal and paternal buckets. FamilyTreeDNA is the only vendor that does this. I wrote about this process in the article, Triangulation in Action at Family Tree DNA.

Parental Phasing Caveats

There are very rare instances where parental phasing may be technically accurate, but not genealogically relevant. By this, I mean that a parent may actually match one of your matches due to endogamy or a population level match, even if it’s considered a false positive because it’s not relevant in a genealogical timeframe.

Conversely, a parent may not match when the segment is actually legitimate, but it’s quite rare and only when pedigree collapse has occurred in a very specific set of circumstances where both parents share a common ancestor.

Let’s take a look at that.

Pedigree Collapse

It’s not terribly uncommon in the not-too-distant past to find first cousins marrying each other, especially in rather closely-knit religious communities. I encounter this in Brethren, Mennonite and Amish families often where the community was small and out-marrying was frowned upon and highly discouraged. These families and sometimes entire church congregations migrated cross-country together for generations.

When pedigree collapse is present, meaning the mother and father share a common ancestor not far in the past, it is possible to inherit half of one segment from Mom and the other half from Dad where those halves originated with the same ancestral couple.

For example, let’s say the matching segment between you and your match is 12 cM in length, shown below. You inherited the blue segment from your Dad and the neighboring peach segment from Mom – shown just below the segment numbers. You received 6 cM from both parents.

Another person’s DNA does match you, shown in the bottom row, but they are not shown on the DNA match list of either of your parents. That’s because the DNA segments of the parents just happened to recombine in 6 cM pieces, respectively, which is below the 7 cM matching threshold of the vendor in this example.

If the person matched you at 12 cM where you inherited 8 cM from one parent and 4 from the other, that person would show on one parent’s match list, but not the other. They would not be on the parent’s match list who contributed only 4 cM simply because the DNA divided and recombined in that manner. They would match you on a longer segment than they match your parent at 8 cM which you might notice as “odd.”

Let’s look at another example.

click to enlarge image

If the matching segment is 20 cM, the person will match you and both of your parents on different pieces of the same segment, given that both segments are above 7 cM. In this case, your match who matches you at 20 cM will match each of your parents at 10 cM.

You would be able to tell that the end location of Dad’s segment is the same as the start location of Mom’s segment.

This is NOT common and is NOT the “go to” answer when you think someone “should” match your parent and does not. It may be worth considering in known pedigree collapse situations.

You can see why someone observing this phenomenon could “presume” that DNA skipped a generation because the person matches you on segments where they don’t match your parent. But DNA didn’t skip anything at all. This circumstance was caused by a combination of pedigree collapse, random division of DNA, then random recombination in the same location where that same DNA segment was divided earlier. Clearly, this sequence of events is not something that happens often.

If you’ve uploaded your DNA to GEDmatch, you can select the “Are your parents related?” function which scans your DNA file for runs of homozygosity (ROH) where your DNA is exactly the same in both parental locations for a significant distance. This suggests that because you inherited the exact same sequence from both parents, that your parents share an ancestor.

If your parents didn’t inherit the same segment of DNA from both parents, or the segment is too short, then they won’t show as “being related,” even if they do share a common ancestor.

Now, let’s look at the opposite situation. Parental phasing and ROH sometimes do occur when common ancestors are far back in time and the match is not genealogically relevant.

Endogamy

I often see non-genealogical matching occur when dealing with endogamy. Endogamy occurs when an entire population has been isolated genetically for a long time. In this circumstance, a substantial part of the population shares common DNA segments because there were few original population founders. Much of the present-day population carries that same DNA. Many people within that population would match on that segment. Think about the Jewish community and indigenous Americans.

Consider our original example, but this time where much of the endogamous population carries all As in these positions because one of the original founders carried that nucleotide sequence. Many people would match lots of other people regardless of whether they are a close relative or share a distant ancestor.

People with endogamous lines do share relatives, but that matching DNA segment originated in ancestors much further back in time. When dealing with endogamy, I use parental phasing as a first step, if possible, then focus on larger matches, generally 20 cM or greater. Smaller matches either aren’t relevant or you often can’t tell if/how they are.

At FamilyTreeDNA, people with endogamy will find many people bucketed on the “Both” tab meaning they triangulate with people linked on both sides of the tester’s tree.

An example of a Jewish person’s bucketed matches based on triangulation with relatives linked in their tree is shown above.

Your siblings, their children, and your children will be related on both your mother’s and father’s sides, but other people typically won’t be unless you have experienced either pedigree collapse where you are related both maternally and paternally through the same ancestors or you descend from an endogamous population.

How Many Identical-by-Chance Matches Will I Have?

