Pedigree Collapse and DNA – Plus an Easy-Peasy Shortcut

Pedigree collapse can be responsible for you sharing more DNA than expected with another person.

What is pedigree collapse?

Pedigree collapse occurs when you descend from the same ancestor(s) through more than one path. In other words, you descend from those ancestors through two different children. Therefore, when matching with someone else who descends through those ancestors, you may share more DNA than would be expected from that level of relationship on the surface, meaning without pedigree collapse.

Endogamy is different and means that you descend from a community of ancestors who descend from the same group of ancestors. Often out-marriage is discouraged or otherwise impossible, so all of the group of people share common ancestors, which means they often match on segments without sharing close ancestors. Examples of descent from endogamous populations are Jewish, Amish, Brethren, Acadian, Native Hawaiian, Māori, and Native American people, among others.

I wrote about the difference between pedigree collapse and endogamy in the article, What’s the Difference Between Pedigree Collapse and Endogamy?

I’ve also written about endogamy in the following articles:

Degrees of Consanguinity

If you’re a genealogist, and especially if you’ve worked with Catholic church records, you’ve probably heard of “degrees of sanguinity,” which are prohibited blood relationships in marriage. For example, siblings are prohibited from marrying because they are too closely related, according to church doctrine.

By SVG remake by WClarke based on original by User:Sg647112c – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=54804980

Today, we think of the genetic results of inbreeding, but originally, relationships (and consanguinity) also had to do with inheritance.

Essentially, marriages are prohibited by degree of sanguinity, and that degree is calculated based on this relationship chart. Prohibited degrees of consanguinity changed over time. Sometimes, a priest granted dispensation for a couple to wed who was of a prohibited degree of sanguinity. That’s a genealogy goldmine because it tells you where to look for common ancestors. It also tells you something else – that you may share more DNA with other descendants of that couple than one would otherwise expect.

More Than You Ever Expected

Recently, I’ve been working with an academic research team on a very interesting ancient DNA case that involves pedigree collapse. Doing the genealogy and genetic work on how much DNA was expected in a match without pedigree collapse, and how much was expected with pedigree collapse, was very interesting.

The team was working to confirm relationships between people in a cemetery. The burials shared more DNA than anticipated for who the people were believed to be. Enter pedigree collapse.

I can’t disclose the circumstances just yet – but I will as soon as possible. It’s an extremely interesting story.

We needed to ensure that readers, both academic and more generally understood pedigree collapse and our calculations. Why did burials share higher than expected DNA than indicated by the expected relationships? This puzzle becomes much more interesting when you add in pedigree collapse.

Academic researchers and scientists have access to models and mathematical algorithms that normal air-breathing humans don’t have easy access to.
So, what do you do if you and a match have a known pedigree collapse in your tree? How much DNA can you expect to share, and how do you calculate that?

These are all great questions, so let’s take a look.

I’m sharing the PowerPoint slides I prepared for our team on this topic. I’ve removed anything that would identify or even hint at the project and modified the slides slightly for easier consumption.

This presentation has never been given publicly, so you’re first! It seemed a waste to do this work and not share it!

Pedigree Collapse and DNA

Pedigree collapse occurs when you share an ancestor or ancestors through different pathways. In this case, the person at the bottom is the child of parents who were third cousins, but the father’s grandparents were also first cousins.

First cousin marriages were common in the not-too-distant past. Today, you could easily marry your third or fourth cousin and not even realize it unless someone in your family just happened to be a genealogist.

Genealogists use various tools to calculate the expected amount of shared DNA in relationships – first cousins, siblings, or half-siblings, for example. Both the Shared cM Project at DNAPainter and SegcM at DNA-Sci Tools provide tools.

Take a look at the article, DNA: In Search of…Full and Half-Siblings, for some great examples.

First cousins share common grandparents. Their child inherits DNA from two paths that lead back to the same ancestors. Some of that DNA will be the same, meaning the child will or can inherit the same ancestral segment from both parents, and some will be different segments from those ancestors that the parents do not share with each other.

Inheritance – How It Works

Let’s look at inheritance to see how this happens.

Let’s start with full and half-siblings.

Each child inherits half of their DNA from each parent, but not entirely the same half (unless they are identical twins.)

Therefore, full siblings will match on about 50% of their DNA, which is illustrated by the segments on the chromosome browser. However, and this will be important in a minute, about 25% of their DNA is exactly the same, when compared to each other, on the chromosome inherited from their father and mother at the same location.

On the chromosome browser, you can see that three siblings do match. One sibling (the grey background chromosomes) is the person both other full siblings are being compared to, in the example above.

What you can’t determine is whether they share the exact same DNA on both their mother and father’s Chromosome 1, where the matches overlap, for example. We know they both match their sibling, but the top person could match the sibling due to a match from their paternal chromosome in that location, and the bottom person could match due to their maternal chromosome. There’s no way to know, at least not from that view.

The areas where the siblings share exactly the same DNA on both their maternal and paternal chromosome, both, with each other are called Fully Identical REgions (FIR), as compared to Half Identical Regions (HIR) where the siblings match on either their maternal or paternal copy of the chromosome, but not both.

23andMe used to provide a tool that displayed both types of matches.

Since the data exposure incident at 23andMe, they no longer provide this lovely tool, and since that help page is now gone as well, I doubt this view will ever be returned. Fortunately, I grabbed a screenshot previously.

The dark purple segments are fully identical, meaning that these two full siblings match on both their maternal and paternal chromosomes in that location. The magenta are half identical, which means they match on EITHER the maternal or paternal chromosome in that location but not on both chromosomes. Of course, no color (light grey) means there is no match at that location.

Please note that because 23andMe counts fully identical regions (FIR) twice, their total matching cMs are elevated. The other companies do NOT count those regions twice.
GEDmatch also shows both full and half-identical regions as described more fully, here.

In this full-sibling example from GEDmatch, the green segments are fully identical regions across both the maternal and paternal chromosomes.

The definition of FIR is that two people match on both their mother’s and father’s DNA on the same chromosome. Therefore, in following generations, there technically should not be FIR matches, but in some instances we do find FIR matches outside of full siblings.

Moving down another generation, first cousins may share SOME fully identical DNA, especially if they are from an endogamous population or their mothers are related, but less, and it’s generally scattered.

Here’s my Mom’s GEDmatch comparison to her first cousin. The purple-legend segment shows a match, and the green within that match shows fully identical locations.

You can easily see that these are very scattered, probably representing “chance” or population-based fully identical matching locations within a segment. Comparatively, the green FIR segments for full siblings are dense and compact, indicating a segment that is fully identical.

Evaluating matches for dense FIR segments (known as runs of homozygosity – ROH) is a good indicator of parental relatedness.

Double Cousins

Of course, if these people were double first cousins, where the wives of the siblings were sisters to each other – the first cousins would have large patches of dense green FIR segments.

First cousins share grandparents.

Double first cousins occur when two people share both sets of grandparents, meaning that brothers marry sisters. Normal first cousins share about 12.5% of their DNA, but double first cousins share about 25% of their DNA.

In this case, Sharon and Donna descend from two brothers, James and Henry, who were sons of Joseph and Jane. In this scenario, James and Henry married unrelated women, so Sharon and Donna are first cousins to each other.

Double first cousins share both sets of grandparents so they would inherit FIR from both sets of siblings.

You need to be aware of this, but for now, let’s stick with non-double relationships. You’re welcome!

DNA Inheritance

Here’s a different example of DNA inheritance between two siblings.

  1. You can see that in the first 50 cM segment, both siblings inherited the same DNA from both parents, so they match on both their mother’s and father’s chromosomes. They match on both the 50 cM green and 50 cM pink segments. 23andMe would count that as 100 cMs, but other vendors only count a segment IF it matches, NOT if it matches twice. So, other vendors count this as a 50 cM match.
  2. In column two, these two people don’t match at all because they inherited different DNA from each parent. In this example, Person 1 inherited their maternal grandmother’s segment, and Person 2 inherited their maternal grandfather’s segment.
  3. In column three, our siblings match on their paternal grandmother’s segment.
  4. In column four, no match again.

How much can we expect to inherit at different levels – on average?

Different tools differ slightly, and all tools provide ranges. In our example, I’ve labeled the generations and how much shared DNA we would expect – WITHOUT pedigree collapse.

Ancestral couple Inherited cM Inherited %
Gen 1 – Their children 3500 cM 50
Gen 2 – Grandchildren 1750 cM 25
Gen 3 – Great-Grandchildren 875 cM 12.5
Gen 4 – GG-Grandchildren 437.5 6.25
Gen 5 – GGG-Grandchildren 218.75 3.125
Gen 6 – GGGG-Grandchildren 109.375 1.5625
Gen 7 – GGGG-Grandchildren 54.6875 .078125

Please note that this is inherited DNA, not shared (matching) DNA with another person.

Adding in pedigree collapse, you can see that we have three Gen 1 people involved, three Gen 2 descendants, and two Gen 3 and Gen 4 people.

Each of those people inherit and pass on segments from our original couple at the top.
We have three distinct inheritance paths leading from our original couple to Gen 5.
We have a first cousin marriage at Gen 2, at left, which means that their child, Gen 3, will have an elevated amount of the DNA of their common ancestors.

In Gen 4, two people marry who both descend from a common couple, meaning their child, Gen 5, descends from that couple in three different ways.

Did your eyes just glaze over? Well, mine did, too, which is why I had to draw all of this out on paper before putting it into PowerPoint.

The Gen 5 child inherits DNA from the ancestral couple via three pathways.
The next thing to keep in mind is that just because you inherit the DNA from an ancestor does not mean you match another descendant. Inheritance is not matching.

You must inherit before you can match, but just because you and someone else have inherited a DNA segment from a common ancestor does not guarantee a match. Those segments could be in different locations.

Categories of DNA

When dealing with inheritance and descent, we discuss four categories of DNA.

  • In the first generation, full siblings will, in about 25% of their locations, share the same DNA that has been inherited from both parents on the same chromosome. In other words, they match each other both maternally and paternally at that location. Those are FIR.
  • The DNA you inherit from an ancestor.
  • The DNA that both you and your cousin(s) inherit from a common ancestor and match on the same location. This is shared DNA.
  • The DNA that both you and your cousin(s) inherit from a common ancestor, but it’s not in the same location, so you do not match each other on that segment. Just because you inherit DNA from that ancestor does not necessarily mean that your cousin has the same DNA from that ancestor. This is inherited but not shared.

Inheritance is Not The Same as Matching

Inheritance is not the same thing as matching.

Inheriting our ancestor’s DNA isn’t enough. We need to match someone else who inherited that same segment in order to attribute the segment to that specific ancestor.

Depending on how close or distant the relationship, two people may share a lot of DNA (like full siblings), or one segment in more distant matches, or sometimes none at all. As we reach further back in time, we inherit less and less of our increasingly distant ancestors’ DNA, which means we match increasingly fewer of their descendants. I wrote about determining ancestral percentages in the article,  Ancestral Percentages – How Much of Them is in You?

Based on how much DNA we share with other known relatives, we can estimate relationships.

Pedigree collapse, where one descends from common ancestors more than once, increases the expected amount of inherited DNA, which in turn increases the probability of a shared match with other descendants.

Ancestral Couple Matching Between Shared DNA ~cM Shared DNA ~% Range (Shared cM Project) FIR – Identical DNA
Generation 1 Full Siblings 2600 50 1613-3488 25%
Generation 2 First Cousins 866 12.5 396-1397 0
Generation 3 Second Cousins 229 3.125 41-592 0
Generation 4 Third Cousins 73 0.78125 0-234 0

Here’s an example through third cousins, including expected FIR, fully identical regions where full siblings match each other on both their maternal and paternal chromosomes in the same location.

I provided a larger summary chart incorporating the information from public sources, here, minus FIR.

Of course, double cousins, where two pairs of siblings marry each other, represent another separate level of complexity. DNA-Sci’s Double Cousin Orogen explains this here and also provides a tool.

Double cousins, meaning when two pairs of siblings marry each other, are different from doubly related.

Doubly related means that two people descend from common ancestors through multiple paths, meaning multiple lines of descent. Doubly related is pedigree collapse. Double cousins is pedigree collapse on steroids.

Pedigree Collapse, aka Doubly Related

Calculating expected inherited DNA from multiple lines of descent is a bit more challenging.

A handy-dandy chart isn’t going to help with multiple relationships because the amount of expected shared DNA is based on the number of and distance of relationships.

Please note that this discussion excludes X-DNA matching which has its own inheritance path.

It’s time for math – but I promise I’ll make this relatively easy – pardon the pun.

What’s Behind the Math?

So, here’s the deal. I want you to understand why and how this works. You may not need this information today, but eventually, you probably will. This is one of those “refer back to it” articles for your personal library. Read this once as a conceptual overview, then read it again if you need to work through the relationships.

This is easy if you take it one step at a time.

First, we calculate each path separately.

In the first generation, full siblings inherit identical (FIR) DNA on both their mother’s and father’s chromosomes.

In the second generation, the male inherits the maternal segment, and the female inherits the paternal segment.

In the third generation, their child inherits those segments intact from both of their parents. The child inherits from the ancestral couple twice – once through each parent.

In generation 1, those two segments were FIR, fully identical regions. Both of those men married unrelated wives. When their children, Gen 2, were born, they had either the maternal or paternal segment from their father because they had an entirely different segment in that location from their mother.

However, the child in Gen 3 inherited the original green segment from their father and the original pink segment from their mother – reuniting those FIR segments in later generations.

First Cousin’s Child

Let’s calculate the inheritance for the child of those two first cousins who married.

Ancestral couple Inherited cM Inherited %
Gen 3 – Great-Grandchildren 875 cM 12.5
Gen 3 – Great-Grandchildren 875 cM 12.5
Total 1750 cM 25

Normally, a Gen 3 person inherits roughly 875 cM, or 12.5% of their great-grandparent’s DNA. However, since their grandparents were first cousins, they inherit about twice that amount, or 1750 cM.

While a Gen 3 person inherits as much as a grandchild (25%) normally would from the original couple, they won’t match on all of that DNA. When matching, we need to subtract some of that DNA out of the equation for two reasons:

  • In the first generation, between siblings, some of their DNA was fully identical and cannot be identified as such.
  • In the second generation, they will each have some parts of the ancestral couple’s DNA that will not match the other person. So, they inherit the same amounts from their common ancestors, but they can only be expected to match on about 25% of that amount two generations later.

However, the child of first cousins who marry inherits more DNA of the common ancestors than they would if their parents weren’t related. It’s just that some of that DNA is the same, potentially on the maternal and paternal chromosomes again, and some won’t match at all.

While matching DNA is the whole point of autosomal DNA testing, fully identical DNA matching regions (FIR) cannot be identified that way. For the most part, other than identifying full and half-siblings, sometimes pedigree collapse, and parent-relatedness, fully identical DNA isn’t terribly useful for genealogy. However, we still need to understand how this works.

It’s OK if you just want to say, “I know we’ll share more DNA due to pedigree collapse,” but if you want to know how much more to expect, keep reading. I’d really like for you to understand use cases and be able to track those segments.

Remember, we will learn a super-easy shortcut at the end, so for now, just read. It’s important to understand why the shortcut works.

Sibling Inheritance Versus Matching

In order to compare apples to apples, sometimes we need to remove some portion of DNA in our calculations.

Remember story problems where you had to “show your work”?

Calculating Expected DNA

Here’s the step-by-step logic.

Ancestral couple Inherited Non-Identical cM Inherited %
Gen 1 first son 3500 50
Gen 1 second son 3500 50
Less identical segments (FIR) -1750 (subtracted from one child for illustration) 25
Gen 2 son 1750 25
Gen 2 daughter married Gen 2 son 875 12.5
Gen 3 – Their child path through Gen 2 son 875 cM 12.5
Gen 3 – Their child path through Gen 2 mother 437.5 cM 6.25
Their child total without removing identical segments 1750 cM 25
Their child total after removing identical segments 1312.5 18.75

Category cMs Most Probable Degree Relationship
No Pedigree Collapse 875 98% Great grandparent or great-grandchild, great or half aunt/uncle, great or half niece/nephew, 1C 3
Pedigree Collapse without identical segment removal 1750 100% Grandparent, grandchild, aunt/uncle, half-sibling, niece/nephew 2
Pedigree Collapse after identical segment removal 1312.5 56% grandparent, grandchild, aunt/uncle, niece/nephew, half-sibling 2

Just because you HAVE this much shared (and/or identical) DNA doesn’t mean you’ll match on that DNA.

