Autosomal DNA Matching Confidence Spectrum

Are you confused about DNA matches and what they mean…different kinds of matches…from different vendors and combined results between vendors.  Do you feel like lions and tigers and bears…oh my?  You’re not alone.

As the vendors add more tools, I’ve noticed recently that along with those tools has come a significant amount of confusion surrounding matches and what they mean.  Add to this issue confusion about the terminology being used within the industry to describe various kinds of matches.  Combined, we now have a verbiage or terminology issue and we have confusion regarding the actual matches and what they mean.  So, as people talk, what they mean, what they are trying to communicate and what they do say can be interpreted quite widely.  Is it any wonder so many people are confused?

I reached out within the community to others who I know are working with autosomal results on a daily basis and often engaged in pioneering research to see how they are categorizing these results and how they are referring to them.

I want to thank Jim Bartlett, Blaine Bettinger, Tim Janzen and David Pike (in surname alphabetical order) for their input and discussion about these topics.  I hope that this article goes a long way towards sorting through the various kinds of matches and what they can and do mean to genetic genealogists – and what they are being called.  To be clear, the article is mine and I have quoted them specifically when applicable.

But first, let’s talk about goals.

Goals

One thing that has become apparent over the past few months is that your goals may well affect how you interpret data.  For example, if you are an adoptee, you’re going to be looking first at your closest matches and your largest segments.  Distant matches and small segments are irrelevant at least until you work with the big pieces.  The theory of low hanging fruit, of course.

If your goal is to verify and generally validate your existing genealogy, you may be perfectly happy with Ancestry’s Circles.  Ancestry Circles aren’t proof, as many people think, but if you’re looking for low hanging fruit and “probably” versus “positively,” Ancestry Circles may be the answer for you.

If you didn’t stop reading after the last sentence, then I’m guessing that “probably” isn’t your style.

If your goal is to prove each ancestor and/or map their segments to your DNA, you’re not going to be at all happy with Ancestry’s lack of segment data – so your confidence and happiness level is going to be greatly different than someone who is just looking to find themselves in circles with other descendants of the same ancestor and go merrily on their way.

If you have already connected the dots on most of your ancestry for the past 4 or 5 generations, and you’re working primarily with colonial ancestors and those born before 1700, you may be profoundly interested in small segment data, while someone else decides to eliminate that same data on their spreadsheet to eliminate clutter.  One person’s clutter is another’s goldmine.

While, technically, the different types of tests and matches carry a different technical confidence level, your personal confidence ranking will be influenced by your own goals and by some secondary factors like how many other people match on a particular segment.

Let’s start by talking about the different kinds of matching.  I’ve been working with my Crumley line, so I’ll be utilizing examples from that project.

Individual Matching, Group Matching and Triangulation

There is a difference between individual matching, group matching and triangulation.  In fact, there is a whole spectrum of matching to be considered.

Individual Matching

Individual matching is when someone matches you.

confidence individual match

That’s great, but one match out of context generally isn’t worth much.  There’s that word, generally, because if there is one thing that is almost always true, it’s that there is an exception to every rule and that exception often has to do with context.  For example, if you’re looking for parents and siblings, then one match is all you need.

If this match happens to be to my first cousin, that alone confirms several things for me, assuming there is not a secondary relationship.  First, it confirms my relationship with my parent and my parent’s descent from their parents, since I couldn’t be matching my first cousin (at first cousin level) if all of the lines between me and the cousin weren’t intact.

confidence cousins

However, if the match is to someone I don’t know, and it’s not a close relative, like the 2nd to 4th cousins shown in the match above, then it’s meaningless without additional information.  Most of your matches will be more distant.  Let’s face it, you have a lot more distant cousins than close cousins.  Many ancestors, especially before about 1900, were indeed, prolific, at least by today’s standards.

So, at this point, your match list looks like this:

confidence match list

Bridget looks pretty lonely.  Let’s see what we can do about that.

Matching Additional People

The first question is “do you share a common ancestor with that individual?”  If yes, then that is a really big hint – but it’s not proof of anything – unless they are a close relative match like we discussed above.

Why isn’t a single match enough for proof?

You could be related to this person through more than one ancestral line – and that happens far more than I initially thought.  I did an analysis some time back and discovered that about 15% of the time, I can confirm a secondary genealogical line that is not related to the first line in my tree.  There were another 7% that were probable – meaning that I can’t identify a second common ancestor with certainty, but the surname and location is the same and a connection is likely.  Another 8% were from endogamous lines, like Acadians, so I’m sure there are multiple lines involved.  And of those matches (minus the Acadians), about 10% look to have 3 genealogical lines, not just two.  The message here – never assume.