If you have both parents available to test, and you’re not dealing with either pedigree collapse or endogamy, you’ll likely find that about 15-20% of your matches don’t match your parents on the same segment and are identical by chance.

With endogamy, you’ll have MANY more matches on your endogamous lines and you’ll have some irrelevant matches, often referred to as “false positive” matches even though they technically aren’t, even using parental phasing.

Your Parents Have DNA That You Don’t

Sometimes people are confused when reviewing their matches and their parent’s match to the same person, especially when they match someone and their parent matches them on a different or an additional segment.

If you match someone on a specific segment and your parents do not, that’s a false positive FOR THAT SEGMENT. Every segment has its own individual history and should be evaluated individually. You can match someone on two segments, one from each parent. Or three segments, one from each parent and one that’s identical by chance. Don’t assume.

Often, your match will match both you and your parent on the same segment – which is a legitimate parentally phased match.

But what if your match matches your parent on a different segment where they don’t match you? That’s a false positive match for you.

Keep in mind that it is possible for one of your matches to match your parent on a separate or an additional segment that IS legitimate. You simply didn’t inherit that particular segment from your parent.

That’s NOT the same situation as someone matching you that does NOT match one of your parents on the same segment – which is an identical by chance or false match.

Your parent having a match that does not match you is the reverse situation.

I have several situations where I match someone on one segment, and they match my parent on the same segment. Additionally, that person matches my parent on another segment that I did NOT inherit from that parent. That’s perfectly normal.

Remember, you only inherit half of your parent’s DNA, so you literally did NOT inherit the other half of their DNA. Your mother, for example, should have twice as many matches as you on her side because roughly half of her matches won’t match you.

That’s exactly why testing your parents and close family members is so critical. Their matches are as valid and relevant to your genealogy as your own. The same is true for other relatives, such as aunts and uncles with whom you share ALL of the same ancestors.

You need to work with your family member’s matches that you don’t share.

No DNA Match Doesn’t Mean You’re Not Related

Some people think that not matching someone on a DNA test is equivalent to saying they aren’t related. Not sharing DNA doesn’t mean you’re not related.

People are often disappointed when they don’t match someone they think they should and interpret that to mean that the testing company is telling them they “aren’t related.” They are upset and take issue with this characterization. But that’s not what it means.

Let’s analyze this a bit further.

First, not sharing DNA with a second cousin once removed (2C1R) or more distant does NOT mean you’re NOT related to that person. It simply means you don’t share any measurable DNA ABOVE THE VENDOR THRESHOLD.

All known second cousins match, but about 10% of third cousins don’t match, and so forth on up the line with each generation further back in time having fewer cousins that match each other.

If you have tested close relatives, check to see if that cousin matches your relatives.

Second, it’s possible to match through the “other” or unexpected parent. I certainly didn’t think this would be the case in my family, because my father is from Appalachia and my mother’s family is primarily from the Netherlands, Germany, Canada, and New England. But I was wrong.

All it took was one German son that settled in Appalachia, and voila, a match through my mother that I surely thought should have been through my father’s side. I have my mother’s DNA and sure enough, my match that I thought should be on my father’s side matches Mom on the same segment where they match me, along with several triangulated matches. Further research confirmed why.

I’ve also encountered situations where I legitimately match someone on both my mother’s and father’s side, on different segments.

Third, imputation can be important for people who don’t match and think they should. Imputation can also cause matching segment length to be overreported.

Ok, so what’s imputation and why do I care?

Imputation

Every DNA vendor today has to use some type of imputation.

Let me explain, in general, what imputation is and why vendors use it.

Over the years, DNA processing vendors who sell DNA chips to testing companies have changed their DNA chips pretty substantially. While genealogical autosomal tests test about 700,000 DNA locations, plus or minus, those locations have changed over time. Today, some of these chips only have 100,000 or so chip locations in common with chips either currently or previously utilized by other vendors.

The vendors who do NOT accept uploads, such as 23andMe or Ancestry, have to develop methods to make their newest customers on their DNA processing vendor’s latest chip compatible with their first customer who was tested on their oldest chip – and all iterations in-between.

Vendors who do accept transfers/uploads from other vendors have to equalize any number of vendors’ chips when their customers upload those files.

Imputation is the scientific way to achieve this cross-platform functionality and has been widely used in the industry since 2017.

Imputation, in essence, fills in the blanks between tested locations with the “most likely” DNA found in the human population based on what’s surrounding the blank location.

Think of the word C_T. There are a limited number of letters and words that are candidates for C_T. If you use the word in a sentence, your odds of accuracy increase dramatically. Think of a genetic string of nucleotides as a sentence.

Imputation can be incorrect and can cause both false positive and false negative matches.

For the most part, imputation does not affect close family matches as much as more distant matches. In other words, imputation is NOT going to cause close family members not to match.