Next, let’s look at Gen 5 child who inherited three ways from the ancestors.

If you think, “This will never happen,” remember that it did, which is why I was working through this story problem. It’s not uncommon for families to live in the same area for generations. You married who you saw – generally, your family and neighbors, who were likely also family.

Let’s take a look at that 5th generation child.

The more distantly related, the less pedigree collapse affects matching DNA. That’s not to say we can ignore it.

Here’s our work product. See, this isn’t difficult when you take it step by step, one at a time.

Ancestral couple Inherited Non-Identical cM Inherited %
Gen 3 Child total after removing identical segments 1312.5 18.75
Gen 4 father – half of Gen 3 father 656.25 9.375
Gen 5 child – half of Gen 4 father 328.125 4.6875
Gen 5 child – mother’s side calculated from ancestral couple normally 218.75 3.125
Total for Gen 5 Child 546.875 7.8125

Inheritance Ranges

Lots of factors can affect how much DNA a person in any given generation inherits from an ancestor. The same is true with multiple paths from that same ancestor. How do we calculate multiple path inheritance ranges?

As with any relationship, we find a range, or combined set of ranges for Gen 5 Child based on the multiple pathways back to the common ancestors.

Gen 5 Child Inherited Non-Identical cM Inherited %
Without removing either paternal or maternal identical cMs 656.25 9.375
After removing paternal identical cMs only 546.875 7.8125

 

After removing maternal cMs only 546.875 7.8125

 

After removing both paternal and maternal identical cMs 362.50 6.25
Normal Gen 5 no pedigree collapse 218 3.125

What About Matching?

Inheritance and matching are different. Most of the time, two people are unlikely to share all of the DNA they inherited from a particular ancestor. Of course, inheriting through multiple paths increases the likelihood that at least some DNA from that ancestor is preserved and that it’s shared with other descendants.

Two people aren’t expected to match on all of the segments of DNA that they inherit from a particular ancestor. The closer in time the relationship, the more segments they will inherit from that ancestor, which increases the chances of matching on at least one or some segments.

Clearly, pedigree collapse affects matching. It’s most pronounced in closer relationships, but it may also be the only thing that has preserved that ONE matching segment in a more distant relationship.

So, how does pedigree collapse actually affect the likelihood of matching? What can we actually expect to see? Is there a name for this and a mathematical model to assist with calculations?

I’m so glad you asked! It’s called Coefficient of Relationship.

Coefficent of Relationship

My colleague, Diahan Southard, a scientist who writes at YourDNAGuide has authored two wonderful articles about calculating the statistical effects of pedigree collapse.

You can also read another article about the methodology of calculating coefficient of relationship, here, on WaybackMachine.

Diahan is a math whiz. I’m not, so I needed to devise something “quick and dirty” for my own personal use. I promised you a “cheat sheet,” so here’s the methodology.

Two Inheritance Paths – First and Third Cousins

Let’s look at an example where two people are both first cousins and third cousins because their grandparents were also first cousins.

Let’s calculate how these two people are related. They are first cousins and also third cousins.

When calculating the effects of pedigree collapse, we calculate the first relationship normally, then calculate the second relationship and add a portion of the result.

Here’s the math.

Using the Shared cM Project for the expected amount of shared DNA for both relationships, we’ve calculated the expected range for this pedigree collapse relationship.

Tying this back to degrees of relatedness.

Let’s look at ways to do Quick Calculations using the publicly available Shared cM charts and my composite tables, here.

Using Average Shared DNA

This first methodology uses average expected amount of shared, meaning matching, DNA. Please note, I’m not necessarily expecting you to DO this now, just read to follow.

Using Average Inherited DNA

Here’s a second method using average inherited DNA, meaning people wouldn’t be expected to match on all of the inherited DNA – just a portion.

You can’t always use the shared cM charts because all relationships aren’t represented, so you may need to use the amount of expected inherited DNA instead of shared DNA amounts.

Methodology Differences

Remember, none of these methodologies are foolproof because DNA inheritance is random. You may also have additional relationships that you’re aware of.

So, what’s the easiest method? Neither, actually. I’ve found an even easier method based on these proven methodologies.

Easy-Peasy Pedigree Collapse Shortcut Range Calculation in 4 Steps

Now that you understand the science and reasoning behind all of this, you can choose from multiple calculation methodologies after drawing a picture of the relevant tree.

You’re probably wondering, “What’s the easiest way to do this?”

  • These quick calculation methods are the easiest to work with for non-scientists and non-math whizzes. These are the calculations I use because, taking into account random recombination, you can’t do any better than get close.
  • Also, remember, if you’re dealing with double relationships, meaning double first cousins, you’ll need to take that into consideration, too.
  • If endogamy is involved, your matches will be higher yet, and you should use the highest calculations below because you need to be on the highest end of the range – and that may still not be high enough.

In these Easy-Peasy calculations, you calculate for the lowest, then the highest, and that’s your range. Please note that these are options, and truly, one size does not fit all.

  1. For the lowest end of the range, simply use the average of the highest relationship. In this case, that would be 1C, which is 866 cM. Remember that you may not share DNA with third cousins. 10% of third cousins don’t share any DNA, and 50% of fourth cousins don’t.
  2. For the highest end of the range, find the second relationship in the Shared cM chart, divide the average by half, and add to the value from the closest relationship. In this case, half of the 3C value of 76 is 38.
  3. Add 38 to 866 for the highest end of the range of 904.
  4. If there’s yet another path to ANY shared ancestor, add half that amount too to calculate the high end of the range – unless it’s 4C or more distant, then don’t add anything.

You can see that this easy-peasy range calculation for pedigree collapse compares very well to the more complex but still easy calculations.

  • Easy-peasy calculation: 866-904
  • Other calculation methods: 850-903
  • For this same relationship combination, Diahan’s statistical calculation was 850 cM.

Back to Genealogy

What’s the short story about how pedigree collapse affects genealogy?

Essentially, in close generations, meaning within a few generations of two first cousins marrying, descendants can expect to inherit and share significantly more DNA of the common ancestors, but not double the amount. As we move further away from those marriages in time, the effect becomes less pronounced and more difficult to detect. You can see that effect when calculating multiple paths where at the fourth cousin level, or more distant, those cousins have a 50% or greater possibility of not sharing DNA segments.

Of course, with multiple paths to the same ancestor, your chances of inheriting at least some segments from the common ancestor are increased because their DNA descends through multiple paths.

Today, close marriages are much less common and have been for several generations in many cultures, so we see fewer instances where pedigree collapse makes a significant difference.

Within a population or group of people, if pedigree collapse becomes common, meaning that there are multiple paths leading back to common ancestors, like our three-path example, DNA segments from the common ancestors are found among many people. Significant pedigree collapse becomes endogamy, especially if marriage outside of the group is difficult, impossible, or discouraged.

Normally, pedigree collapse is not recorded in actual records. It’s left to genealogists to discover those connections.

The exception, of course, is those wonderful Catholic parish records where the priest granted dispensations. Sometimes, that’s our only hint to earlier genealogy. In the case of the marriage of Marie-Josesphe LePrince to Jacques Forest, the priest wrote “dispense 3-3 consanguinity,” which tells us that they shared great-grandparents. It also tells us that their grandparents were siblings, that the bride and groom were second cousins, and that their children and descendants inherited an extra dose of DNA from their common great-grandparents.

How does that affect me today? Given that I’m their seventh-generation descendant – probably not at all. Of course, they are Acadian, and the Acadians are highly endogamous, which means I match many Acadians because all Acadians share the DNA of just a few founders, making it almost impossible to track segments to any particular ancestor. If it weren’t for endogamy, I would probably match few, if any, of their descendants.

Now, when you see those Catholic church dispensations or otherwise discover pedigree collapse, you can be really excited, because you understand the effects of pedigree collapse and how to calculate resulting matches! You might, just might, have retained a DNA segment from those ancestors because you inherited segments through multiple paths – increasing the probability that one survived.

_____________________________________________________________

Follow DNAexplain on Facebook, here.

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 your price but helps me 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.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research

Bennett Greenspan: Meet My Extended Family & Discover Extraordinary Deep Heritage

“My ancestors are in my soul. I can’t get them out of my mind.”

Bennett Greenspan

“And yes, I brake for cemeteries.”

Bennett Greenspan gave an incredibly interesting presentation at the 15th International Genetic Genealogy Conference held by FamilyTreeDNA in November 2023. Since his retirement in January 2021, he has been able to focus on his genealogy. Once a genealogist, always a genealogist.

Bennett said some things I hadn’t thought about, and now I’m viewing Y-DNA matches with a different perspective – based on how he’s using his results.

Ever since I met him, Bennett’s focus has been to use genetics to unravel his complex Jewish heritage.

The questions that drive Bennett are the same ones that motivate most genealogists:

  1. Who are we?
  2. Where did we come from?
  3. Where were we before we were there?
  4. How did my ancestors get there?

Bennett “lost his family lines” before the mid-1800s due to his Jewish heritage, exacerbated in the 1930s by the devastation wrought by the Holocaust. Families were either killed or scattered to survive. It has been through Y-DNA in particular that he has been able to establish unquestionable and confirmed connections with other Greenspan men, sometimes by similar but different surnames, like Green, and sometimes with other surnames entirely.

When Bennett first started down this path, he tested more than 62 men before actually finding one a decade later that matched his Y-DNA. Bennet commented that it was “a little frustrating.”

Persistence is the key, and sometimes, genealogy is a waiting game, but that’s small comfort to genealogists during that unproductive waiting period.

Eventually, Bennett reassembled his family, at least somewhat, but it was a long journey. Here’s Bennett’s incredible story, including surprises, as he tells it.

Bennett discovered genealogy at age 12 and, like many genealogists, created a pedigree chart by talking to his family.

I love the mark-outs. How many of us still have our first chart with its edits?

This is the young Bennett Greenspan, whose interest in genealogy would one day unlock secrets for all of us!

It was a long way from a decade with no matches to finding his genetic kin in Ukraine.

The Big Y-700 Time Tree shows Bennett’s lineage in Ukraine, but stepping back in time, some descendants of his ancestors are found in adjacent locations.

Bennett was passionately discussing his matches on the time tree and in the Greenspan project, so I visited the Greenspan DNA Project, where the earliest known ancestors of Bennett’s Big Y matches are shown on the Group Time Tree.

Bennett’s closest matches are shown as descendants of haplogroup J-ZS1718. He has additional matches who are not in the Greenspan project. Since this is the Group Time Tree, it only displays the people in that project, along with their earliest known ancestors, Isaac and Usher Greenspan.

12-Marker Matches

Bennett never fails to amaze me. He said something very important and profound about 12-marker matches that I really hadn’t thought about – at least not this way.

As a community, we are often guilty of discounting 12-marker matches, those that don’t match us at 25-markers or above, or with different surnames, as “too far back in time” or otherwise irrelevant. I always look at the names and earliest known ancestors of 12-marker matches, because that person may have tested back in the day when fewer markers were available. But if I don’t recognize something, I move on.

However, Bennett said that, ”Y-12 matches reach back to a common ancestor. 12-marker matches are not a quirk. They are related to you, just further back in time. You share a common ancestor with them, someplace. They may be more distant, but they are still your close matches.”

I’ve been in too much of a hurry for a quick win, and ignoring the (apparently not so) obvious.

Determining when and where their ancestors lived also paves the way to discover yours. Your Y-DNA and theirs were in the same place at the same time.

Of Bennett’s 171 12-marker matches, 107 have upgraded to the Big Y, probably mostly due to his encouragement. This benefits both them and Bennett by fleshing out the history of that entire group of men, including how they got to where they are found in the first available records. The Time Tree shows when Big Y testers shared a common ancestor, and based on Earliest Known Ancestor (EKA) locations, where. This provides further information about the lives of ancestors before contemporary records – in other words – people that we can never identify by name. It’s a window into ancestors before surnames.

Bennett notes that testers need to know their ancestral village or location to be most useful within the project, and of course, they need to enter their EKA information. Location information is how the Migration Map, Matches Map, and Discover tools, including the Time Tree, are built.

What Happened in Spain?

Bennett’s ancestors and those of his 12-marker matches are found in Spain, and as Bennett says, “One son stayed and one left about the year 296.”

While we have no idea of their names, based on the Time Tree combined with the cluster of earliest known ancestors, we know that they were in Spain, and when.

Their family story is revealed in the bifurcation of the tree found beneath haplogroup J-L823, formed about 296 CE. One line stayed in Spain, and Bennett’s line migrated to eastern Europe where that man’s descendants, including Bennett’s family, are found in the Russian Federation, Belarus, Poland, Lithuania, Sweden, Slovakia, Ukraine, Germany, Romania, the Czech Republic, and other eastern European locations. The closer to you in the tree and in time, the more relevant to your more recent ancestral story.

However, Bennett’s deeper ancestry, the migration of his ancestors to Spain, was only revealed by testing those more distantly related men. Those same men could well have been ignored entirely because they only matched at 12 markers.

According to Bennett, “Y-12 markers are important because these are the men most closely related to you in a database of 1 million men.”

How incredibly profound. How much have I been cavalierly overlooking?

How does this actually apply to Bennett’s results?

Bennett’s Spanish Matches

Bennett has the following STR panel matches who indicate that their EKA are from Spain. You can see that they match Bennett on a variety of panels.

  • X = yes, match
  • No = no match
  • Blank = not tested at that level.

In the Big Y GD column, the genetic distance (GD) is displayed as 15/660 where 15 is the number of mismatches, or the cumulative genetic distance ABOVE the 111 panel, and 660 is the number of STR markers above 111 with results.

The Big Y-500 test guaranteed a minimum of 500 total STR markers, and the Big Y-700 guarantees a minimum of 700 total STR markers, plus multiple scans of the balance of the Y chromosome for SNP mutations that define haplogroups. Testers don’t receive the same number of markers because the scan technology sometimes doesn’t read a specific location.

Tester 12 25 37 67 111 Big Y Test Big Y GD Big Y Match Haplogroup
AA X X X No No Yes 15/660 No J-FTD8826
DT X X No No X Yes 17/664 No J-FTE50318
JG X X No No
AR No No X X No No
ELR X X X No No
EL X X Yes 17/666 No J-FTE50318
GC X X X X No No
JC X No No
JLG X X No No No Yes 14/662 No J-FTE23540
MF X X No X No Yes 15/665 No J-FTD91126
MT X X X X No No
BE X X X X X Yes 20/664 No J-BY1795
DR X X X X X Yes 16/660 No J-FTC87344
EC X X X X X Yes 15/665 No J-FTC87344
GM X X No No No Yes 16/650 No J-FTD28153
GM X X X X No Yes 17/664 No J-FTD11019
LS X X No No No Yes 18/666 No J-FTD28153
NE X X X X X Yes 23/597 No J-BY1795
NC X No No
RR X X X No X Yes 22/659 No J-BY1795
TT X X X X X Yes 16/647 No J-FTC87344
XG X X X No No Yes 17/523 No J-BY167283
JA X X No No No Yes 15/646 No J-FTD11019

Of those 23 Spanish matches, sixteen have upgraded to Big Y tests, 14 of which are Big Y-700s, resulting in nine different haplogroups, all of which are descendants of Haplogroup J-L823. How cool is that?

The “Nos” in the Big Y Match Column aren’t mistakes. That’s right – none of these men match Bennett on the Big Y test, meaning they had more than a 30 mutation difference between them and Bennett on the Big Y test.

At first glance, you’d think that Bennett would have been disappointed, but that’s not the case at all! In fact, it was the information provided by these distant Spanish matches that provided Bennett with the information that his line had split sometime around the year 296 CE, with one branch remaining in Spain and his branch migrating to Eastern Europe, where he has lots of matches.

DNA Plus History

What was happening in Spain or the Iberian peninsula that involved the Jewish people about that time? Historical records exist of Jews living in that region before the fall of the Second Temple in about 70 CE, including records of Jews being expelled from Rome in 139 for their “corrupting influence.”