When you find one match and identify one common genealogical line, you can’t assume that is how you are genetically related on the segment in question.

Ideally, at this point, you will find a third person who shares the common ancestor and their DNA matches, or triangulates, between you and your original match to prove the connection.  But, circumstances are not always ideal.

What is Triangualtion?

Triangulation on the continuum of confidence is the highest confidence level achievable, outside of close relative matching which is evident by itself without triangulation.

Triangulation is when you match two people who share a common ancestor and all three of you match each other on that same segment.  This means that segment descended to all three of you from that common ancestor.

This is what a match group would look like if Jerry matches both John and Bridget.

confidence example 1 match group

Example 1 – Match Group

The classic definition of triangulation is when three people, A, B and C all match each other on the same segment and share a known, identifiable common ancestor.  Above, we only have two.  We don’t know yet if John matches Bridget.

A matches B
A matches C
B matches C

This is what an exact triangulation group would look like between Jerry, John and Bridget.  Most triangulation matches aren’t exact, meaning the start and/or end segment might be different, but some are exact.

confidence example 2 triangulation group

Example 2 – Triangulation Group

It’s not always possible to prove all three.  Sometimes you can see that Jerry matches Bridget and Jerry matches John, but you have no access to John or Bridget’s kits to verify that they also match each other.  If you are at Family Tree DNA, you can run the ICW (in common with) tool to see if John and Bridget do match each other – but that tool does not confirm that they match on the same segment.

If the individuals involved have uploaded their kits to GedMatch, you have the ability to triangulate because you can see the kit numbers of your matches and you can then run them against each other to verify that they do indeed match each other as well.  Not everyone uploads their kits to GedMatch, so you may wind up with a hybrid combination of triangulated groups (like example 2, above) and matching groups (like example 1, above) on your own personal spreadsheet.

Matching groups (that are not triangulated) are referred to by different names within the community.  Tim Janzen refers to them as clusters of cousins, Blaine as pseudo triangulation and I have called them triangulation groups in the past if any three within the group are proven to be triangulated. Be careful when you’re discussing this, because matching groups are often misstated as triangulated groups.  You’ll want to clarify.

Creating a Match List

Sometimes triangulation options aren’t available to us.  For example, at Family Tree DNA, we can see who matches us, and we can see if they match each other utilizing the ICW tool, but we can’t see specifically where they match each other.  This is considered a match group.  This type of matching is also where a great deal of confusion is introduced because these people do match each other, but they are NOT (yet) triangulated.

What we know is that all of these people are on YOUR match list, but we don’t know that they are on each other’s match lists.  They could be matching you on different sides of your DNA or, if smaller segments, they might be IBC (identical by chance.)

You can run the ICW (in common with) tool at Family Tree DNA for every match you have.  The ICW tool is a good way to see who matches both people in question.  Hopefully, some of your matches will have uploaded trees and you can peruse for common ancestors.

The ICW tool is the little crossed arrows and it shows you who you and that person also match in common.

confidence match list ftdna

You can run the ICW tool in conjunction with the ancestral surname in question, showing only individuals who you have matches in common with who have the Crumley surname (for example) in their ancestral surname list.  This is a huge timesaver and narrows your scope of search immediately.  By clicking on the ICW tool for Ms. Bridget,  you see the list, below of those who match both the person whose account we are signed into and Ms. Bridget, below.

confidence icw ftdna

Another way to find common matches to any individual is to search by either the current surname or ancestral surnames.  The ancestral surname search checks the surnames entered by other participants and shows them in the results box.

In the example above, all of these individuals have Crumley listed in their surnames.  You can see that I’ve sorted by ancestral surname – as Crumley is in that search box.

Now, your match lists looks like this relative to the Crumley line.  Some people included trees and you can find your common ancestor on their tree, or through communications with them directly.  In other cases, no tree but the common surname appears in the surname match list.  You may want to note those results on your match list as well.

confidence match list 2

Of course, the next step is to compare these individuals in a matrix to see who matches who and the chromosome browser to see where they match you, which we’ll discuss momentarily.

Group Matching

The next type of matching is when you have a group of people who match each other, but not necessarily on the same segment of DNA.  These matching groups are very important, especially when you know there is a shared ancestor involved – but they don’t indicate that the people share the same segment, nor that all (or any) of their shared segments are from this particular ancestor.  Triangulation is the only thing that accomplishes proof positive.

This ICW matrix shows some of the Crumley participants who have tested and who matches whom.

confidence icw grid

You can display this grid by matching total cM or by known relationship (assuming the individuals have entered this information) or by predicted relationship range.  The total cMs shared is more important for me in evaluating how closely this person might be related to the other individual.