Imputation may cause more distant family members not to match, or to have a false positive match when imputation is incorrect.

Imputation is actually MUCH less problematic than I initially expected.

The most likely effect of imputation is to cause a match to be just above or below the vendor threshold.

How can we minimize the effects of imputation?

  • Generally, the best result will be achieved if both people test at the same vendor where their DNA is processed on the same chip and less imputation is required.
  • Upload the results of both people to both MyHeritage and FamilyTreeDNA. If your match results are generally consistent at those vendors, imputation is not a factor.
  • GEDmatch does not use imputation but attempts to overcome files with low overlapping regions by allowing larger mismatch areas. I find their matches to be less accurate than at the various vendors.

Additionally, Ancestry has a few complicating factors.

Ancestry Issues

AncestryDNA is different in three ways.

  • Ancestry doesn’t provide segment information so it’s impossible to triangulate or identify the segment or chromosome where people match. There is no chromosome browser or triangulation tool.
  • Ancestry down-weights and removes some segments in areas where they feel that people are “too matchy.” You can read Ancestry’s white papers here and here.

These “personal pileup regions,” as they are known, can be important genealogically. In my case, these are my mother’s Acadian ancestors. Yes, this is an endogamous population and also suffers from pedigree collapse, but since this is only one of my mother’s great-grandparents, this match information is useful and should not be removed.

  • Ancestry doesn’t show matches in common if the shared segments are less than 20cM. Therefore, you may not see someone on a shared match list with a relative when they actually are a shared match.

If two people both match a third person on less than a 20 cM segment at Ancestry, the third person won’t appear on the other person’s shared match list. So, if I match John Doe on 19 cM of DNA, and I looked at the shared matches with my Dad, John Doe does NOT appear on the shared match list of me and my Dad – even though he is a match to both of us at 19 cM.

The only way to determine if John Doe is a shared match is to check my Dad’s and my match list individually, which means Dad and I will need to individually search for John Doe.

Caveat here – Ancestry’s search sometimes does not work correctly.

Might someone who doesn’t understand that the shared match list doesn’t show everyone who shares DNA with both people presume that the ancestral DNA of that ancestor “skipped a generation” because John Doe matches me with a known ancestor, and not Dad on our shared match list? I mean, wouldn’t you think that a shared match would be shown on a tab labeled “Shared Matches,” especially since there is no disclaimer?

Yes, people can be forgiven for believing that somehow DNA “skipped” a generation in this circumstance, especially if they are relatively inexperienced and they don’t understand Ancestry’s anomalies or know that they need to or how to search for matches individually.

Even if John Doe does match me and Dad both, we still need to confirm that it’s on the same segment AND it’s a legitimate match, not IBC. You can’t perform either of these functions at Ancestry, but you can elsewhere.

Ancestry WorkArounds

To obtain this functionality, people can upload their DNA files for free to both FamilyTreeDNA and MyHeritage, companies that do provide full shared DNA reporting (in common with) lists of ALL matches and do provide segment information with chromosome browsers. Furthermore, both provide triangulation in different ways.

Matching is free, but an inexpensive unlock is required at both vendors to access advanced tools such as Family Matching (bucketing) and triangulation at Family Tree DNA and phasing/triangulation at MyHeritage.

I wrote about Triangulation in Action at FamilyTreeDNA, here.

MyHeritage actually brackets triangulated segments for customers on their chromosome browser, including parents, so you get triangulation and parental phasing at the same time if you and your parent have both tested or uploaded your DNA file to MyHeritage. You can upload, for free, here.

In this example, my mother is matching to me in red on the entire length of chromosome 18, of course, and three other maternal cousins triangulate with me and mother inside the bracketed portion of chromosome 18. Please note that if any one of the people included in the chromosome browser comparison do not triangulate, no bracket is drawn around any others who do triangulate. It’s all or nothing. I remove people one by one to see if people triangulate – or build one by one with my mother included.

I wrote about Triangulation in Action at MyHeritage, here.

People can also upload to GEDmatch, a third-party site. While GEDmatch is less reliable for matching, you can adjust your search thresholds which you cannot do at other vendors. I don’t recommend routinely working below 7 cM. I occasionally use GEDmatch to see if a pedigree collapse segment has recombined below another vendor’s segment matching threshold.

Do NOT check the box to prevent hard breaks when selecting the One-to-One comparison. Checking that box allows GEDmatch to combine smaller matching segments into mega-segments for matching.

I wrote about Triangulation in Action at GEDmatch, here.

Transferring/Uploading Your DNA 

If you want to transfer your DNA to one of these vendors, you must download the DNA file from one vendor and upload it to another. That process does NOT remove your DNA file from the vendor where you tested, unless you select that option entirely separately.