Furthermore, the Ancient DNA Connections for haplogroup J-L823, the most recent common ancestor (MRCA) for all of those branches, includes connections to multiple burials from:

  • Lebanon
  • Iran
  • Rome (from 1-400 CE)
  • Turkey
  • Jordan

Clearly, Bennett’s ancestor was in the Iberian peninsula around or before 296 CE. One branch stayed, winding up in Spain, and one headed for Europe.

Without these matches, some who didn’t match above the 12 or 25 marker level, how would Bennett have EVER known that his Jewish ancestors left the Middle East for Spain in the early years? How would he have known they migrated from Spain to Eastern Europe, and how would he have known that his line did not migrate directly from the Levant to Eastern Europe in the 9th century?

Big Y matches are typically within about 1500 years, but non-matches are still INCREDIBLY valuable. Without them, you can’t completely assemble your family story.

I noticed on the Time Tree that in Bennett’s Eastern European line, one of his ancestor’s brother lineages includes the Katzenellenbogen Rabbinic Lineage derived from ancient DNA samples.

Bennett’s successes have resulted from contacting his matches and encouraging upgrades. So how did he do it? What’s the magic sauce?

Contacting Matches

How to contact matches successfully is a question I see often. In fact, FamilyTreeDNA recently wrote about that in an article, here.

Bennett’s methodology for contacting his matches to encourage an upgrade is that he sends an email explaining why he’s encouraging them to upgrade, followed by a 2nd email three days later.

Bennett tells the recipient that we are at an inflection point in time. “It’s winter, the wind is blowing hard, and many of the leaves are gone.”

In other words, we need to cast the net wider and capture what we can, while we can. Unfortunately, many early testers have died, and with them, chapters of history are perishing.

Collaboration is key. In addition to encouraging upgrades, Bennett also offers Zoom calls to these groups of men to explain the results if they are interested.

What a GREAT idea! I need to begin offering that as well.

Upgrade Request

Bennett reaches out to his matches at various levels, but he expects his closer STR matches, meaning at the 67 and 111 marker level with the fewest mismatches, to match him on a Big Y-700 test and connect someplace between 300-600 years ago, which helps everyone flesh out their tree.

Bennett’s email:

Hello <name>,

Since you have already made a sizable investment in your Y-DNA, you now know that we come from the dominant male Middle Eastern group (Haplogroup J) of men who <subject here>.

What’s really neat is that our Y-DNA has recently been found in an archaeological site in Northwestern Jordan dated to about 4200 years ago. I know this because I upgraded to the Big Y, which tests SNPs, looking at several million locations on the Y chromosome of each man.

One academic customer recently compared this new technology as the difference between looking into space with binoculars versus the Hubble Telescope.

I don’t know if you are familiar with your list of matches at the highest level you’ve tested for, either Y-67 or Y-111. If you are, you should recognize my name and the names of others who have taken the Big Y test.

You’ll see what you’ll gain by letting me upgrade your test for you and determining whether you are related to my line – probably between about 200 years and 500 years.

This might be the second time that I have written to you on this matter; can I presume if I don’t hear from you that you’re not really interested in the Y-DNA subject anymore?

Can I run the test so that I can see how closely we are related – at my expense? (Of course, you get to see how closely related we are, too).

Please reply to me and say “yes.” You don’t even have to put a 🙂 if you don’t want to.

I started this company and this industry over 20 years ago. I predict that you will be happy with the history of YOU that this upgrade will uncover.

Best,

Bennett Greenspan

As you can see, this email can easily be personalized further and adapted to matches at the 37, 25, and 12 marker levels – or even Family Finder matches, now that intermediate-range haplogroups are being reported.

What’s Next?

I’m going back to every one of the kits I sponsored or that represent descendants of one of my ancestors to review their matches again – focusing not just on the closest matches with common surnames, but also on locations – and specifically at lower matching levels. I’ll also be checking their Family Finder matches for male surname matches, or similar surnames.

As is evident from Bennett’s tests, an entire mine of diamonds is out there, just waiting to be unearthed by a Big Y test.

And to think that some people have been advising people to ignore 12-marker matches out-of-hand because they are “entirely irrelevant.” They aren’t – for two reasons.

  1. First, some early testers only tested to that level
  2. Second, because of the deeper history that Big Y tests from those matches will uncover

You can view your Y-DNA matches, upgrade your own Y-DNA test, or order a Big Y-700 test if you haven’t yet tested by clicking here. What’s your next step?

_____________________________________________________________

Follow DNAexplain on Facebook, here.

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 your price but helps me 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.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research

FamilyTreeDNA 2023 Update – Past, Present and Future

At the FamilyTreeDNA International Conference on Genetic Genealogy, held November 3-5 in Houston for group project administrators, product and feature updates were scattered across both days in various presentations.

I’ve combined the updates from FamilyTreeDNA into one article.

I’ve already written two articles that pertain to the conference.

FamilyTreeDNA has already begun rolling the new Y DNA haplogroups from Family Finder autosomal tests, which I wrote about here:

I still have at least two more articles to publish from this conference that was chocked full of wonderful information from a wide range of talented speakers.

Past, Present, and Future with Katy Rowe-Schurwanz

Katy Rowe-Schurwanz, FamilyTreeDNA’s Product Manager, provided an update on what has been accomplished in the four and a half years since the last conference, what’s underway now, and her wish list for 2024.

Please note the word “wish list.” Wish list items are NOT commitments.

Recent Milestones

A lot has been happening at FamilyTreeDNA since the last conference.

Acquisition and Wellness Bundles

As everyone is aware, at the end of 2020, myDNA acquired Gene by Gene, the parent company of FamilyTreeDNA, which included the lab. As a result, the FamilyTreeDNA product menu has expanded, and wellness bundles are now available for FamilyTreeDNA customers.

If you’re interested, you can order the Wellness product in a bundle with a Family Finder test, here.

You can add the Wellness product for $39 if you’ve already tested.

New TIP (Time Prediction) STR Report

Did you notice that the old TIP report for Y DNA STR markers was replaced with an updated version several months ago?

To view the new report, sign on and select your Y DNA matches. At the far right of each match you’ll see these three icons representing a pedigree chart, notes, and the TIP (Time Predictor) report.

The updated TIP report includes wonderful new graphs and age estimates for each match category, which you can read about, here. Each category, such as 67-marker matches, has time estimates in which a common ancestor might have lived at each possible genetic distance.

Math is our friend, and thankfully, someone else has done it for us!

Please note that the Big Y SNP dates are MUCH more accurate for a variety of reasons, not limited to the instability and rapid mutation rate of STR mutations.

MyOrigins3

MyOrigins3, FamilyTreeDNA’s ethnicity offering, added over 60 new reference populations for a total of 90, plus chromosome painting. You can read about MyOrigins features here, and the white paper, here.

This is one of my favorite improvements because it allows me to identify the segment location of my population ancestries, which in turn allows me to identify people who share my minority segments such as Native American and African.

Due to a lack of records, these relationships are often exceedingly difficult to identify, and MyOrigins3 helps immensely.

Additional Releases

Additional products and features released since the last conference include:

Discover

Released in July 2022, Discover is the amazing new free product that details your ancestor’s Y DNA “story” and his walk through time and across the globe.

In the past 18 months, all of the Discover features are new, so I’m only making a brief list here. The great thing is that everyone can use Discover if you know or can discover (pardon the pun) the haplogroup of your ancestral lines. Surname projects are often beneficial for finding your lineages.

  • Haplogroup Story includes haplogroup location, ages derived from the earliest known ancestor (EKA) of your matches, and ancient DNA samples. Please be sure you’ve entered or updated your EKA, and that the information is current. You can find instructions for how to update or add your EKA here.
  • A recent addition to the haplogroup story includes Haplogroup Badges.
  • Country Frequency showing where this haplogroup is found with either a table view or an interactive map
  • Famous and infamous Notable Connections, including Mayflower passengers, Patriots from the American Revolution, US presidents, royal houses, artists, musicians, authors, pirates, sports figures, scientists, and more.

If you know of a proven connection to a notable figure, contact customer support and let them know! Notable connections are added every week.

One famous Discover connection is Ludwig von Beethoven which resulted from a joint academic study between FamilyTreeDNA and academic researchers. It’s quite a story and includes both a mystery and misattributed parentage. You can see if you match on Discover and read about the study, here.

  • Updated Migration Map, including locations of select ancient DNA sites
  • The Time Tree, probably the most popular Discover report, shows the most current version of the Y DNA phylotree, updated weekly, plus scientifically calculated ages for each branch. Tree node locations are determined by your matches and their EKA countries of origin. I wrote about the Time Tree, here.
  • Anticipated in early 2024, the EKA and block tree matches will also be shown on the Time Tree in Discover for individual Big Y testers, meaning they will need to sign in through their kits.
  • The Group Time Tree, visible through group projects, takes the Time Tree a step further by including the names of the EKA of each person on the Time Tree within a specific project. Information is only displayed for project members who have given permission to include their data. You can select specific project groupings to view, or the entire project. I wrote about the Group Time Tree here and here.
  • Globetrekker is an exclusive Big Y mapping feature discussed here, here, here, and here.
  • Ancient Connections includes more than 6,100 ancient Y DNA results from across the globe, which have been individually analyzed and added for matching in Discover. Ancient Connections serve to anchor haplogroups and provide important clues about matches, migration paths and culture. New connections are added weekly or as academic papers with adequate Y DNA coverage are released.
  • Your Ancestral Path, which lists the haplogroups through every step from the tester back to Y Adam and beyond. Additional information for each haplogroup in your path includes “Time Passed” between haplogroups, and “Immediate Descendants,” meaning haplogroups that descend from each subclade. New columns recently added include “Tested Modern Descendants” and “Ancient Connections.”
  • Suggested Projects include surname, haplogroup, and geographic projects. Katy said that people joining projects are more likely to collaborate and upgrade their tests. You can also see which projects other men with this haplogroup have joined, which may well be projects you want to join too.
  • Scientific Details provides additional information, such as each branch’s confidence intervals and equivalent variables (SNPs). You can read more here.
  • Compare Haplogroups is the most recent new feature, added just last month, which allows you to enter any two haplogroups and compare them to determine their most recent common ancestral haplogroup. You can read about Compare Haplogroups, here.

Please note that the Studies feature is coming soon, providing information about studies whose data has been included in Discover.

You can read about Discover here, here, here, and here.

If you’re interested, FamilyTreeDNA has released a one-minute introduction to Y DNA and Discover that would interest new testers, here.

Earliest Known Ancestor (EKA) Improvement

Another improvement is that the earliest known ancestor is MUCH easier to enter now, and the process has been simplified. The EKAs are critical for Discover, so PLEASE be sure you’ve entered and updated your EKA.

Under the dropdown beside your name in the upper right-hand corner of your personal page, select Account Settings, then Genealogy and Earliest Known Ancestors. Complete the information, then click on “Update Location” to find or enter the location on a map to record the coordinates.

It’s easy. Just type or drop a pin and “Save.”

Saving will take you back to the original EKA page. Save that page, too.

Recommended Projects on Haplogroups & SNPs Page

You’re probably aware that Discover suggests projects for Y DNA testers to join, but recommended haplogroup projects are available on each tester’s pages, under the Y DNA Haplotree & SNPs page, in the Y DNA STR results section.

If there isn’t a project for your immediate haplogroup, just scroll up to find the closest upstream project. You can also view this page by Variants, Surnames and Countries.

This is a super easy tool to use to view which surnames are clustered with and upstream of your haplogroup. With Family Finder haplogroups being assigned now, I check my upstream haplogroups almost daily to see what has been added.

For example, my Big Y Estes results are ten branches below R-DF49, but several men, including Estes testers, have been assigned at this level, thanks to Y DNA haplogroups from Family Finder testing. I can now look for these haplogroups in the STR and Family Finder matches lists and see if those men are receptive to Big Y testing.

Abandoned Projects

Sometimes group project administrators can no longer function in that capacity, resulting in the project becoming abandoned. FamilyTreeDNA has implemented a feature to help remedy that situation.

If you discover an abandoned project, you can adopt the project, spruce things up, and select the new project settings. Furthermore, administrators can choose to display this message to recruit co-administrators. I need to do this for several projects where I have no co-admin.

If you are looking for help with your project, you can choose to display the button
through the Project Profile page in GAP. For non-project administrators, if you’d like to help, please email the current project administrators.

New Kit Manager Feature

FamilyTreeDNA has added a “Kit Manager” feature so that an individual can designate another person as the manager of their kit.

This new setting provides an avenue for you to designate someone else as the manager of your DNA test. This alerts FamilyTreeDNA that they can share information with both of you – essentially treating your designated kit manager the same as you.

If you’re the kit manager for someone else, you NEED to be sure this is completed. If that person is unavailable for some reason, and support needs to verify that you have legitimate access to this kit, this form and the Beneficiary form are the ONLY ways they can do that.

If your family member has simply given you their kit number and password, and for some reason, a password reset is required, and their email address is the primary contact – you may be shut out of this kit if you don’t complete this form.

Beneficiary Page

Additionally, everyone needs to be sure to complete the Beneficiary page so that in the event of your demise, FamilyTreeDNA knows who you’ve designated to access and manage your DNA account in perpetuity. If you’ve inherited a kit, you need to add a beneficiary to take over in the event of your death as well.

What is FamilyTreeDNA working on now?

Currently in the Works

Katy moved on to what’s currently underway.

Privacy and Security

Clearly, the unauthorized customer data exposure breach at 23andMe has reverberated through the entire online community, not just genetic genealogy. You can read about the incident here, here, here, and here.

FamilyTreeDNA has already taken several steps, and others are in development and will be released shortly.

Clearly, in this fast-moving situation, everything is subject to change.

Here’s what has happened and is currently planned as of today:

  • Group Project Administrators will be required to reset their password soon.

Why is this necessary?

Unauthorized access was gained to 23andMe accounts by people using the same password for multiple accounts, combined with their email as their user ID. Many people use the same password for every account so that they can remember it. That means that all a hacker needs to do is breach one account, and they can use that same information to “legitimately” sign in to other accounts. There is no way for the vendor to recognize this as unauthorized since they have both your user ID and password.

That’s exactly what happened at 23andMe. In other breaches, this information was exposed, and hackers simply tried the same username and password combination at 23andMe, exposing the entire account of the person whose account they signed in “as.” This includes all of their matches, genetic tree, shared matches, matches of matches, ethnicity, and segments. They could also have downloaded both the match list and the raw DNA file of the compromised account.

At FamilyTreeDNA, project administrators can select their own username, which could be their email, so they will be required to reset their password.

Additional precautions have been put in place on an interim basis:

  • A pause in the ability to download match and segment information.
  • A pause in accepting 23andMe uploads.

Administrators will also be required to use two-factor authentication (2FA.) To date, two of the four major vendors are requiring 2FA. I would not be surprised to see it more broadly. Facebook recently required me to implement 2FA there, too, due to the “reach” of my postings, but 2FA is not required of everyone on Facebook.

Please note that if you received an email or message that is supposedly from any vendor requiring 2FA, GO DIRECTLY TO THAT VENDOR SITE AND SIGN IN.  Never click on a link in an email you weren’t expecting. Bad actors exploit everything.

Customers who are not signing in as administrators are not required to implement 2FA, nor will they be required to reset their password.

Personally, I will implement 2FA as soon as it’s available.

While 2FA is an extra step, it’s easy to get used to, and it has already literally saved one of my friends from an authorized hack on their primary and backup email accounts this week. Another friend just lost their entire account on Facebook because someone signed in as them. Their account was gone within 15 minutes.

2FA is one of those things you don’t appreciate (at all) until it saves you, and then, suddenly, you’re incredibly grateful.

At this point in time, FamilyTreeDNA users will NOT be required to do a password reset or implement 2FA. This is because customers use a kit number for sign-in and not a username or email address. I would strongly recommend changing your password to something “not easy.” Never reuse passwords between accounts.

I really, really want you to visit this link at TechRepublic and scroll down to Figure A, which shows how long it takes a hacker to crack your password. I guarantee you, it’s MUCH quicker than you’d ever expect.

Kim Komando wrote about this topic two years ago, so compare the two charts to see how much easier this has become in just two years.

Again, if you receive an email about resetting your password, don’t click on a link. Sign in independently to the vendor’s system, but DO reset your password.

FamilyTreeDNA also engages in additional security efforts, such as ongoing penetration testing.