The Chromosome Browser

The chromosome browser at Family Tree DNA shows matches from the perspective of any one individual.  This means that the background display of the 22 Chromosomes (plus X) is the person all of the matches are comparing against. If you’re signed in to your account, then you are the black background chromosomes, and everyone is being compared against your DNA.  I’m only showing the first 6 chromosomes below.

confidence chromosome browser

You can see where up to 5 individuals match the person you’re comparing them to.  In this case, it looks like they may share a common segment on chromosome 2 among several descendants.  Of course, you’d need to check each of these individuals to insure that they match each other on this same segment to confirm that indeed, it did come from a common ancestor.  That’s triangulation.

When you see a grouping of matches of individuals known to descend from a common ancestor on the same chromosome, it’s very likely that you have a match group (cluster of cousins, pseudo triangulation group) and they will all match each other on that same segment if you have the opportunity to triangulate them, but it’s not absolute.

For example, below we have a reconstructed chromosome 8 of James Crumley, the common ancestor of a large group of people shown based on matches.  In other words, each colored segment represents a match between two people.  I have a lot more confidence in the matches shown with the arrows than the single or less frequent matches.

confidence chromosome 8 match group'

This pseudo triangulation is really very important, because it’s not just a match, and it’s not triangulation.  The more people you have that match you on this segment and that have the same ancestor, the more likely that this segment will triangulate.  This is also where much of the confusion is coming from, because matching groups of multiple descendants on the same segments almost always do triangulate so they have been being called triangulation groups, even when they have not all been triangulated to each other.  Very occasionally, you will find a group of several people with a common ancestor who triangulate to each other on this common segment, except one of a group doesn’t triangulate to one other, but otherwise, they all triangulate to others.

confidence triangulation issue

This situation has to be an error of some sort, because if all of these people match each other, including B, then B really must match D.  Our group discussed this, and Jim Bartlett pointed out that these problem matches are often near the vendor matching threshold (or your threshold if you’re using GedMatch) and if the threshold is lowered a bit, they continue to match.  They may also be a marginal match on the edge, so to speak or they may have a read error at a critical location in their kit.

What “in common with” matching does is to increase your confidence that these are indeed ancestral matches, a cousin cluster, but it’s not yet triangulation.

Ancestry Matches

Ancestry has added another level of matching into the mix.  The difference is, of course, that you can’t see any segment data at all, at Ancestry, so you don’t have anything other than the fact that you do match the other person and if you have a shakey leaf hint, you also share a common ancestor in your trees.

confidence ancestry matches

When three people match each other on any segment (meaning this does not infer a common segment match) and also share a common ancestor in a tree, they qualify to be a DNA Circle.  However, there is other criteria that is weighted and not every group of 3 individuals who match and share an ancestor becomes a DNA Circle.  However, many do and many Circles have significantly more than three individuals.

confidence Phoebe Crumley circle

This DNA Circle is for Phebe Crumley, one of my Crumley ancestors.  In this grouping, I match one close family group of 5 people, and one individual, Alyssa, all of whom share Phebe Crumley in their trees.  As luck would have it, the family group has also tested at Family Tree DNA and has downloaded their results to GedMatch, but as it stands here at Ancestry, with DNA Circle data only…the only thing I can do is to add them to my match list.

confidence match list 3

In case you’re wondering, the reason I only added three of the 5 family members of the Abija group to my match list is because two are children of one of the members and their Crumley DNA is represented through their parent.

While a small DNA Circle like Phebe Crumley’s can be incorrect, because the individuals can indeed be sharing the DNA of a different ancestor, a larger group gives you more confidence that the relationship to that group of people is actually through the common ancestor whose circle you are a member of.  In the example Circle shown below, I match 6 individuals out of a total of 21 individuals who are all interrelated and share Henry Bolton in their tree.

Confidence Henry Bolton circle

New Ancestor Discoveries

Ancestry introduced New Ancestor Discoveries (NADs) a few months ago.  This tool is, unfortunately, misnamed – and although this is a good concept for finding people whose DNA you share, but whose tree you don’t – it’s not mature yet.

The name causes people to misinterpret the “ancestors” given to them as genuinely theirs.  So far, I’ve had a total of 11 NADS and most have been easily proven false.

Here’s how NADs work.  Let’s say there is a DNA Circle, John Doe, of 3 people and you match two of them.  The assumption is that John Doe is also your ancestor because you share the DNA of his descendants.  This is a critically flawed assumption.  For example, in one case, my ancestors sister’s husband is shown as my “new ancestor discovery” because I share DNA with his descendants (through his wife, my ancestor’s sister.)  Like I said, not mature yet.