I wrote full step-by-step transfer/upload instructions for each vendor, here.

Testing Close Relatives Is VERY Useful – Just Not for Triangulation

Of course, your best bet if you don’t have your parents available to test is to test as many of your grandparents, great-aunts/uncles, aunts, and uncles as possible. Test your siblings as well, because they will have inherited some of the same and some different segments of DNA from your parents – which means they carry different pieces of your ancestors’ DNA.

Just because close relatives don’t make good triangulation candidates doesn’t mean they aren’t valuable. Close relatives are golden because when they DO share a match with you, you know where to start looking for a common ancestor, even if your relative matches that person on a different segment than you do.

Close relatives are also important because they will share pieces of your common ancestor’s DNA that you don’t. Their matches can unlock the answers to your genealogy questions.

Ok, back to triangulation.

Triangulated Matches

A triangulated match is, of course, when three people all descended from a common ancestor and match each other on the same segment of DNA.

That means all three people’s DNA matches each other on that same segment, confirming that the match is not by chance, and that segment did descend from a common ancestor or ancestral couple.

But, is this always true? You’re going to hate this answer…

“It depends.”

You knew that was coming, didn’t you! 😊

It depends on the circumstances and relationships of the three people involved.

  • One of those three people can match the other two by chance, not by descent, especially if two of those people are close relatives to each other.
  • Identical by chance means that one of you didn’t inherit that DNA from one single parent. That zigzag phenomenon.
  • Furthermore, triangulated DNA is only valid as far back as the closest common ancestor of any two of the three people.

Let’s explore some examples.

Building Triangulation Evidence – Ingredients and a Recipe

The strongest case of triangulation is when:

  • You and at least two additional cousins match on the same segment AND
  • Descend through different children of the common ancestral couple

Let’s look at a valid triangulated match.

In this first example, the magenta segment of DNA is at least partially shared by four of the six cousins and triangulates to their common great-grandfather. Let’s say that these cousins then match with two other people descended from different children of their great-great-great-grandparents on this same segment. Then the entire triangulation group will have confirmed that segment’s origin and push the descent of that segment back another two generations.

These people all coalesce into one line with their common great-grandparents.

I’m only showing 3 generations in this triangulated match, but the concept is the same no matter how many generations you reach back in time. Although, over time, segments inherited from any specific ancestor become smaller and smaller until they are no longer passed to the next generation.

In this pedigree chart, we’re only tracking the magenta DNA which is passed generation to generation in descendants.

Eventually, of course, those segments become smaller and indistinguishable as they either aren’t passed on at all or drop below vendor matching thresholds.

This chart shows the average amount of DNA you would carry from each generational ancestor. You inherit half of each parent’s DNA, but back further than that, you don’t receive exactly half of any ancestor’s DNA in any generation. Larger segments are generally cut in two and passed on partially, but smaller segments are often either passed on whole or not at all.

On average, you’ll carry 7 cM of your eight-times-great-grandparents. In reality, you may carry more or you may not carry any – and you are unlikely to carry the same segment as any random other descendants but we know it happens and you’ll find them if enough (or the right) descendants test.

Putting this another way, if you divide all of your approximate 7000 cM of DNA into 7 cM segments of equal length – you’ll have 1000 7 cM segments. So will every other descendant of your eight-times-great-grandparent. You can see how small the chances are of you both inheriting that same exact 7 cM segment through ten inheritance/transmission events, each. Yet it does happen.

I have several triangulated matches with descendants of Charles Dodson and his wife, Anne through multiple of their 9 (or so) children, ten generations back in my tree. Those triangulated matches range from 7-38 cM. It’s possible that those three largest matches at 38 cM could be related through multiple ancestors because we all have holes in our trees – including Anne’s surname.

Click to enlarge image

It helps immensely that Charles Dodson had several children who were quite prolific as well.

Of course, the further back in time, the more “proof” is necessary to eliminate other unknown common ancestors. This is exactly why matching through different children is important for triangulation and ancestor confirmation.

The method we use to confirm the common ancestor is that all of the descendants who match the tester on the same segment all also match each other. This greatly reduces the chances that these people are matching by chance. The more people in the triangulation group, the stronger the evidence. Of course, parental phasing or cross-matching, where available is an added confirmation bonus.

In our magenta inheritance example, we saw that three of the males and one of the females from three different descendants of the great-grandparents all carry at least a portion of that magenta segment of great-grandpa’s DNA.

Now, let’s take a look at a different scenario.

Why can’t siblings or close relatives be used as two of the three people needed for triangulation?

Aunts and Uncles

We know that the best way to determine if a match is valid is by parental phasing – your match also matching to one of your parents.