New Permissions

Additionally, at FamilyTreeDNA, changes were already in the works to separate out at least two permissions that testers can opt-in to without granting project administrators Advanced rights.

  • Download data
  • Purchase tests

The ability to purchase tests can be very important because it allows administrators to order and pay for tests or upgrades on behalf of this tester anytime in the future.

Family Finder Haplogroups

FamilyTreeDNA has already begun releasing mid-level Y DNA haplogroups for autosomal testers in a staggered rollout of several thousand a day.

I wrote about this in the article, FamilyTreeDNA Provides Y DNA Haplogroups from Family Finder Autosomal Tests, so I’m not repeating all of that information here – just highlights.

  • The Family Finder haplogroup rollout is being staggered and began with customers on the most recent version of the testing chip, which was implemented in March of 2019.
  • Last will be transfers/uploads from third parties.
  • Haplogroups resulting from tests performed in the FTDNA labs will be visible to matches and within projects. They will also be used in both Discover and the haplotree statistics. This includes Family Finder plus MyHeritage and Vitagene uploads.
  • Both MyHeritage and Vitagene are uploaded or “transferred” via an intracompany secure link, meaning FamilyTreeDNA knows that their information is credible and has not been manipulated.
  • Haplogroups derived from tests performed elsewhere will only be visible to the user or a group administrator viewing a kit within a project. They will not be visible to matches or used in trees or for statistics.
  • Any man who has taken a Y DNA STR test will receive a SNP-confirmed, updated haplogroup from their Family Finder test that replaces their predicted haplogroup from the STR test.

Please read this article for more information.

New Discover Tools and Updates

Discover content continues to be updated, and new features are added regularly, creating an increasingly robust user experience.

Soon, group administrators will be able to view all Discover features (like Globetrekker) when viewing kits of project members who have granted an appropriate level of access.

Ancient and Notable connects are added weekly, and a new feature, Study Connections, will be added shortly.

Study Connections is a feature requested by customers that will show you which study your academic matches came from. Today, those results are used in the Y DNA tree, but the source is not detailed.

Anticipated in early 2024, the EKA and block tree matches will also be shown on the Time Tree in Discover for individual Big Y testers (not publicly).

Big Y FaceBook Group

FamilyTreeDNA has ramped up its social media presence. They launched the Big Y Facebook group in July 2023, here, which currently has just under 9000 members. Several project administrators have volunteered their time to help manage the group.

FamilyTreeDNA Blog

In addition, FamilyTreeDNA is publishing at least one blog article each week, and sometimes more. You can view or subscribe here. Some articles are written by FamilyTreeDNA staff, but project administrators and customers author other content.

Multi-Language Support

Translation of the main FamilyTreeDNA website and results pages to Spanish has begun, with more languages planned soon.

Paypal, Payments, and Gift Cards

Paypal has been added as a payment selection, along with a PayPal option that provides the ability to make payments.

Additionally, a gift card can be purchased from the main page.

Million Mito Project & Mitotree

Work on the Million Mito Project is ongoing.

The Million Mito Project was launched in 2020 as a collaborative effort between FamilyTreeDNA’s Research & Development Team and the scientific portion of the Genographic Project. I’m a team member and wrote about the Million Mito Project, here.

We’re picking up from where the Phylotree left off in 2016, analyzing 20 times more mtDNA full sequences and reimagining the mtDNA Haplotree. By examining more mtDNA data and applying the processes that allowed FamilyTreeDNA to build the world’s largest Y DNA Haplotree, we can also create the world’s largest Mitotree.

In 2022, the first update was released, authored by the Million Mito team, with the discovery of haplogroup L7. You can read about this amazing discovery rooted deep in the tree here, here, and here. (Full disclosure: I’m a co-author.)

Not only that, but “Nature Scientific Reports” selected this article as one of five named Editor’s Choice in the Mitogenomics category, here. In the science world, that’s a HUGE deal – like the genetic Emmy.

Here’s one example of the type of improvements that can be expected. Currently, the formation of haplogroup U5a2b2a reaches back to about 5000 years ago, but after reanalysis, current branches originated between 500 and 2,500 years ago, and testers are clustered more closely together.

This is SOOO exciting!!!

Just as Discover for Y DNA results was built one feature at a time, the same will be true for MitoDiscover. That’s my name, not theirs.

As the new Mitotree is rolled out, the user interface will also be updated, and matching will function somewhat differently. Specifically, it’s expected that many more haplogroups will be named, so today’s matching that requires an exact haplogroup match to be a full sequence match will no longer work. That and other matching adjustments will need to be made.

I can hardly wait. I have so many results I need to be able to view in a tree format and to place in a timeframe.

You can be included in this exciting project, learn more about your matrilineal (mother’s) line, and hopefully break down some of those brick walls by taking the full sequence mitochondrial DNA test, here.

After the new Mitotree is rolled out and the Y DNA Family Finder haplogroups are completed, Family Finder customers, where possible, will also receive at least a basic-level mitochondrial haplogroup. Not all upload files from other vendors include mtDNA SNPs in their autosomal files. The mitochondrial Family Finder haplogroup feature isn’t expected until sometime in 2025, after the new tree and MitoDiscover are complete.

The Future

What’s coming later in 2024, or is ongoing?

Privacy Laws

Most people aren’t aware of the new privacy laws in various states, each of which has to be evaluated and complied with.

The effects of these changes will be felt in various areas as they are implemented.

New Kits Opted Out of IGG

Since late August, all new FTDNA kits are automatically opted OUT of Investigative Genetic Genealogy (IGG) by default.

Regular matching consent and IGG matching consent have been separated during onboarding.

Biobanking Separate Consent

Another consent change is to have your sample biobanked. FamilyTreeDNA has always maintained your sample for “roughly 25 years.” You could always ask to have your sample destroyed, but going forward, you will be asked initially if you want your sample to be retained (biobanked.) It’s still free.

Remember, if someone declines the biobanking option, their DNA will be disposed of after testing. They can’t order upgrades without submitting a new sample. Neither can their family after they’re gone. I ordered my mother’s Family Finder test many years after she had gone on to meet our ancestors – and I’m incredibly grateful every single day.

MyHeritage Tree Integration

An exciting change coming next year is tree integration with MyHeritage.

And no, before any rumors get started, FAMILYTREEDNA IS NOT MERGING WITH MYHERITAGE. It’s a beneficial marriage of convenience for both parties.

In essence, one of the primary focuses of MyHeritage is trees, and they do that very well. FamilyTreeDNA is focused on DNA testing and their existing trees have had issues for years. MyHeritage trees are excellent, support pedigree collapse, provide search capabilities that are NOT case sensitive, SmartMatching, and much more.

If you don’t have a MyHeritage account, creating one is free, and you will be able to either port your existing FamilyTreeDNA tree, or begin one there. If you’re already a MyHeritage member, FamilyTreeDNA and MyHeritage are planning together for a smooth integration for you. More detailed information will be forthcoming as the integration progressed and is released to customers.

You’ll be able to connect multiple kits to your tree at MyHeritage, just like you can at FamilyTreeDNA today, which enables family matching, aka bucketing.

You can also have an unlimited number of different trees at MyHeritage on the same account. You’re not limited to one.

After you link your initial FamilyTreeDNA kit to the proper person in your MyHeritage tree, you’ll be able to relink any currently linked kits.

MyHeritage will NOT receive any DNA information or match information from FamilyTreeDNA, and yes, you’ll be able to use the same tree independently at MyHeritage for their DNA matching.

You’ll still be able to view your matches’ trees, except it will actually be the MyHeritage tree that will be opened at FamilyTreeDNA in a new tab.

To the best of my knowledge, this is a win-win-win, and customers of both companies aren’t losing anything.

One concern is that some FamilyTreeDNA testers have passed away and cannot transition their tree, so a view-only copy of their tree will remain at FamilyTreeDNA so that their matches can still see their tree.

Big Y Infrastructure

Katy mentioned that internal discussions are taking place to see what changes could be made to improve things like matching and test processing times.

No changes are planned for SNP or STR coverage, but discussions are taking place about a potential update to the Telomere to Telomere (T2T) reference. No promises about if or when this might occur. The last part of the human genome to be fully sequenced, the T2T reference model includes the notoriously messy and unreliable region of the Y chromosome with many repeats, duplications, gaps, and deletions. Some data from this region is probably salvageable but has previously been omitted due to the inherent problems.

I’m not sure this shouldn’t be in the next section, the Wishlist.

Wishlist

There are lots of good things on the Wishlist – all of which I’d love.

I’d have difficulty prioritizing, but I’d really appreciate some Family Finder features in addition to the items already discussed. I’d also like to see some GAP (administrator) tool updates.

Which items do you want to see most?

Katy said that FamilyTreeDNA is NOT planning to offer a Whole Genome Sequencing (WGS) test anytime soon. So, if you’re holding your breath, please don’t. Based on what Katy did say, WGS is very clearly not a consideration in 2024 and I don’t expect to see it in 2025 either unless something changes drastically in terms of technology AND pricing.

While WGS prices have come down, those consumer tests are NOT scanned at the depth and quality required for advanced tests like the Big Y or even Family Finder. Normally consumer-grade WGS tests are scanned between 2 and 10 times, where the FamilyTreeDNA lab scans up to 30 times in order to obtain a quality read. 30X scans are in the same category as medical or clinical grade whole genome scans. Significantly higher quality scans mean significantly higher prices, too, so WGS isn’t ready for genealogy prime time yet.

Additionally, commercially available WGS tests are returned to the customer “as is,” and you’re left to extract the relevant SNPs and arrange them into files, or find someone else to do that. Not to mention, in order to preserve the integrity of their database, FamilyTreeDNA does not accept Y or mitochondrial DNA uploads.

Recently, I saw two WGS files with a 20-25% no-call rate for the autosomal SNPs required for the Family Finder test. Needless to say, that’s completely unacceptable. Some tools attempt to “fix” that mess by filling in the blanks in the format of either a 23andMe or Ancestry file so you can upload to vendors, but that means you’re receiving VERY unreliable matches.

The reason none of the major four vendors offer WGS testing for genealogists is because it’s not financially feasible nor technologically beneficial. The raw data file alone won’t fit on most home computers. WGS is just not soup yet, and it won’t be for the general consuming public, including relevant tools, for at least a few years.

I’ve had my whole genome sequenced, and trust me, I wish it were feasible now, but it just isn’t.

Suggestions Welcomed

Katy said that if you have suggestions for items NOT on the wishlist today to contact her through support.

I would add that if you wish to emphasize any specific feature or need above others, please send that feedback, politely, to support as well.

Katy ended by thanking the various teams and individuals whose joint efforts together produce the products we use and enjoy today.

Lab Update

Normally, DNA testing companies don’t provide lab updates, but this conference is focused on group project administrators, who are often the most dedicated to DNA testing.

A lab update has become a tradition over the years.

Linda Jones, Lab Manager, provided a lab update.

You may or may not know that the FamilyTreeDNA lab shifted gears and stepped up to handle Covid testing.

Supply-chain shortages interfered, but the lab ran 24×7 between 2020 and 2022.

Today, the lab continues to make improvements to processes with the goal of delivering the highest quality results in a timely manner.

On Monday, after the conference, attendees could sign up for a lab tour. You might say we are a rather geeky bunch and really enjoy the science behind the scenes.

Q&A and Thank You

At the end of the conference, the FamilyTreeDNA management team answered questions from attendees.

Left to right, Daniel Au, CTO; Linda Jones, Lab Manager; Katy Rowe-Schurwanz, Product Manager; Clayton Conder, VP Marketing; Goran Runfeldt, Head of R&D; and Andrew Gefre, Development Manager. Not pictured, Jeremy Balkin, Support Manager; Kelly Jenkins, VP of Operations; and Janine Cloud, Group Projects Manager. Janine is also responsible for conferences and events, without whom there would have been no 2023 FamilyTreeDNA conference. Janine, I can’t thank you enough!

A huge thanks to all of these people and many others, including the presenters, CSRs,  IT, and other FamilyTreeDNA team members for their support during the conference, enabling us to enjoy the conference and replenish the well of knowledge.

_____________________________________________________________

Follow DNAexplain on Facebook, here.

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 your price but helps me 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.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research

Reminder – Free Discover Webinar Through September 5th

Wow – has this ever been a week!!! This article should be subtitled, “Never Argue With a Woman Named Idalia.” Trust me, Idalia will be the least popular baby name for 2023.

But first things first.

I want to provide a friendly reminder that the webinar, Y-DNA Discover Tool – What News Can Your Haplogroup Reveal? is free through September 5th at Legacy Family Tree Webinars and will be available in their library for subscribers thereafter.

Discover is a free Y-DNA tool provided by FamilyTreeDNA.

Anyone can use Discover. You don’t need to have taken a Y-DNA test, but the greatest benefit will be realized with Big Y-700 test results. Don’t worry about that now, though, because I explain the differences between tests in the webinar. You can get a lot out of Discover, even if you only know a base-level haplogroup.

Normally, these webinars are live, but those plans were interrupted by Hurricane Idalia.

Idalia developed so quickly – and we really weren’t sure where it was going until just a day or so in advance – or how severe it would be. It was ugly, and as I write this, Idalia is still torturing the east coast.

When I realized the possible impact, and that the probability of having both power and internet were very remote, I contacted Legacy Family Tree Webinars and discussed options.

We really didn’t want to reschedule since more than 2000 people from around the world had signed up for the webinar. We decided that the best option was to record the webinar in advance as a precaution. Then, if possible and Idalia targeted her wrath elsewhere, I would still give it live.

Needless to say, doing anything live wasn’t in the cards on Wednesday. I should add that I am safe and dry with minimal damage – just some branches and small trees down – but others nearby aren’t nearly so fortunate. Flooding was recorded in feet of water, roads are still closed to vehicles, boats rescuing people who didn’t evacuate are zipping down the flooded streets in many places, and there’s just a massive mess. Thousands of people are displaced.

However, as they say, “the show must go on,” and it did. The webinar was presented even though I couldn’t be there for Q&A. Anticipating that possibility, I recorded a lot of detail for you.

I hope I didn’t sound as rattled as I felt, because I was recording in the midst of hurricane prep and the first bands of wind and rain were already lashing the windows. I knew that we were facing a monster storm. That’s very unsettling.. All things considered, I think the webinar went quite well. I was afraid the power would go out while we were recording, but fortunately, it didn’t.

At the end of the webinar, I pulled everything from all of the Discover tools, the Block Tree, and the Group Time Tree together, then added historical migration records along with known, proven family genealogy.

Given that:

  • How did Discover do?
  • Was it useful?
  • Is it accurate?
  • How accurate?
  • What has it done for the Estes paternal line genealogy?
  • What do I know about my Estes lineage that I didn’t know before?
  • What’s the next step?
  • What can Discover do for you?

I really encourage you to tune in and take advantage of this free educational webinar through September 5th, maybe even over the Labor Day weekend.

Please feel free to share this article and information about the webinar with interested groups and organizations!!!

_____________________________________________________________

Follow DNAexplain on Facebook, here.

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.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research

Y-DNA Discover Tool – Free Webinar

You’re invited to join me for a free, live webinar about the Y-DNA Discover tool on Wednesday, August 30th, at 2 PM EDT, courtesy of Legacy Family Tree Webinars.

FamilyTreeDNA‘s Discover tool can be used with any Y-DNA haplogroup. I’ve written about Discover here and the newest feature, Globetrekker, here

Y-DNA Discover Tool – What News Can Your Haplogroup Reveal? will be free next Wednesday and for the following seven days. After that, this webinar, along with the rest of Legacy Family Tree’s extensive webinar library is available via an annual subscription of $49.95. I think my new webinar will be webinar number 2042 in their library.

A subscription also provides access to the webinar handouts, the webinar chat logs, and a subscribers-only door prize during each webinar. If you’re interested, you can subscribe here.

What’s In the Discover Webinar?

Discover is an amazing tool, but I think many people are missing ways to use it for genealogy. I’ll cover both the free Discover version and the additional functionality for Big Y testers.

Everyone can use Discover for any Y-DNA haplogroup, no matter the haplogroup source. Of course, the more granular or refined the haplogroup, the more relevant the haplogroup will be to your most recent ancestors. Y-DNA haplogroups are available through the following types of tests:

  • Autosomal at 23andMe, LivingDNA – base or midrange level haplogroup derived from target testing a few Y-DNA locations in an autosomal test. These haplogroups are generally at least a few thousand years old. Think tree branches.
  • Haplogroup estimate when taking the 12, 25, 37, 67, or 111 STR marker Y-DNA tests at FamilyTreeDNA. Think tree branches.
  • The Big-Y DNA test, also at FamilyTreeDNA, provides the most refined and detailed haplogroup. Think twigs and leaves that are very specific to your family at the ends of each larger branch.

After briefly introducing Y-DNA, how it works, and why you care, I’ll be stepping through each Discover feature and function. This includes the Group Time Tree, which isn’t part of Discover but is available through FamilyTreeDNA‘s projects and uses the Discover technology.

  • Haplogroup story – description and overview
  • Country Frequency – where this haplogroup and related haplogroups are found in the world
  • Notable Connections – the famous and infamous, and what that means to you
  • Migration Map –  short story, complete with ancient DNA sites
  • Globetrekker – animated, refined story with lots of detail and several options. Paths your ancestors may have taken to arrive where your line is first found.
  • Ancient Connections – ancient Y-DNA that anchors haplogroups
  • Time Tree – when and where haplogroups were born and how they connect
  • Ancestral Path – every step from you to Y-Adam, when and where that step occurred
  • Suggested Projects – relevant projects for collaboration (and buried hints)
  • Scientific Details –  haplogroup age estimates, age ranges, and your haplogroup’s mutations
  • Group Time Tree – for project members only – the Time Tree complete with all Big-Y testers who’ve opted-in to this project and provided a location, plus earliest known ancestors, displayed in groups
  • What you can do to help yourself

I’ll discuss using the various Discover features to understand what the information means to you, why it’s important, and how to utilize it for your genealogy. I’ll also talk about how to incorporate Block Tree information and projects.

If you’d like to listen and educate yourself, that’s great, but you might want to take this opportunity to think of a male-line brick wall you’d like to work on or learn more about. Don’t we all want to know more about every line – even if we’ve run out of known ancestors and records? Keep your focus line in mind as we apply the tools one-by-one to my Estes lineage, building evidence, during the webinar. Discover helps us peel back the veil of time.

At the end, I’ll provide hints and tips about constructing your plan of attack – how to locate testers and what to do next.

Mark your calendar, and don’t forget to convert the time to where you live. Next Wednesday, August 30, at 2 EDT. See you then!!

_____________________________________________________________

Follow DNAexplain on Facebook, here.

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.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research

What Is a Sibling Anyway? Full, Half, Three-Quarters, Step, Adopted, Donor-Conceived & Twins

I’ve seen the term sibling used many different ways, sometimes incorrectly.

When referring to their own siblings, people usually use the term brother or sister, regardless of whether they are talking about a full, half or step-sibling. It’s a term of heart or description. It’s often genealogists who are focused on which type of sibling. As far as I’m concerned, my brother is my brother, regardless of which type of brother. But in terms of genetics, and genealogy, there’s a huge difference. How we feel about our sibling(s) and how we are biologically related are two different things.

Let’s cover the various types of siblingship and how to determine which type is which.

  • Full Siblings – Share both parents
  • Half-Siblings – Share only one parent
  • Three-Quarter Siblings – It’s complicated
  • Adopted Siblings
  • Donor-Conceived
  • Step-Siblings – Share no biological parent
  • Twins – Fraternal and Identical

Full Siblings

Full siblings share both parents and share approximately 50% of their DNA with each other.

You can tell if you are full siblings with a match in various ways.

  1. You share the same fairly close matches on both parents’ sides. For example, aunts or uncles or their descendants.

Why do I say close matches? You could share one parent and another more distant relative on the other parent’s side. Matching with close relatives like aunts, uncles or first cousins at the appropriate level is an excellent indicator unless your parents or grandparents are available for testing. If you are comparing to grandparents, be sure to confirm matches to BOTH grandparents on each side.

  1. Full siblings will share in the ballpark of 2600 cM, according to DNAPainter’s Shared cM Tool.

Keep in mind that you can share more or less DNA, hence the range. It’s also worth noting that some people who reported themselves as full siblings in the Shared cM project were probably half siblings and didn’t realize it.

  1. Full siblings will share a significant amount of fully identical regions (FIR) of DNA with each other, meaning they share DNA at the same DNA address from both parents, as illustrated above. Shared DNA with each other inherited from Mom and Dad are blocked in green. The fully identical regions, shared with both parents, are bracketed in purple. You can’t make this determination at FamilyTreeDNA, MyHeritage or Ancestry, but you can at both 23andMe and GEDmatch.

At GEDmatch, the large fully green areas in the chromosome browser “graphics and positions” display indicates full siblings, where DNA is shared from both parents at that location.

I wrote about the details of how to view fully identical regions (FIR) versus half identical regions (HIR) in the article, DNA: In Search of…Full and Half-Siblings.

  1. If your parents/grandparents have tested, you and your full sibling will both match both parents/grandparents. Yes, I know this sounds intuitive, but sometimes it’s easy to miss the obvious.

At FamilyTreeDNA, you can use the matrix tool to see who matches each other in a group of people that you can select. In this case, both siblings are compared to the father, but if the father isn’t available, a close paternal relative could substitute. Remember that all people who are 2nd cousins or closer will match.

  1. At Ancestry, full siblings will be identified as either “brother” or “sister,” while half-siblings do not indicate siblingship. Half-siblings are called “close family” and a range of possible relationships is given. Yes, Ancestry, is looking under the hood at FIR/HIR regions. I have never seen a full sibling misidentified as anything else at Ancestry. Unfortunately, Ancestry does not give customers access to their matching chromosome segment location data.
  2. Y-DNA of males who are full siblings will match but may have some slight differences. Y-DNA alone cannot prove a specific relationship, with very rare exceptions, but can easily disprove a relationship if two males do not match. Y-DNA should be used in conjunction with autosomal DNA for specific relationship prediction when Y-DNA matches.
  3. Y-DNA testing is available only through FamilyTreeDNA, but high-level haplogroup-only estimates are available through 23andMe. Widely divergent haplogroups, such as E versus R, can be considered a confirmed non-match. Different haplogroups within the same base haplogroup, such as R, but obtained from different vendors or different testing levels may still be a match if they test at the Big Y-700 level at FamilyTreeDNA.
  4. Mitochondrial DNA, inherited matrilineally from the mother, will match for full siblings (barring unusual mutations such as heteroplasmies) but cannot be used in relationship verification other than to confirm nonmatches. For both Y-DNA and mitochondrial DNA, it’s possible to have a lineage match that is not the result of a direct parental relationship.
  5. Mitochondrial DNA testing is available only through FamilyTreeDNA, but haplogroup-only estimates are included at 23andMe. Different base haplogroups such as H and J can be considered a non-match.
  6. A difference in ethnicity is NOT a reliable indicator of half versus full siblings.

Half-Siblings

Half-siblings share only one parent, but not both, and usually share about 25% of their DNA with each other.

You will share as much DNA with a half-sibling as you do some other close matches, so it’s not always possible for DNA testing companies to determine the exact relationship.

Referencing the MyHeritage cM Explainer tool, you can see that people who share 1700 cM of DNA could be related in several ways. I wrote about using the cM Explainer tool here.

Hints that you are only half-siblings include:

  1. At testing vendors, including Ancestry, a half-sibling will not be identified as a sibling but as another type of close match.
  2. If your parents or grandparents have tested, you will only match one parent or one set of grandparents or their descendants.
  3. You will not have shared matches on one parent’s side. If you know that specific, close relatives have tested on one parent’s side, and you don’t match them, but your other family members do, that’s a very big hint. Please note that you need more than one reference point, because it’s always possible that the other person has an unknown parentage situation.
  4. At 23andMe, you will not show fully identical regions (FIR).
  5. At GEDmatch, you will show only very minimal FIR.

Scattered, very small green FIR locations are normal based on random recombination. Long runs of green indicate that significant amounts of DNA was inherited from both parents. The example above is from half-siblings.

  1. At FamilyTreeDNA and 23andMe, most men who share a mother will also share an X chromosome match since men only inherit their X chromosome from their mother. However, it is possible for the mother to give one son her entire X chromosome from her father, and give the other son her entire X chromosome from her mother. Therefore, two men who do share a mother but don’t have an X chromosome match could still be siblings. The X is not an entirely reliable relationship predictor. However, if two men share an entire X chromosome match, it’s very likely that they are siblings on their mother’s side, or that their mothers are very close relatives.

Three-Quarter Siblings

This gets a little more complicated.

Three-quarter siblings occur when one parent is the same, and the other parents are siblings to each other.

Let’s use a real-life example.

A couple marries and has children. The mother dies, and the father marries the mother’s sister and has additional children. Those children are actually less than full siblings, but more than half-siblings.

Conversely, a woman has children by two brothers and those children are three-quarter siblings.

These were common situations in earlier times when a man needed a female companion to raise children and women needed a male companion to work on the farm. Neither one could perform both childcare and the chores necessary to earn a living in an agricultural society, and your deceased spouse’s family members were already people you knew. They already loved your children too.

Neither of these situations is historically unusual, but both are very difficult to determine using genetics alone, even in the current generation.

Neither X-DNA nor mitochondrial DNA will be helpful, and Y-DNA will generally not be either.

Unfortunately, three-quarter siblings’ autosomal DNA will fall in the range of both half and full siblings, although not at the bottom of the half-sibling range, nor at the top of the full sibling range – but that leaves a lot of middle ground.

I’ve found it almost impossible to prove this scenario without prior knowledge, and equally as impossible to determine which of multiple brothers is the father unless there is a very strong half-sibling match in addition.

The DNA-Sci blog discusses this phenomenon, but I can’t utilize comparison screenshots according to their terms of service.

Clearly, what we need are more known three-quarter siblings to submit data to be studied in order to (possibly) facilitate easier determination, probably based on the percentage frequency distribution of FIR/HIR segments. Regardless, it’s never going to be 100% without secondary genealogical information.

Three-quarter siblings aren’t very common today, but they do exist. If you suspect something of this nature, really need the answer, and have exhausted all other possibilities, I recommend engaging a very experienced genetic genealogist with experience in this type of situation. However, given the random nature of recombination in humans, we may never be able to confirm using any methodology, with one possible exception.

There’s one possibility using Y-DNA if the parents in question are two brothers. If one brother has a Y-DNA SNP mutation that the other does not have, and this can be verified by testing either the brothers who are father candidates or their other known sons via the Big Y-700 test – the father of the siblings could then be identified by this SNP mutation as well. Yes, it’s a long shot.

Three-quarter sibling situations are very challenging.

Step-siblings, on the other hand, are easy.

Step-Siblings

Step-siblings don’t share either parent, so their DNA will not match to each other unless their parents are somehow related to each other. Please note that this means either of their parents, not just the parents who marry each other.

One child’s parent marries the other child’s parent, resulting in a blended family. The children then become step-siblings to each other.

The terms step-sibling and half-sibling are often used interchangeably, and they are definitely NOT the same.

Adopted Siblings

Adopted siblings may not know they are adopted and believe, until DNA testing, that they are biological siblings.

Sometimes adopted siblings are either half-siblings or are otherwise related to each other but may not be related to either of their adoptive parents. Conversely, adopted siblings, one or both, may be related to one of their adoptive parents.

The same full and half-sibling relationship genetic clues apply to adopted siblings, as well as the tools and techniques in the In Search of Unknown Family series of articles.

Donor-Conceived Siblings

Donor-conceived siblings could be:

  • Half-siblings if the donor is the same father but a different mother.
  • Half-siblings if they share an egg donor but not a father.
  • Full siblings if they are full biological siblings to each other, meaning both donors are the same but not related to the woman into whom the fertilized egg was implanted, nor to her partner, their legal parents.
  • Not biologically related to each other or either legal parent.
  • Biologically related to one or both legal parents when a family member is either an egg or sperm donor.

Did I cover all of the possible scenarios? The essence is that we literally know nothing and should assume nothing.

I have known of situations where the brother (or brothers) of the father was the sperm donor, so the resulting child or children appear to be full or three-quarters siblings to each other. They are related to their legal father who is the mother’s partner. In other words, in this situation, the mother’s husband was infertile, and his brother(s) donated sperm resulting in multiple births. The children from this family who were conceived through different brothers and had very close (half-sibling) matches to their “uncles'” children were very confused until they spoke with their parents about their DNA results.

The same techniques to ascertain relationships would be used with donor-conceived situations. Additionally, if it appears that a biological relationship exists, but it’s not a full or half-sibling relationship, I recommend utilizing other techniques described in the In Search of Unknown Family series.

Twins or Multiple Birth Siblings

Two types of twin or multiple birth scenarios exist outside of assisted fertilization.

Fraternal twins – With fraternal or dizygotic twins, two eggs are fertilized independently by separate sperm. Just view this as one pregnancy with two siblings occupying the same space for the same 9 months of gestation. Fraternal twins can be male, female or one of each sex.

Fraternal twins are simply siblings that happen to gestate together and will match in the same way that full siblings match.

Please note that it’s possible for two of a woman’s eggs to be fertilized at different times during the same ovulation cycle, potentially by different men, resulting in twins who are actually half-siblings.

A difference in ethnicity is NOT a reliable indicator of fraternal or identical twins. Submitting your own DNA twice often results in slightly different ethnicity results.

Identical twins – Identical or monozygotic twins occur when one egg is fertilized by one sperm and then divides into multiple embryos that develop into different children. Those children are genetically identical since they were both developed from the same egg and sperm.

Two of the most famous identical twins are astronauts Mark and Scott Kelly.

Identical twins are the same sex and will look the same because they have the same DNA, except for epigenetic changes, but of course external factors such as haircuts, clothes and weight can make identical twins physically distinguishable from each other.

DNA testing companies will either identify identical twins as “self,” “identical twin” or “parent/child” due to the highest possible shared cM count plus fully matching FIR regions.

For identical twins, checking the FIR versus HIR is a positive identification as indicated above at GEDmatch with completely solid green FIR regions. Do not assume twins that look alike are identical twins.

Siblings

Whoever thought there would be so many kinds of siblings!

If you observe the need to educate about either sibling terminology or DNA identification methodologies, feel free to share this article. When identifying relationships, never assume anything, and verify everything through multiple avenues.

_____________________________________________________________

Follow DNAexplain on Facebook, here or follow me on Twitter, here.

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.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research

So, You Want to Become a Professional Genetic Genealogist

I get asked quite often about what is required to become a professional genetic genealogist.

That’s actually two separate questions.

  • What is required to become a professional genealogist?
  • Then, what is required to specialize as a genetic genealogist?

What It’s Not

Before we have this discussion, I need to make sure that you understand that I’m NOT talking about forensics, meaning IGG, or investigative genetic genealogy in this article.

  • This is NOT forensics (IGG)
  • This is also not a specialty in finding missing parents for adoptees and others searching for unknown parents.

Both IGG and adoption searches utilize the same methodology, a subset of genetic genealogy. I wrote about that in Identifying Unknown Parents and Individuals Using DNA Matching.

The difference between genetic genealogy more broadly and IGG is:

  • What you’re searching for
  • The perspective
  • The methods utilized.

Essentially, the functional difference is that genealogists know who they are and have some information about their ancestors. For example, they know who their parents are and probably at least their grandparents. Genealogists are using both DNA testing and traditional genealogical paper trail research methods to focus and make discoveries going backwards in time.

Both IGG and unknown parent research uses DNA and (sometimes some) paper trail genealogy to find ways to connect the closest matches to the DNA tester (or DNA sample) together to each other to identify either living or recently living people. For example, two people who are are first cousins to the tester should both have the same grandparents if they are related to the tester through the same parent.

If two people who are related to the tester as first cousins do not share the same grandparent(s), then they are related to the tester through different parents of the tester.

The commonality is that DNA testing and some types of records are used for:

  • IGG where you’re searching for the identity of the tester or DNA sample
  • Unknown parent(s) searches where you are searching for the identity of the parent(s)
  • Genetic genealogy

However, the search methodology is different for IGG and unknown parents than for genealogy.

With IGG and unknown parent searches, you’re looking for your closest matches, then attempting to connect them together to identify either currently living or recently living people.

This article focuses specifically on genealogy and genetic genealogy, meaning looking backwards in time to identify ancestors.