If both parents aren’t available, looking for close family matches in common with your match is the next hint that genealogists seek.

Let’s say that you and your match both match your aunt or uncle in common or their children.

You and your aunts or uncles matching DNA only pushes your common ancestor back to your grandparents.

At that point, your match is in essence matching to a segment that belongs to your grandparents. Your matches’ DNA, or your grandparents’ DNA could have randomly recombined and you and your aunt/cousins could be matching that third person by chance.

Ok, then, what about siblings?

Siblings

The most recent common ancestor (MRCA) of you and someone who also matches your sibling is your parents. Therefore, you and your sibling actually only count as one “person” in this scenario. In essence, it’s the DNA of your parent(s) that is matching that third person, so it’s not true triangulation. It’s the same situation as above with aunts/uncles, except the common ancestor is closer than your grandparents.

The DNA of your parents could have recombined in both siblings to look like a match to your match’s family. Or vice versa. Remember Parental Cross-Matching.

If you and a sibling inherited EXACTLY the same segment of your Mom’s and Dad’s DNA, and you match someone by chance – that person will match your sibling by chance as well.

In this example, you can see that both siblings 1 and 2 inherited the exact same segments of DNA at the same locations from both of their parents.

Of course, they also inherited segments at different locations that we’re not looking at that won’t match exactly between siblings, unless they are identical twins. But in this case, the inherited segments of both siblings will match someone whose DNA randomly combined with green or magenta dots in these positions to match a cross-section of both parents.

How False Positives Work and How to Avoid Them

We saw in our first example, displayed again above, what a valid triangulated match looks like. Now let’s expand this view and take a look more specifically at how false positive matches occur.

On the left-hand (blue) side of this graphic, we see four siblings that descend through their father from Great-grandpa who contributed that large magenta segment of DNA. That segment becomes reduced in descendants in subsequent generations.

In downstream generations, we can see gold, white and green segments being added to the DNA inherited by the four children from their ancestor’s spouses. Dad’s DNA is shown on the left side of each child, and Mom’s on the right.

  • Blue Children 1 and 2 inherited the same segments of DNA from Mom and Dad. Magenta from Dad and green from Mom.
  • Blue Child 3 inherited two magenta segments from Dad in positions 1 and 2 and one gold segment from Dad in position 3. They inherited all white segments from Mom.
  • Blue Child 4 inherited all gold segments from Dad and all white segments from Mom.

The family on the blue left-hand side is NOT related to the pink family shown at right. That’s important to remember.

I’ve intentionally constructed this graphic so that you can see several identical by chance (IBC) matches.

Child 5, the first pink sibling carries a white segment in position 1 from Dad and gold segments in positions 2 and 3 from Dad. From Mom, they inherited a green segment in position 1, magenta in position 2 and green in position 3.

IBC Match 1 – Looking at the blue siblings, we see that based on the DNA inherited from Pink Child 5’s parents, Pink Child 5 matches Blue Child 4 with white, gold and gold in positions 1-3, even though they weren’t inherited from the same parent in Blue Child 4. I circled this match in blue.

IBC Match 2 – Pink Child 5 also matches Blue Children 1 and 2 (red circles) because Pink Child 5 has green, magenta, and green in positions 1-3 and so do Blue Children 1 and 2. However, Blue Children 1 and 2 inherited the green and magenta segments from Mom and Dad respectively, not just from one parent.

Pink Child 5 matches Blue Children 1, 2 and 4, but not because they match by descent, but because their DNA zigzags back and forth between the blue children’s DNA contributed by both parents.

Therefore, while Pink Child 5 matches three of the Blue Children, they do not match either parent of the Blue Children.

IBC Match 3 – Pink Child 6 matches Blue Child 3 with white, magenta and gold in positions 1-3 based on the same colors of dots in those same positions found in Blue Child 3 – but inherited both paternally and maternally.

You can see that if we had the four parents available to test, that none of the Pink Children would match either the Blue Children’s mother or father and none of the Blue Children would match either of the Pink Children’s mother or father.

This is why we can’t use either siblings or close family relatives for triangulation.

Distant Cousins Are Best for Triangulation & Here’s Why

When triangulating with 3 people, the most recent common ancestor (MRCA) intersection of the closest two people is the place at which triangulation turns into only two lines being compared and ceases being triangulation. Triangle means 3.

If siblings are 2 of the 3 matching people, then their parents are essentially being compared to the third person.

If you, your aunt/uncle, and a third person match, your grandparents are the place in your tree where three lines converge into two.

The same holds true if you’re matching against a sibling pair on your match’s side, or a match and their aunt/uncle, etc.