I wrote about the techniques used for both IGG and parental searching in the article, Identifying Unknown Parents and Individuals Using DNA Matching.

What Do Genealogists Do?

Genealogy is the study of family history and the descent of a person or a family. Genealogists use a variety of sources and methods to discover and show the ancestry of their subjects and in doing so, create the family trees that are familiar to all of us.

Genealogists use different sources and methods to find and show the descent and kinship of their subjects.

Traditional sources include but are not limited to the following record types:

  • Vital records (birth, marriage, and death certificates)
  • Census
  • Military
  • Immigration
  • Land and tax records
  • Wills and probate
  • Church records
  • Newspapers
  • Obituaries
  • Published and online books
  • Oral histories
  • Genealogy databases
  • And more

Of course, today the four types of DNA can be added to that list.

A professional genealogist needs to know how and where to find these types of records in the target area, any unique cultural or regional factors affecting those records, and how to interpret them both individually and together.

For example, in a deed record in colonial Virginia, why would, or wouldn’t a female release her dower right? What is dower right, and why is it important? How might that record, or lack thereof, affect future probate for that woman/couple? In what type of historical or court record book might one look for these types of records?

Genealogists also need to know how to weigh different types of information in terms of potential accuracy and how to interpret primary and secondary sources.

Primary sources are those that were created at or near the time of an event by someone who was present at the event or who had first-hand knowledge of it. Examples of primary sources include birth certificates, marriage licenses, and census records, although census records are far more likely to be inaccurate or incomplete than a birth certificate or marriage record. Genealogists need to understand why, and where to look for corroboration. Primary sources are considered to be most accurate.

Secondary sources are those that were created later by someone who did not have first-hand knowledge of the event. Examples of secondary sources include family histories and genealogies, published biographies, and sometimes, newspaper articles.

The genealogists “go to” source for understanding and interpreting evidence is Evidence Explained by Elizabeth Shown Mills, available here.

Of course, DNA understanding and analysis needs to be added to this list and has become an important resource in genealogy. Additionally, genetic genealogy has become a specialty within the broader field of genealogy, as has IGG.

Put another way, a genealogist should have expertise and a specialty in some area. Maybe Italian records, or Native American genealogy, or New England records, in addition to the basic skills. At one time, a genealogist didn’t necessarily HAVE TO have expertise in genetic genealogy as well, but that has changed in the past few years. A professional genealogist should MINIMALLY understand the basics of genetic genealogy and when/how it can be useful. They may or may not have ready access to a genetic genealogist within the company where they work.

Being an independent genealogist, unless you specialize only in a specific area, like Dutch genealogy, is much more challenging because you’ll need to be proficient in BOTH Dutch genealogy AND genetic genealogy. It’s tough keeping up with one specialty, let alone two, although in this case, Yvette does an amazing job. However, her primary specialty is Dutch genealogy, and genetic genealogy is the booster rocket when appropriate. Genetic genealogy is not always needed for traditional genealogy, which is why genetic genealogy is a specialty skill.

In addition to all that, you also need to be proficient and comfortable with technology and a good communicator. Walking on water is also helpful:)

Job Description

So, what does the job description for a genealogist look like?

I reached out to Legacy Tree Genealogists because they are one of the largest, if not the largest genealogy research company, and they partner with 23andMe, FamilyTreeDNA, and MyHeritage. Legacy Tree has specialists in many regions and languages, in addition to six genetic genealogists on staff.

Fortunately, they have a job listing posted right now, here, with an excellent description of what is expected.

If you’re interested or wish to sign up for notifications, click here.

Understanding that this job description won’t be posted forever, I reached out to the owner, Jessica Dalley Taylor, and asked if she would send me a sample description to include in this article.

Here you go, courtesy of Jessica:

About You

It’s not easy to make each client’s experience the very best it can possibly be, and it means we can only hire an exceptional genealogist for this position. You will be a great fit if:

    • You are fluent in English and can explain your genealogy discoveries in a way that clients connect with and understand
    • You have taken at least one genetic genealogy test or administered the test of a relative
    • You have introductory genetic genealogy abilities
    • You have at least intermediate traditional genealogical research experience in any geographic locality
    • You are familiar with the repositories of the areas for which you claim expertise and have worked with them to obtain documents
    • You are passionate about genealogy and are a creative problem solver
    • You are great at working independently and hitting deadlines (please don’t overlook this line about deadlines)
    • You are comfortable with Microsoft Office suite
    • You’re familiar with genealogical technology such as pedigree software
    • You have a quiet place to work without distractions, a computer, and great internet
    • You have a strong desire to work as a professional genetic genealogist

Even better if:

    • You have a basic understanding of genetic inheritance and its application to genealogy
    • You have beginning experience with interpretation and use of genetic genealogy test results
    • You have intermediate-level genetic genealogy abilities

What you’ll be doing at Legacy Tree:

    • You’ll be learning how to use genetic testing in identifying family
    • You’ll be learning how to create high-quality research reports
    • You’ll be reading and formatting reports by professional researchers
    • You’ll be assisting with researching and writing genealogy reports
    • You’ll be performing genetic genealogy analysis under the direction of professional mentors
    • You’ll be developing advanced-level genetic genealogy skills and abilities
    • With your input, you’ll do other things as opportunities and needs arise

Please note that Legacy Tree offers both traditional genealogy services, combined with genetic genealogy, along with adoption and unknown parent searches.

As a measure of fundamental basic genetic genealogy skills, you should be able to create and teach a class like First Steps When Your DNA Results Are Ready – Sticking Your Toe in the Genealogy Water.

You should also be able to read and fully comprehend the articles on this blog, as well as explain the content to others. A very wise person once told me that if you can’t explain or teach a topic, you don’t understand it.

As luck would have it, Ancestry also posted a job opening for a genealogist as I was finishing this article. Here’s part of the job requirements.

Contractor or Employee

Please note that many companies have shifted their primary hiring strategy to utilizing contractors for not more than half time, especially now that working remotely has become the norm.

This may or may not be good news for you.

It allows the company to avoid paying benefits like insurance, vacation, leave, and retirement programs which reduces their costs. You may not need these benefits, and it may represent an opportunity for you. For others who need those benefits, it’s a deal-breaker.

Contracting may provide the ability to work part-time, but contracting probably means you need to have business management skills not required when you work for someone else. Let’s just say that I make quarterly estimated tax payments and my annual CPA bill is in the $2,000 range.

Compensation

Pay, either as an employee or contractor for a company, is a sticky wicket in this field.

First, there’s a consumer mindset, although not universal, that genealogy “should be” free. In part, this is due to search angels and a history of well-intentioned people making things free. I’m one of them – guilty as charged – this blog is free. My hourly work, however, when I accepted clients (which I DO NOT now,) was not free.

However, that “should be free” mindset makes it difficult to shift to a “pay to play” mentality when people can go on social media and get what they want for free.

Professional services are not and should not be free.

Professionals should be able to earn a respectable living. The full-time Ancestry job, posted above, with those credentials, nets out to $21.63 per hour for a 40-hour week, with a graduate degree preferred. For comparison, google other jobs and professions.

If you doubt for one second whether professional services should or should not be free, especially ones that require a bachelor’s degree or master’s, just think about what your CPA would do if you asked them to do your taxes because they have the ability, for free. Same for a doctor, lawyer, or any other professional.

People are often shocked at the rates paid to employees versus the rates charged to prospective customers. This discussion has recently gotten spicy on social media, so I’m not going to comment other than to say that when I did take private clients, which I DO NOT ANYMORE, I found it much more beneficial to operate independently than to work for a company.

However, I also had a readily recognizable specialty and an avenue to reach potential clients.

I also already had a business structure set up, and a CPA, and perhaps more important than either of those – I had medical insurance already in place.

The need for benefits is what drives many people to work for companies, which I fully understand. It’s also a big factor in why there are more female genealogists than male genealogists. Married women in the US are eligible to be covered by their spouse’s insurance, assuming the spouse has insurance through their employer.

My very strong recommendation to you is to weigh all of the factors and NEVER to find yourself without medical insurance or coverage.

If you’re going to be “self-employed,” set up a company. If you’re going to set up a company, do it properly, understand the tax ramifications of the various types of corporations and engage a competent CPA to shepherd you through the process from day 1 through taxes. They are worth every penny.

Look at various jobs in the market, review at the associated pay, get a quote for genealogy services of the type you would be providing from the various companies – and decide if this profession is really for you.

I don’t mean to be a wet blanket, just a realist.

Training and Certification

Now for the good news and the bad news.

  • There is professional training for genealogy
  • There are certifications for genealogy
  • There is no “one place” for either
  • There is no certification for genetic genealogy
  • There’s a LOT of misunderstanding and misinformation about genetic genealogy
  • Genetic genealogy changes often

You need to view your education for genealogy/genetic genealogy in the same way you’d view obtaining a college degree – plus continuing education to maintain your education and skills at a current and functional level.

And yes, all of that costs money. If you decide to work for a company, be sure to ask if continuing ed is on their dime and time, or yours.

Genealogy Training

The Board for Certification of Genealogists, BCG, allows graduates to append CG, for Certified Genealogist after their name. BCG is focused on certification of skills and is not a training platform, although they do provide some webinars, etc. It’s not a college curriculum though. Certification is the “end game” for many. Candidates must submit a portfolio for evaluation, complete in a specific timeframe, and must reapply every five years to maintain their certification.

Not all genealogists are certified by BCG, and BCG only lists references of BCG members.

In the field of Genetic Genealogy, that can be problematic because many competent and well-known people are not BCG certified. BCG does not have a genetic genealogy certification.

Lack of BCG certification does not mean that someone is not qualified, and BCG certification certainly does NOT mean or imply that the individual is competent in genetic genealogy, which has more and more become a part of almost every genealogical puzzle. If not for initial discovery, for confirmation.

There are many avenues for genealogical training, including, but not limited to:

  • Brigham Young University Family History Degree
  • NGS Home Study Course
  • Salt Lake Institute of Genealogy (SLIG)
  • Genealogical Research Institute of Pittsburgh (GRIP)
  • Boston University Certificate program
  • Genealogical Institute on Federal Records (Gen-Fed)
  • Institute of Genealogy and Historical Research (IGHR)
  • University of Strathclyde
  • University of Dundee
  • Major Conferences, including RootsTech and NGS, among others
  • Specialty conferences such as the International Conference on Jewish Genealogy (IAJGS)
  • Online conferences and conference proceedings such as Rootstech who maintains a free library of their virtual and recorded conference sessions.
  • Legacy Family Tree Webinars
  • Videos produced by major genealogy companies such as MyHeritage, FamilyTreeDNA and Ancestry, often available through their website, Youtube or both
  • Blogs and learning/help centers of the major genealogy companies

Genetic Genealogy Training

Genetic genealogy training is more challenging because there is no specific program, curriculum, or certification.

Many genetic genealogists obtained their experience as a part of genealogy over 15 or 20 years and have focused on the genetic aspect of genealogy. Several of us had a scientific background that meshed well with this field and is part of why we discovered that our passion is here.

Before I provide this resource list, I need to emphatically state that probably 95% of answers that I see provided on social media platforms in response to questions asked by people are either entirely incorrect, partially incorrect in a way that makes me want to say, “well, not exactly,” or are incomplete in a way that makes a significant difference.

I chose and choose to focus on creating educational tools and making explanations available for everyone, in one place, not one question at a time.

I began publishing my blog in 2012 as an educational tool and I’m dumbstruck by how many people just want a yes or no answer instead of learning. If one doesn’t take the time to learn, they have no idea if the answers they receive are valid, or if there’s more to the story that they are missing.

Social media can mislead you badly if you don’t have the ability to discern between accurate answers, partially accurate answers, and incorrect answers. Furthermore, opinions differ widely on some topics.

Unfortunately, because there is no genetic genealogy credentialling, there is also no “post-nominal letters,” such as CG for certified genealogist. Therefore, a novice has absolutely no idea how to discern between an expert and another overly helpful novice who is unintentionally providing incorrect or partial information.

Many of us who at one time reliably answered questions have simply gotten burned out at the same question being asked over and over, and no longer regularly engage. Burnout is real. Another issue is that askers often don’t provide enough, or accurate, information, so a significant amount of time is spent in clarifying the information around a question. Furthermore, your CPA, lawyer, and physician don’t answer questions online for free, and neither do most people who are busy earning a living in this field.

DNA educational opportunities, some of which are contained within larger conference agendas, include:

There are other blogs, of course, some of which were launched by well-known genetic genealogists but are no longer maintained. Blogging is quite time-consuming.

I’ve covered all kinds of genetic genealogy topics in my blog articles. They are a good source of information, education and hands-on training. I attempt to publish two articles weekly, and there are over 1600 available for your enjoyment.

In addition to the initial learning period, you’ll need to make time to stay engaged and maintain your genealogy and genetic genealogy skills.

Apprenticeship

In addition to training, I think you’d need at least a year interning or working at a junior learning level, minimum. Think of it as your genealogy residency.

  • You could choose to work for a vendor in their help center.
  • You could choose to work for a genealogy company. I’ve mentioned the largest ones, but there are others as well.
  • You could choose to work on your own case studies and those of your friends and family, but if you do, be aware that you won’t have anyone reviewing your work. If you make a mistake or should have approached something differently, and you’re working alone, there’s no one to tell you.
  • You could work as a search angel for others. I have mixed emotions about this, in part due to the lack of review and oversight. But also, in part because “free search angels” perpetuate the idea that genealogy “should be” free.

If you want to work in IGG, after training, an internship under an established mentor is ABSOLUTELY ESSENTIAL for a minimum of 100 or so successful closures.

Genealogists and genetic genealogists have the ethical responsibility to NOT MAKE MISTAKES when working on other people’s family. You need to know what you know, what you don’t know, when to get help, from where and with whom.

Networking Opportunity

A Facebook group named “Genealogy Jobs” has been established to discuss opportunities and all of the topics surrounding this subject.

There’s a Genealogy Career Day event on April 22nd where you can interact with professionals including authors, freelance genealogists, certified genealogists, business owners, and an investigative genetic genealogist. Take a look at the topics. If you’re considering whether or not you want to go pro, you’ll be interested. You can sign up here.

The sessions will be uploaded to their YouTube channel, here, after the event.

I hope you’ve found this article useful and helps you decide if this profession is for you. If so, create a plan and execute.

If you decide you do want to go pro, I wish you the best and welcome you to the fast-paced world of professional genealogy or its specialty, genetic genealogy.

____________________________________________________________

Follow DNAexplain on Facebook, here or follow me on Twitter, here.

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.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research

X Chromosome Master Class

The X chromosome can be especially useful to genetic genealogists because it has a unique inheritance path. Thanks to that characteristic, some of the work of identifying your common ancestor is done just by simply HAVING an X match.

Unfortunately, X-DNA and X matching is both underutilized and somewhat misunderstood – in part because not all vendors utilize the X chromosome for matching.

The X chromosome has the capability of reaching further back in time and breaking down brick walls that might fall no other way.

Hopefully, you will read this article, follow along with your own DNA results and make important discoveries.

Let’s get started!

Who Uses the X Chromosome?

The X chromosome is autosomal in nature, meaning it recombines under some circumstances, but you only inherit your X chromosome from certain ancestors.

It’s important to understand why, and how to utilize the X chromosome for matching. In this article, I’ve presented this information in a variety of ways, including case studies, because people learn differently.

Of the four major testing vendors, only two provide X-DNA match results.

  • FamilyTreeDNA – provides X chromosome results and advanced matching capabilities including filtered X matching
  • 23andMe – provides X chromosome results, but not filtered X matching without downloading your results in spreadsheet format
  • Ancestry and MyHeritage do not provide X-DNA results but do include the X in your raw DNA file so you can upload to vendors who do provide X matching
  • GEDmatch – not a DNA testing vendor but a third-party matching database that provides X matching in addition to other tools

It’s worth noting at this point that X-DNA and mitochondrial DNA is not the same thing. I wrote about that, here. The source of this confusion is that the X chromosome and mitochondrial DNA are both associated in some way with descent from females – but they are very different and so is their inheritance path.

So, what is X-DNA and how does it work?

What is X-DNA?

Everyone inherits two copies of each of chromosomes 1-22, one copy of each chromosome from each of your parents.

That’s why DNA matching works and each match can be identified as “maternal” or “paternal,” depending on how your match is related to you. Each valid match (excluding identical by chance matches) will be related either maternally, or paternally, or sometimes, both.

Your 23rd chromosome is your sex determination chromosome and is inherited differently. Chromosome 23 is comprised of X and Y DNA.

Everyone inherits one copy of chromosome 23 from each parent.

  • Males inherit a Y chromosome from their father, which is what makes males male. They do not inherit an X chromosome from their father.
  • Males always inherit an X chromosome from their mother.
  • Females inherit an X chromosome from both parents, which is what makes them female. Females have two X chromosomes, and no Y chromosome.
Chromosome 23 Father Contributes Mother Contributes
Male Child Y chromosome X chromosome
Female Child X chromosome X chromosome

X-DNA and mitochondrial DNA are often confused, but they are not the same thing. In fact, they are completely different.

Mitochondrial DNA, in BOTH males and females is always inherited from only the mother and only descends from the direct matrilineal line, so only the mother’s mother’s mother’s direct line. X DNA can be inherited from a number of ancestors based on a specific inheritance path.

Everyone has both X-DNA AND mitochondrial DNA.

Because males don’t inherit an X chromosome from their father, X chromosome matching has a unique and specific pattern of descent which allows testers who match to immediately eliminate some potential common ancestors.

  • Males only inherit an X chromosome from their mother, which means they can only have legitimate X matches on their mother’s side of their tree.
  • Females, on the other hand, inherit an X chromosome from both their mother and father. Their father only has one X chromosome to contribute, so his daughter receives her paternal grandmother’s X chromosome intact.
  • Both males and females inherit their mother’s X chromosome just like any of the other 22 autosomes. I wrote about chromosomes, here.

However, the unique X chromosome inheritance path provides us with a fourth very useful type of DNA for genealogy, in addition to Y-DNA, mitochondrial and autosomal DNA.

For the vendors who provide X-matching, it’s included with your autosomal test and does not need to be purchased separately.

The Unique X Chromosome

The X chromosome, even though it is autosomal in nature, meaning it does recombine and divide in certain circumstances, is really its own distinct tool that is not equivalent to autosomal matching in the way we’re accustomed. We just need to learn about the message it’s delivering and how to interpret X matches.

FamilyTreeDNA is one of two vendors who utilizes X chromosome matching, along with 23andMe, which is another good reason to encourage your matches at other vendors to upload their DNA file to FamilyTreeDNA for free matching.

The four major vendors do include X-DNA results in their raw DNA download file, even if they don’t provide X-matching themselves. This means you can upload the results to either FamilyTreeDNA or GEDmatch where you can obtain X matches. I provided step-by-step download/upload instructions for each vendor here.

Let’s look how X matching is both different, and beneficial.

My X Chromosome Family Tree

We are going to build a simple case study. A case study truly is worth 1000 descriptions.

This fan chart of my family tree colorizes the X chromosome inheritance path. In this chart, males are colored blue and females pink, but the salient point is that I can inherit some portion of (or all of) a copy of my X chromosome from the colorized ancestors, and only those ancestors.

Because males don’t inherit an X chromosome from their father, they CANNOT inherit any portion of an X chromosome from their father’s ancestors.

Looking at my father’s half of the chart, at left, you see that I inherited an X chromosome from both of my parents, but my father only inherited an X chromosome from his mother, Ollie Bolton. His father’s portion of the tree is uncolored, so no X chromosome could have descended from his paternal ancestors to him. Therefore he could not pass any X chromosome segments to me from his paternal side – because he doesn’t have X DNA from his father.

Hence, I didn’t inherit an X chromosome from any of the people whose positions in the chart are uncolored, meaning I can only inherit an X chromosome from the pink or blue people.

Essentially any generational male to male, meaning father/son relationship is an X-DNA blocker.

I know positively that I inherited my paternal grandmother, Ollie Bolton’s entire X chromosome, because hers is the only X chromosome my father, in the fan chart above, had to give me. His entire paternal side of the fan chart is uncolored.

Men only ever inherit their X chromosome from their mother. The only exception to this is if a male has the rare genetic condition of Klinefelter Syndrome, also known as XXY. If you are an adult male, it’s likely that you’ll already know if you have Klinefelters, so that’s probably the last possibility you should consider if you appear to have paternal X matches, not the first.

Sometimes, men appear to have X matches on their father’s side, but (barring Klinefelter’s) this is impossible. Those matches must either be identical by chance, or somehow related in an unknown way on their mother’s side.

Everyone inherits an X chromosome from their mother that is some combination of the X from her father and mother. It’s possible to inherit all of your maternal grandmother or maternal grandfather’s X chromosome, meaning they did not recombine during meiosis.

Using DNA Painter as an X Tool

I use DNAPainter to track my matches and correlate segments with ancestors.

I paint my DNA segments for all my chromosomes at DNAPainter which provides me with a central tracking mechanism that is visual in nature and allows me to combine matches from multiple vendors who provide segment information. I provide step-by-step instructions for using DNAPainter, here.

This is my maternal X chromosome with my matches painted. I’ve omitted my matches’ names for privacy.

On the left side of the shaded grey column, those matches are from my maternal grandmother’s ancestors. On the right side, those matches are from my maternal grandfather’s ancestors.

The person in the grey column descends from unknown ancestors. In other words, I can tell that they descend from my maternal line, but I can’t (yet) determine through which of my two maternal grandparents.

There’s also an area to the right of the grey column where there are no matches painted, so I don’t know yet whether I inherited this portion of my X chromosome from my maternal grandmother or maternal grandfather.

The small darker pink columnar band is simply marking the centromere of the chromosome and does not concern us for this discussion.

Click on any image to enlarge

In this summary view of my paternal X chromosome, above, it appears that I may well have inherited my entire X chromosome from my paternal great-grandmother. We know, based on our inheritance rules that I clearly received my paternal grandmother’s X chromosome, because that’s all my father had to give me.

However, by painting my matches based on their ancestors, and selecting the summary view, you can see that most of my paternal X chromosome can be accounted for, with the exception of rather small regions with the red arrows.

It’s not terribly unusual for either a male or female to inherit their entire maternal X chromosome from one grandparent, or in this case, great-grandparent.

Of course, a male doesn’t inherit an X chromosome from their father, but a female can inherit her paternal X chromosome from either or both paternal grandparents.

Does Size Matter?

Generally speaking, an X match needs to be larger than a match on the other chromosomes to be considered genealogically equivalent in the same timeframe as other autosomal matches. This is due to:

  • The unique inheritance pattern, meaning fewer recombination events occurred.
  • The fact that X-DNA is NOT inherited from several lines.
  • The X chromosome has lower SNP density, meaning it contains fewer SNPs, so there are fewer possible locations to match when compared to the other chromosomes.

I know this equivalency requirement sounds negative, but it’s actually not. It means 7 cM (centimorgans) of DNA on the X chromosome will reach back further in time, so you may carry the DNA of an ancestor on the X chromosome that you no longer carry on other chromosomes. It may also mean that older segments remain larger. It’s actually a golden opportunity.

It sounds much more positive to say that a 16 cM X match for a female, or a 13 cM X match for a male is about the same as a 7 cM match for any other autosomal match in the same generation.

Of course, if the 7 cM match gets divided in the following generation, it has slipped below the matching threshold. If a 16 or 13 cM X match gets divided, it’s still a match. Plus, in some generations, if passed from father to daughter, it’s not divided or recombined. So a 7 cM X match may well be descended from ancestors further back in time.

X Chromosome Differences are Important!

Working with our great-great grandparent’s generation, we have 16 direct ancestors as illustrated in the earlier fan chart.

Given that females inherit from 8 X-chromosome ancestors in total, they are going to inherit an average of 45.25 cM of X-DNA from each of those ancestors. Females have two X chromosomes for a total length of 362 cM of X-DNA from both parents.

A male only has one X chromosome, 181 cM in length, so he will receive an average of 36.2 cM from each of 5 ancestors, and it’s all from his mother’s side.

In this chart, I’ve shown the total number of cMs for all of the autosomes, meaning chromosomes 1-22 and, separately, the X for males and females.

  • The average total cM for chromosomes 1-22 individually is 304 cM. (Yes, each chromosome is a different length, but that doesn’t matter for averages.)
  • That 304 cM can be inherited from any of 16 ancestors (in your great-grandparent’s generation)
  • The total number of cM on the X chromosomes for both parents for females totals 362
  • The total cM of X-DNA for males is 181 cM
  • The calculated average cM inherited for the X chromosome in the same generation is significantly different, shown in the bottom row.

The actual average for males and females for any ancestor on any random non-X chromosome (in the gg-grandparent generation) is still 19 cM. Due to the inheritance pattern of the X chromosome, the female X-chromosome average inheritance is 45.25 cM and the male average is 36.2 cM, significantly higher than the average of 19 cM that genetic genealogists have come to expect at this relationship distance on the other chromosomes, combined.

How Do I Interpret an X Match?

It’s important to remember when looking at X matching that you’re only looking at the amount of DNA from one chromosome. When you’re looking at any other matching amount, you’re looking at a total match across all chromosomes, as reported by that vendor. Vendors report total matching DNA differently.

  • The total amount of matching autosomal DNA does not include the X chromosome cMs at FamilyTreeDNA. X-DNA matching cMs are reported separately.
  • The total amount of matching autosomal DNA does include the X chromosome cMs in the total cM match at 23andMe
  • X-DNA is not used for matching or included in the match amount at either MyHeritage or Ancestry, but is included in the raw DNA data download files for all four vendors.
  • The total match amount shows the total for 22 (or 23) chromosomes, NOT just the X chromosome(s). That’s not apples to apples.

Therefore, an X match of 45 cM for a female or 36 for a male is NOT (necessarily) equivalent to a 19 cM non-X match. That 19 cM is the total for 22 chromosomes, while the X match amount is just for one chromosome.

You might consider a 20 cM match on the regular autosomes significant, but a 20 cM X-only match *could* be only roughly equivalent to a 10ish cM match on chromosomes 1-22 in the same generation. That’s the dog-leg inheritance pattern at work.

This is why FamilyTreeDNA does not report an X-only match if there is no other autosomal match. A 19 cM X match is not equivalent to a 19cM match on chromosomes 1-22. Not to mention, calculating relationships based on cM ranges becomes more difficult when the X is included.

However, the flip side is that because of the inheritance pattern of the X chromosome, that 19 cM match, if valid and not IBC, may well reach significantly further back in time than a regular autosomal matches. This can be particularly important for people seeking either Native or enslaved African ancestors for whom traditional records are elusive if they exist at all.

Critical Take-Away Messages

Here are the critical take-away messages:

  1. Because there are fewer ancestral lineages contributing to the tester’s X chromosome, the amount of X chromosomal DNA that a tester inherits from the ancestors who contribute to their X chromosome is increased substantially.
  2. The DNA of the contributing ancestors is more likely to be inherited, because there are fewer other possible contributing ancestors, meaning fewer recombination events or DNA divisions/recombinations.
  3. X-DNA is also more likely to be inherited because when passed from mother to son, it’s passed intact and not admixed with the DNA of the father.
  4. X matches cannot be compared equally to either percentages or cM amounts on any of the other chromosomes, or autosomal DNA in total, because X matching only reports the amount on one single chromosome, while your total cM match amount reports the amount of DNA that matches from all chromosomes (which includes the X at 23andMe).
  5. If you have X matches at 23andMe and/or FamilyTreeDNA, you can expect your total matching to be higher at 23andMe because they include the X matching cM in the total amount of shared DNA. FamilyTreeDNA provides the amount of X matching DNA separately, but not included in the total. MyHeritage and Ancestry do not include X matching DNA.

For clarity, at FamilyTreeDNA, you can see my shared DNA match with my mother. Of course, I match her on the total length of all my chromosomes, which is 3563 cM, the total Shared DNA for chromosomes 1-22. This includes all chromosomes except for the X chromosome which is reported separately at 181 cM. The longest contiguous block of shared DNA is 284 cM, the entire length of chromosome 1, the longest chromosome.

Because I’m a female, I match both parents on the full length of all 23 chromosomes, including 181 cM on both X chromosomes, respectively. Males will only match their mother on their X chromosome, meaning their total autosomal DNA match to their father, because the X is excluded, is 181 cM less than to their mother.

This difference in the amount of shared DNA with each parent, plus the differences in how DNA totals are reported by various vendors is also challenging for tools like DNAPainter’s Shared cM Tool which is based on the crowd sourced Shared cM Project that averages shared DNA numbers for known relationships at various vendors and translates those numbers into possible relationships for unknown matches.

Not all vendors report their total amount of shared DNA the same way. This is true for both X-DNA and half identical (HIR) versus fully identical (FIR) segments at 23andMe. This isn’t to say either approach is right or wrong, just to alert you to the differences.

Said Another Way

Let’s look at this another way.

If the average on any individual chromosome is 19 cMs for a relationship that’s 5 generations back in time. The average X-DNA for the same distance relationship is substantially more, which means that:

  • The X-DNA probably reaches further back in time than an equivalent relationship on any other autosome.
  • The X-DNA will have (probably) divided fewer times, and more DNA will descend from individual ancestors.
  • The inheritance path, meaning potential ancestors who contributed the X chromosomal DNA, is reduced significantly.

It’s challenging to draw equivalences when comparing X-DNA matching to the other chromosomes due to several variables that make interpretation difficult.

Based on the X-match size in comparison to the expected 19 cM single chromosome match at this genealogical distance, what is the comparable X-DNA segment size to the minimum 7 cM size generally accepted as valid on other chromosomes? What would be equal to a 7 cM segment on any other single random autosomal match, even though we know the inheritance probabilities are different and this isn’t apples to apples? Let’s pretend that it is.

This calculation presumes at the great-great-grandparent level that the 19 cM is in one single segment on a single chromosome. Now let’s divide 19 cM by 7 cM, which is 2.7, then divide the X amounts by the same number for the 7 cM equivalent of 16.75 cM for a female and 13.4 cM for a male.

When people say that you need a “larger X match to be equivalent to a regular autosomal match,” this is the phenomenon being referenced. Clearly a 7 cM X match is less relevant, meaning not equivalent, in the same generation as a 7 cM regular autosomal match.

Still, X matching compared to match amounts shown on the other chromosomes is never exact;u apples to apples because:

  • You’re comparing one X chromosome to the combined DNA amounts of many chromosomes.
  • The limited recombination path.
  • DNA from the other autosomes is less likely to be inherited from a specific ancestor.
  • The X chromosome has a lower SNP density than the other chromosomes, meaning fewer SNPs per cM.
  • The X-DNA may well reach further back in time because it has been divided less frequently.

Bottom Line

The X chromosome is different and holds clues that the other autosomes can’t provide.

Don’t dismiss X matches even if you can’t identify a common ancestor. Given the inheritance path, and the reduced number of divisions, your X-DNA may descend from an ancestor further back in time. I certainly would NOT dismiss X matches with smaller cMs than the 13 and 16 shown above, even though they are considered “equivalent” in the same generation.

X chromosome matching can’t really be equated to matching on the other chromosomes. They are two distinct tools, so they can’t be interpreted identically.

Different vendors treat the X chromosome differently, making comparison challenging.

  • 23andMe includes not only the X chromosome in their cM total, but doubles the Fully Identical Regions (FIR) when people, such as full siblings, share the same DNA from both parents. I wrote about that here.
  • Ancestry does not include the X in their cM match calculations.
  • Neither does MyHeritage.
  • FamilyTreeDNA shows an X match only when it’s accompanied by a match on another chromosome.

The Shared cM Project provides an average of all of the data input by crowdsourcing from all vendors, by relationship, which means that the cM values for some relationships are elevated when compared to the same relationship or even same match were it to be reported from a different vendor.

The Best Part!

The X chromosome inheritance pattern means that you’re much more likely to carry some amount of a contributing ancestor’s X-DNA than on any other chromosome.

  • X-DNA may well be “older” because it’s not nearly as likely to be divided, given that there are fewer opportunities for recombination.
  • When you’re tracking your X-DNA back in your tree, whenever you hit a male, you get an automatic “bump” back a generation to his mother. It’s like the free bingo X-DNA square!
  • You can immediately eliminate many ancestors as your most recent common ancestor (MRCA) with an X-DNA match.
  • Because X-DNA reaches further back in time, sometimes you match people who descend from common ancestors further back in time as well.