The further back in your tree you can push that MRCA intersection, the more your triangulated match provides confirming evidence of a common ancestor and that the match is valid and not caused by random recombination.

That’s exactly what the descendants of Charles Dodson have been able to do through triangulation with multiple descendants from several of his children.

It’s also worth mentioning at this point that the reason autosomal DNA testing uses hundreds/thousands of base pairs in a comparison window and not 3 or 6 dots like in my example is that the probability of longer segments of DNA simply randomly matching by chance is reduced with length and SNP density which is the number of SNP locations tested within that cM range.

Hence a 7 cM/500 SNP minimum is the combined rule of thumb. At that level, roughly half of your matches will be valid and half will be identical by chance unless you’re dealing with endogamy. Then, raise your threshold accordingly.

Ok, So Where are We? A Triangulation Checklist for You!

I know this has been a relatively long educational article, but it’s important to really understand that testing close relatives is VERY important, but also why we can’t effectively use them for triangulation.

Here’s a handy-dandy summary matching/triangulation checklist for you to use as you work through your matches.

  • You inherit half of each of your parents’ DNA. There is no other place for you to obtain or inherit your DNA. There is no DNA fairy sprinkling you with DNA from another source:)
  • DNA does NOT skip generations, although in occasional rare circumstances, it may appear that this happened. In this situation, it’s incumbent upon you, the genealogist, to PROVE that an exception has occurred if you really believe it has. Those circumstances might be pedigree collapse or perhaps imputation. You’ll need to compare matches at vendors who provide a chromosome browser, triangulation, and full shared match list information. Never assume that you are the exception without hard and fast proof. We all know about assume, right?
  • Your siblings inherit half of your parents’ DNA too, but not the same exact half of your parent’s DNA that you other siblings did (unless they are identical twins.) You may inherit the exact same DNA from either or both of your parents on certain segments.
  • Your matches may match your parents on different or an additional segment that you did not inherit.
  • Every segment has an individual history. Evaluate every matching segment separately. One matching segment with someone could be maternal, one paternal, and one identical by chance.
  • You can confirm matches as valid if your match matches one of your parents, and you match one of your match’s parents. Parental Phasing is when your match matches your parent. Parental Cross-Matching is when you both match one of each other’s parents. To be complete, both people who match each other need to match one of the parents of the other person. This rule still holds even if you have a known common ancestor. I can’t even begin to tell you how many times I’ve been fooled.
  • 15-20% (or more with endogamy) of your matches will be identical by chance because either your DNA or your match’s DNA aligns in such a way that while they match you, they don’t match either of your parents.
  • Your siblings, aunts, and uncles will often inherit the same DNA as you – which means that identical by chance matches will also match them. That’s why we don’t use close family members for triangulation. We do utilize close family members to generate common match hints. (Remember the 20 cM shared match caveat at Ancestry)
  • While your siblings, aunts, and uncles are too close to use for triangulation, they are wonderful to identify ancestral matches. Some of their matches will match you as well, and some will not because your close family members inherited segments of your ancestor’s DNA that you did not. Everyone should test their oldest family members.
  • Triangulate your close family member’s matches separately from your own to shed more light on your ancestors.
  • Endogamy may interfere with parental phasing, meaning you may match because you and/or your match may have inherited some of the same DNA segment(s) from both sides of your tree and/or more DNA than might otherwise be expected.
  • Pedigree collapse needs to be considered when using parental phasing, especially when the same ancestor appears on both sides of your family tree. You may share more DNA with a match than expected.
  • Conversely, with pedigree collapse, your match may not match your parents, or vice versa, if a segment happens to have recombined in you in a way that drops the matching segments of your parents beneath the vendor’s match threshold.
  • While you will match all of your second cousins, you will only match approximately 90% of your third cousins and proportionally fewer as your relationship reaches further back in time.
  • Not being a DNA match with someone does NOT mean you’re NOT related to them, unless of course, you’re a second cousin (2C) or closer. It simply means you don’t carry any common ancestral segments above vendor thresholds.
  • At 2C or closer, if you’re not a DNA match, other alternative situations need to be considered – including the transfer/upload of the wrong person’s DNA file.
  • Imputation, a scientific process required of vendors may interfere with matching, especially in more distant relatives who have tested on different platforms.
  • Imputation artifacts will be less obvious when people are more closely related, meaning closer relatives can be expected to match on more and larger segments and imputation errors make less difference.
  • Imputation will not cause close relatives, meaning 2C or closer, to not match each other.
  • In addition to not supporting segment matching information, Ancestry down-weights some segments, removes some matching DNA, and does not show shared matches below 20cM, causing some people to misinterpret their lack of common matches in various ways.
  • To resolve questions about matching issues at Ancestry, testers can transfer/upload their DNA files to MyHeritage, FamilyTreeDNA, and GEDmatch and look for consistent matches on the same segment. Start and end locations may vary to some extent between vendors, but the segment size should be basically in the same location and roughly the same size.
  • GEDmatch does not use imputation but allows larger non-matching segments to combine as a single segment which sometimes causes extremely “generous” matches. GEDmatch matching is less reliable than FamilyTreeDNA or MyHeritage, but you can adjust the matching thresholds.
  • The best situation for matching is for both people to test at the same vendor who supports and provides segment data and a chromosome browser such as 23andMe, FamilyTreeDNA, or MyHeritage.
  • Siblings cannot be used for triangulation because the most recent common ancestor (MRCA) between you and your siblings is your parents. Therefore, the “three” people in the triangulation group is reduced to two lines immediately.
  • Uncles and aunts should not be used for triangulation because the most recent common ancestors between you and your aunts and uncles are your grandparents.
  • Conversely, you should not consider triangulating with siblings and close family members of your matches as proof of an ancestral relationship.
  • A triangulation group of 3 people is only confirmation as far back as when two of those people’s lines converge and reach a common ancestor.
  • Identical by chance (IBC) matching occurs when DNA from the maternal and paternal sides are mixed positionally in the child to resemble a maternal/paternal side match with someone else.
  • Identical by chance DNA admixture (when compared to a match) could have occurred in your parents or grandparent’s generation, or earlier, so the further back in time that people in a triangulation group reach, the more reliable the triangulation group is likely to be.
  • The larger the segments and/or the triangulation group, the stronger the evidence for a specific confirmed common ancestor.
  • Early families with a very large number of descendants may have many matching and triangulated members, even 9 or 10 generations later.
  • While exactly 50% of each ancestor’s DNA is not passed in each generation, on average, you will carry 7 cM of your ancestors 10 generations back in your tree. However, you may carry more, or none.
  • The percentage of matching descendants decreases with each generation beyond great-grandparents.
  • The ideal situation for triangulation is a significant number of people, greater than three, who match on the same reasonably sized segment (7 cM/500 SNP or larger) and descend from the same ancestor (or ancestral couple) through different children whose spouses in descendant generations are not also related.
  • This means that tree completion is an important factor in match/triangulation reliability.
  • Triangulating through different children of the ancestral couple makes it significantly less likely that a different unknown common ancestor is contributing that segment of DNA – like an unknown wife in a descendant generation.