If you match someone on multiple segments, if one of those matching segments is X-DNA, that segment is more likely to descend from a different ancestor than the segments on chromosomes 1-22. I’ve found many instances where an X match descends from a different ancestor than matching DNA segments on the autosomes. Always evaluate X matches carefully.

Sometimes X-DNA is exactly what you need to solve a mystery.

Ok, now let’s step through how to use X-DNA in a real-life example.

Using X DNA to Solve a Mystery

Let’s say that I have a 30 cM X match with a male.

  • I know immediately that our most recent common ancestor (MRCA) is on HIS mother’s side.
  • I know, based on my fan chart, which ancestral lines are eliminated in my tree. I’ve immediately narrowed the ancestors from 16 to 5 on his side and 16 to 8 on my side.
  • Two matching males is even easier, because you know immediately that the common ancestor must be on both of their mother’s sides, with only 5 candidate lines each at the great-great-grandparent generation.

Female to female matches are slightly more complex, but there are still several immediately eliminated lines each. That means you’ve already eliminated roughly half of the possible relationships by matching another female on their X chromosome.

In this match with a female second cousin, I was able to identify who she was via our common ancestor based on the X chromosome path. In this chart, I’m showing the relevant halves of her chart at left (paternal), and mine (maternal), side by side.

I added blockers on her chart and mine too.

As it turns out, we both inherited most of our X chromosome from our great-grandparents, marked above with the black stars.

Several lines are blocked, and my grandfather’s X chromosome is not a possibility because the common ancestor is my maternal grandmother’s parents. My grandfather is not one of her ancestors.

Having identified this match as my closest relative (other than my mother) to descend on my mother’s maternal side, I was able to map that portion of my X chromosome to my great-grandparents Nora Kirsch and Curtis Benjamin Lore.

My X Chromosome at DNA Painter

Here’s my maternal X chromosome at DNAPainter and how I utilized chromosome painting to push the identification of the ancestors whose X chromosome I inherited back an additional two generations.

Using that initial X chromosome match with my second cousin, shown by the arrow at bottom of the graphic, I mapped a large segment of my maternal X chromosome to my maternal great-grandparents.

By viewing the trees of subsequent X maternal matches, I was then able to push those common segments, shown painted directly above that match with the same color, back another two generations, to Joseph Hill, born in 1790, and Nabby Hall. I was able to do that based on the fact that other matches descend from Joseph and Nabby through different children, meaning we all triangulate on that common segment. I wrote about triangulation at DNAPainter, here.

I received no known X-DNA from my great-grandmother, Nora Kirsch, although a small portion of my X chromosome is still unassigned in yellow as “Uncertain.”

I received a small portion of my maternal X chromosome, in magenta, at left, from my maternal great-great-grandparents, John David Miller and Margaret Lentz.

The X chromosome is a powerful tool and can reach far back in time.

In some cases, the X, and other chromosomes can be inherited intact from one grandparent. I could have inherited my mother’s entire copy of her mother’s, or her father’s X chromosome based on random recombination, or not. As it turns out, I didn’t, and I know that because I’ve mapped my chromosomes to identify my ancestors based on common ancestors with my matches.

X-DNA Advanced Matches at FamilyTreeDNA

At FamilyTreeDNA, the Advanced Matches tab includes the ability to search for X matches, either within the entire database, or within specific projects. I find the project selection to be particularly useful.

For example, within the Claxton project, my father’s maternal grandmother’s line, I recognize my match, Joy, which provides me an important clue as to the possible common ancestor(s) of our shared segments.

Joy’s tree shows that her 4-times great-grandparents are my 3-times great-grandparents, meaning we are 4th cousins once removed and share 17 cM of DNA on our X chromosome across two segments.

Don’t be deceived by the physical appearance of “size” on your chromosomes. The first segment that spans the centromere, or “waist” of the chromosome, above, is 10.29 cM, and the smaller segment at right is 7.02 cM. SNPs are not necessarily evenly distributed along chromosomes.

Remember, an X or other autosomal match doesn’t necessarily mean the entire match is contained in one segment so long as it’s large enough to be divided in two parts and survive the match threshold.

It’s worth noting that Joy and I actually share at least two different, unrelated ancestral lines, so I need to look at Joy’s blocked lines to see if one of those common ancestral lines is not a possibility for our X match. It’s important to evaluate all possible ancestors, plus the inheritance path to eliminate any lineage that involves a father to son inheritance on the X chromosome.

Last but not least, you may match on your X chromosome through a different ancestor than on other chromosomes. Every matching segment has its own individual history. It’s not safe to assume.

Now, take a look at your X chromosome matches at FamilyTreeDNA, 23andMe, and GedMatch. What will you discover?

_____________________________________________________________

Follow DNAexplain on Facebook, here or follow me on Twitter, here.

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.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research

The Best of 2022

It’s that time of year where we look both backward and forward.

Thank you for your continued readership! Another year under our belts!

I always find it interesting to review the articles you found most interesting this past year.

In total, I published 97 articles in 2022, of which 56 were directly instructional about genetic genealogy. I say “directly instructional,” because, as you know, the 52 Ancestors series of articles are instructional too, but told through the lives of my ancestors. That leaves 41 articles that were either 52 Ancestors articles, or general in nature.

It has been quite a year.

2022 Highlights

In a way, writing these articles serves as a journal for the genetic genealogy community. I never realized that until I began scanning titles a year at a time.

Highlights of 2022 include:

Which articles were your favorites that were published in 2022, and why?

Your Favorites

Often, the topics I select for articles are directly related to your comments, questions and suggestions, especially if I haven’t covered the topic previously, or it needs to be featured again. Things change in this industry, often. That’s a good thing!

However, some articles become forever favorites. Current articles don’t have enough time to amass the number of views accumulated over years for articles published earlier, so recently published articles are often NOT found in the all-time favorites list.

Based on views, what are my readers’ favorites and what do they find most useful?

In the chart below, the 2022 ranking is not just the ranking of articles published in 2022, but the ranking of all articles based on 2022 views alone. Not surprisingly, six of the 15 favorite 2022 articles were published in 2022.

The All-Time Ranking is the ranking for those 2022 favorites IF they fell within the top 15 in the forever ranking, over the entire decade+ that this blog has existed.

Drum roll please!!!

Article Title Publication Date 2022 Ranking All-Time Ranking
Concepts – Calculating Ethnicity Percentages January 2017 1 2
Proving Native American Ancestry Using DNA December 2012 2 1
Ancestral DNA Percentages – How Much of Them in in You? June 2017 3 5
AutoKinship at GEDmatch by Genetic Affairs February 2022 4
442 Ancient Viking Skeletons Hold DNA Surprises – Does Your Y or Mitochondrial DNA Match? Daily Updates Here September 2020 5
The Origins of Zana of Abkhazia July 2021 6
Full or Half Siblings April 2019 7 15
Ancestry Rearranged the Furniture January 2022 8
DNA from 459 Ancient British Isles Burials Reveals Relationships – Does Yours Match? February 2022 9
DNA Inherited from Grandparents and Great-Grandparents January 2020 10
Ancestry Only Shows Shared Matches of 20 cM and Greater – What That Means & Why It Matters May 2022 11
How Much Indian Do I Have in Me??? June 2015 12 8
Top Ten RootsTech 2022 DNA Sessions + All DNA Session Links March 2022 13
FamilyTreeDNA DISCOVER Launches – Including Y DNA Haplogroup Ages June 2022 14
Ancient Ireland’s Y and Mitochondrial DNA – Do You Match??? November 2020 15

2023 Suggestions

I have a few articles already in the works for 2023, including some surprises. I’ll unveil one very soon.

We will be starting out with:

  • Information about RootsTech where I’ll be giving at least 7 presentations, in person, and probably doing a book signing too. Yes, I know, 7 sessions – what was I thinking? I’ve just missed everyone so very much.
  • An article about how accurately Ancestry’s ThruLines predicts Potential Ancestors and a few ways to prove, or disprove, accuracy.
  • The continuation of the “In Search Of” series.

As always, I’m open for 2023 suggestions.

In the comments, let me know what topics you’d like to see.

_____________________________________________________________

Follow DNAexplain on Facebook, here or follow me on Twitter, here.

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.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research

Concepts: Your Matches on the Same Segment are NOT Necessarily Related to Each Other

Just because two (or more) people match you on the same segment does NOT mean they are related to each other.

This is a fundamental concept of DNA matching and of using a chromosome browser.

I want to make this concept crystal clear.

This past week, I’ve had two people contact me with the same question that’s based up on a critical misunderstanding, or maybe just lack of understanding.

It’s not intuitive – in fact, it’s counter-intuitive. I understand why they don’t understand.

It seems logical that if two or more people show up as a match to you on the chromosome browser, on the same segment, you’ve hit a home run and all you need to do is to identify their common ancestor who will also be your common ancestor, or at least related. Right?

NOT SO FAST!

Let’s walk through this, step-by-step. Once you “get it,” you’ll never forget it, and you can use this to help other people understand too. Please notice there are lots of links here to other articles I’ve written if you need refreshers or help with terms.

Yay! – I’ve Got Matches

OK, so you’ve just discovered that you have a close match with three people, on the same segment. You’re thrilled! Maybe you’re trying to identify your grandparent, so first or second cousin matches are VERY exciting for you.

They are also close enough matches with large enough segments that you don’t need to worry about false positive matches, meaning identical by chance.

Let’s take a look. I’m using FamilyTreeDNA because that’s where the majority of my family has tested, plus they have a nice chromosome browser and their unique matrix tool.

We have three nice-sized matches to people estimated to be my first or second cousins. I’ve selected all three and compared them in the chromosome browser. The large red match is 87 cM and the blue and teal matches are 39 cM each, and completely within the 87 cM segment, so completely overlapping.

I’ve hit the mother-lode, right?

All I need to do is identify THEIR common ancestor and I’ll surely find mine.

Right???

Nope

Just because they all three match ME on this same segment does NOT mean they all match each other and are from the same side of my family. All three people DO NOT NECESSARILY have the same ancestor. From this information alone, we cannot tell.

I know this seems counterintuitive, especially since you’re seeing them all on MY chromosomes – which are the background pallet.

However, remember that I have two chromosomes. One from my father and one from my mother.

These matches are ALWAYS FROM THE PERSPECTIVE OF THE TESTER.

So, I’m going to see matches in exactly the same location – matches on my mother’s chromosome and matches on my father’s chromosomes – painted on the same segment locations of my chromosome.

Let’s prove that in the simplest of ways.

Mom and Dad

This is my kit, compared with my Dad and Mom.

I only took a screen shot of my first several chromosomes, but you can see that I match both of my parents on the full length of each chromosome – on the same exact segments.

I am the background – the pallet upon which my matches are painted.

First, my father is painted, then my mother – their match to me displayed on my chromosomes.

I assure you, my father and mother are NOT related to each other. I’ll prove it.

I could simply select one parent, then look for the other parent on the shared matches list.

Or, I could use the Matrix tool, especially if I wanted to see if a group of people are related to me and also to each other.

The Matrix

The Matrix tool is available under “See More,” in the Autosomal DNA Results & Tools section.

The Matrix allows you to select 10 or fewer matches to see if they are matches to each other. We already know they are matches to you.

I added my parents into the matrix.

My parents do not match each other, meaning they are not genetically related, because their intersecting cell is not blue.

Next, let’s select those three other people I match and see if they match each other.

Yes indeed, we can see that Cheryl and Donald match each other, but Amos matches NEITHER Cheryl nor Don. Yet, the segments of Cheryl and Donald, who had the 39 cM blue and teal segments on the chromosome browser fall entirely within Amos’s 87 cM segment.

Therefore, if Cheryl and Donald do not match Amos, that means that Cheryl and Donald are from one side of my family, and Amos is from the other. This is absolutely true in this instance because we are comparing the exact same segment on my DNA, so everyone has to match me maternally or paternally, or by chance (IBC.) The segment size alone removes the possibility of IBC.

Each parent gave me one copy of chromosome 4, so everyone who matches me on chromosome 4 must match one or the other parent on that chromosome segment.

I’ve added my parents back into the comparison, at the bottom, with the three matches on chromosome 4. Now you can see that same segment again, and everyone matches me, parents included, of course.

There’s no way to tell the difference whether the blue, red and teal match is on my mother’s or father’s side without additional information.

Again, let’s prove it.

Everybody, Let’s Dance

I added my Mom and Dad back into the matrix.

You can see that Mom and Cheryl and Donald all match each other, plus me of course, by inference because these are my matches.

You can see that Amos and my Dad match each other, and me of course, but not the other people.

Settled

So, we’ve settled that, right.

In my case, I could provide this great example, because I do in fact have parental tests to use for comparison.

You can see when I remove my Dad and Amos that Cheryl and Donald and my Mom all match each other. If I were to remove my Mom, Cheryl and Donald would match each other.

If I remove Mom, Donald and Cheryl, Dad and Amos match each other.

Of course, you may not have either of your parents’ DNA to use as an anchor for matching. You may, in fact, be searching for a parent or close relative.

If you do have “anchor people,” by all means, use them. In fact, upload or create a tree, link your anchor people and as many others as possible to their profiles in your tree at FamilyTreeDNA so your matches will be automatically bucketed, meaning assigned maternally or paternally. FamilyTreeDNA is the only company that offers linking and triangulated bucketing.

But, if you’re searching for your parents or know nothing about your family, you won’t have an anchor point, so what’s next?

What’s Next?

Using a combination of matching, shared matches and the matrix, you can create your own grouping of matches.

My suggestion is to start with your 10 closest matches.

Pull all 10 into the matrix.

Remember, you will match these people across your chromosomes. The only question the matrix answers is “do my matches match each other,” and a “yes” doesn’t’ necessarily mean they match each other on the same line you match either or both of them on.

I’ve noted how each person is related to me.

You can see that there’s a large block of matches on my paternal side. Some are labeled “Father- both.” These people are related both maternally and paternally to my father, because either the families intermarried, or they are descendants of my paternal grandparents.

Three, Donald, Dennis and Cheryl are related on my mother’s side, but it’s worth noting that Dennis doesn’t match Cheryl or Donald. That doesn’t mean he’s not on my mother’s side, it simply means he descends through her maternal line, not the paternal line like Donald and Cheryl. Remember, we’re not comparing people who match on the same chromosome this time – we’re comparing my closest matches across all chromosomes, so it makes sense that my mother’s maternal matches won’t match her paternal matches, but they would both match Mom if she were in the matrix. Clearly they all match me or they would not be in my match list in the first place.

You could also run a Genetic Affairs AutoCluster or AutoTree to cluster your matches for you into groups, although you can’t select specifically which individuals to include, except by upper and lower thresholds.

Regardless of the method you select, you still need to do the homework to figure out the common ancestors, but it’s a lot easier knowing who also match each other.

Circling Back to the Beginning

Now, when you see those two or three or more people all matching you on the same segment on the chromosome browser, you KNOW that you can’t immediately assume they match you and therefore are all related to each other. It’s possible, and even probable that some of them will match you because they match your mother’s chromosome and some will match your father’s chromosome – so they are from different sides of your family.

The Matrix tool shows you, for groups of 10 or less, who also matches each other.

What you are doing by determining if multiple people share common segments and match each other is triangulation. I wrote about triangulation at each company in the articles below:

Unfortunately, Ancestry does not provide a chromosome browser, so triangulation is not possible, but Ancestry does provide shared matching with some caveats. However, some Ancestry customers do upload their DNA file to FamilyTreeDNA, MyHeritage or GEDmatch. You can find step-by-step download/upload instructions for all vendors, here.

Additional Resources

You’ve probably noticed there are lots of links in this article to other articles that I’ve written. You might want to go back and take a look at those if you’re in the process of educating yourself or need help wrapping your head around the “same segment address – two parents – your matches are not created equal” phenomenon.

Here are a couple of additional articles that will help you understand matching on both parents’ sides, and how to get the most out of matching, segments, triangulation and chromosome browsers.

I prepared a triangulation resource summary article, here:

Enjoy!!
____________________________________________________________

Follow DNAexplain on Facebook, here or follow me on Twitter, here.

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.

DNA Purchases and Free Uploads

Genealogy Products and Services

My Book

Genealogy Books

Genealogy Research