Whew!!!

The Bottom Line

Here’s the bottom line.

  1. Don’t use close relatives to triangulate.
  2. Use parents for Parental Phasing.
  3. Use Parental Cross-Matching when possible.
  4. Use close relatives to look for shared common matches that may lead to triangulation possibilities.
  5. Triangulate your close relatives’ DNA in addition to your own for bonus genealogical information. They will match people that you don’t.
  6. For the most reliable triangulation results, use the most distant relatives possible, descended through different children of the common ancestral couple.
  7. Keep this checklist of best practices, cautions, and caveats handy and check the list as necessary when evaluating the strength of any match or triangulation group. It serves as a good reminder for what to check if something seems “off” or unusual.

Feel free to share and pass this article (and checklist) on to your genealogy buddies and matches as you explain triangulation and collaborate on your genealogy.

Have fun!!!

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Disclosure

I receive a small contribution when you click on some of the links to vendors in my articles. This does NOT increase the price you pay but helps me to keep the lights on and this informational blog free for everyone. Please click on the links in the articles or to the vendors below if you are purchasing products or DNA testing.

Thank you so much.

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How to Download Your DNA Matching Segment Data and Why You Should

There are two or three types of data that testers may be able to download from DNA testing sites. Genealogy customers need to periodically download as much as possible.

  1. Raw data files needed for transferring DNA files from the company where you tested to other testing or analysis/comparison sites such as FamilyTreeDNA, MyHeritage, and GEDmatch for matching and other tools.
  2. Matching segment files which detail your matches, segment by segment with people whom you match.
  3. Match information files that provide you with additional information about your matches. What’s included varies by vendor.

This type of information is not uniformly available from all vendors, but is available as follows:

Vendor Raw Data File Matching Segment File Match Information File
FamilyTreeDNA Yes Yes Yes
MyHeritage Yes Yes Yes
23andMe Yes Yes Yes
Ancestry Yes No No
GedMatch Not a testing company, so no Yes Yes

I have provided step-by-step information about how to download your raw DNA data files and upload them to other vendors in a series of articles that you can find here.

Some of the answers in the table above need caveats because each vendor is different. Let’s take a look.

Matching Segment Files

In this article, I’ll provide information about how to download your matching segment and match information file(s).

Unfortunately, Ancestry does not provide any segment data at all, nor do they provide a way to download your match information. Third-party tools that did this for you have been banned by Ancestry, under threat of legal action, so this information is no longer available to Ancestry customers.

You can’t obtain this information from Ancestry, but you can transfer your DNA file to other vendors such as FamilyTreeDNA, MyHeritage and the third-party site, GEDmatch where you’ll receive additional matches. Some Ancestry matches will have transferred elsewhere as well, and you can take advantage of your matching segment information.

Why Do I Want a Matching Segment File?

The matching segment file provides you with information about exactly how and where you match each person.

Here’s an example that includes the match name, chromosome, start and end location of the match along with the total number of CentiMorgans (cM) and total SNPs in the matching segment. Your matching segment file consists of hundreds/thousands of rows of this information.

Determining who matches you on the same segment is important because it facilitates the identification of common ancestors. Segment matching is also the first step in triangulation which allows you to confirm descent from common ancestors with your matches.

I wrote about triangulation at each vendor in the following articles:

Matching and Triangulation help you sort out legitimate matches, and which ancestors that DNA segment comes from.

Sorting For Legitimate Matches

On each segment location of your DNA, you will match:

  • People from your Mom’s side
  • People from your Dad’s side
  • People that are identical by chance (IBC) where they match you because part of the DNA from your Mom’s side and part from your Dad’s side just happens to look like their DNA (or vice versa.)

You can see how matching works in this example of 10 DNA locations. You inherited half of your Mom’s DNA and half of your Dad’s.

  • Legitimate maternal matches to you on this segment will have all As in this location.
  • Legitimate paternal matches to you will have all Cs in this location.
  • Identical by chance matches will match you, because they have the same DNA as both of your parents that you carry – interspersed. They will not match either of your parents individually.

IBC matches DO technically match you, but accidentally. In other words, they are identical by chance (IBC) because they just happen to match the DNA of both of your parents intermixed. Conversely, you can match the DNA of their parents intermixed as well. Regardless of why, they are not a legitimate maternal or paternal match to you.

For example, you can see that the identical by chance (IBC) match to you, above, won’t match the legitimate maternal or legitimate paternal matches.

When comparing your matches on any segment, you’ll wind up with a group of people who match you and each other on your maternal side, a group on your paternal side, and “everyone else” who is IBC.

I wrote about IBD, identical by descent DNA and IBC, identical by chance DNA and how that works, here.

A downloadable segment match file allows you to sort all of your matches by chromosome and segment. That’s the first step in determining if your matches match each other – which is how to determine if people are legitimate matches or IBC.

Additionally, these files allow you to utilize features at DNAPainter along with the tools at DNAGedcom and Genetic Affairs.

Match Information File

There’s a second file you’ll want to download as well except at 23andMe who includes all of the information in one file. You’ll want to download these files from each vendor at the same time so they are coordinated and include the same matches from the same time.

Downloading the second file, your match information, provides additional information which will be helpful for your genealogy. The information in this file varies by vendor, but includes items such as, but not limited to:

  • Tree link
  • Haplogroup
  • Match date
  • Predicted Relationship Range
  • Actual Relationship
  • Total shared cM
  • Longest segment cM
  • Maternal or paternal bucket (FamilyTreeDNA)
  • Notes
  • Email
  • Family Surnames
  • Location
  • Percent of shared DNA

You never know when vendors are going to change something that will affect your matches, like 23andMe did last fall, so it’s a good idea to download periodically.

Downloading your segment match and match information files are free, so let’s do this.

Downloading Your Segment Match & Information Files

FamilyTreeDNA

Sign on to your account.

click images to enlarge

Under your Family Finder Autosomal DNA test results, click on Chromosome Browser.

On the chromosome browser page, at the top right, click on Download All Segments.

Caveat – if you access the chromosome browser through the Family Finder match page, shown below, you will receive the segment matches ONLY for the people you have selected.

After selecting specific matches, as shown above, the option on the chromosome browser page will only say “Download Segments.” It does NOT say “Download All Segments.”

Clicking on this link only downloads the segments that you match with those people, so always be sure to access “Download ALL Segments” directly through the chromosome browser selection on your Autosomal DNA Family Finder menu without going to your match page and selecting specific matches.

The segment download file includes only the segments, but not additional information, such as which side, maternal or paternal, those matches are bucketed to, surnames and so forth. You need to download a second file.

To download additional information about your matches, scroll to the very bottom of your Family Finder match page and click on either Download Matches or Download Filtered matches. If you’ve used a filter such as maternal or paternal, you’ll receive only those matches, so be sure no filters are in use to download all of your matches’ information.

Your reports will be downloaded to your computer, so save them someplace where you can find them.

MyHeritage