I have discussed this repeatedly, so let’s just suffice it to say for this discussion, that there is absolutely no confidence in NADs and they aren’t relevant.

Shared Matches

Ancestry recently added a Shared Matches function.

For each person that you match at Ancestry, that is a 4th cousin or closer and who has a high confidence match ranking, you can click on shared matches to see who you and they both match in common.

confidence ancestry shared matches

This does NOT mean you match these people through the same ancestor.  This does NOT mean you match them on the same segment.  I wrote about how I’ve used this tool, but without additional data, like segment data, you can’t do much more with this.

What I have done is to build a grid similar to the Family Tree DNA matrix where I’ve attempted to see who matches whom and if there is someone(s) within that group that I can identify as specifically descending from the same ancestor.  This is, unfortunately, extremely high maintenance for a very low return.  I might add someone to my match list if they matched a group (or circle) or people that match me, whose common ancestor I can clearly identify.

Shared Matches are the lowest item on the confidence chart – which is not to say they are useless.  They can provide hints that you can follow up on with more precise tools.

Let’s move to the highest confidence tool, triangulation groups.

Triangulation Groups

Of course, the next step, either at 23andMe, Family Tree DNA, through GedMatch, or some combination of each, is to compare the actual segments of the individuals involved.  This means, especially at Ancestry where you have no tools, that you need to develop a successful begging technique to convince your matches to download their data to GedMatch or Family Tree DNA, or both.  Most people don’t, but some will and that may be the someone you need.

You have three triangulation options:

  1. If you are working with the Family Inheritance Advanced at 23andMe, you can compare each of your matches with each other. I would still invite my matches to download to GedMatch so you can compare them with people who did not test at 23andMe.
  2. If you are working with a group of people at Family Tree DNA, you can ask them to run themselves against each other to see if they also match on the same segment that they both match you on. If you are a project administrator on a project where they are all members, you can do this cross-check matching yourself. You can also ask them to download their results to GedMatch.
  3. If your matches will download their results to GedMatch, you can run each individual against any other individual to confirm their common segment matches with you and with each other.

In reality, you will likely wind up with a mixture of matches on your match list and not everyone will upload to GedMatch.

Confirming that segments create a three way match when you share a common ancestor constitutes proof that you share that common ancestor and that particular DNA has been passed down from that ancestor to you.

confidence match list 4

I’ve built this confidence table relative to matches first found at Family Tree DNA, adding matches from Ancestry and following them to GedMatch.  Fortunately, the Abija group has tested at all 3 companies and also uploaded their results to GedMatch.  Some of my favorite cousins!

Spectrum of Confidence

Blaine Bettinger built this slide that sums up the tools and where they fall on the confidence range alone, without considerations of your goals and technical factors such as segment size.  Thanks Blaine for allowing me to share it here.

confidence level Blaine

These tools and techniques fall onto a spectrum of confidence, which I’ve tried to put into perspective, below.

confidence level highest to lowest

I really debated how to best show these.  Unfortunately, there is almost always some level of judgment involved. In some cases, like triangulation at the 3 vendors, the highest level is equivalent, but in other cases, like the medium range, it really is a spectrum from lowest to highest within that grouping.

Now, let’s take a look at our matches that we’ve added to our match list in confidence order.

confidence match list 5

As you would expect, those who triangulated with each other using some chromosome browser and share a common ancestor are the highest confidence matches – those 5 with a red Y.  These are followed by matches who match me and each other but not on the same segment (or at least we don’t know that), so they don’t triangulate, at least not yet.

I didn’t include any low confidence matches in this table, but of the lowest ones that are included, the shakey leaf matches at Ancestry that won’t answer inquiries and the matches at FTDNA who do share a common surname but didn’t download their information to be triangulated are the least confident of the group.  However, even those lower confidence matches on this chart are medium, meaning at Ancestry they are in a Circle and at FTDNA, they do match and share a common surname.  At Family Tree DNA, they may eventually fall into a triangulation group of other descendants who triangulate.

Caveats

As always, there are some gotchas.  As someone said in something I read recently, “autosomal DNA is messy.”

Endogamy

Endogamous populations are just a mess.  The problem is that literally, everyone is related to everyone, because the founder population DNA has just been passed around and around for generations with little or no new DNA being introduced.

Therefore, people who descend from endogamous populations often show to be much more closely related than they are in a genealogical timeframe.

Secondly, we have the issue pointed out by David Pike, and that is when you really don’t know where a particular segment came from, because the segment matches both the parents, or in some cases, multiple grandparents.  So, which grandparent did that actual segment that descended to the grandchild descend from?

For people who are from the same core population on both parent’s side, close matches are often your only “sure thing” and beyond that, hopefully you have your parents (at least one parent) available to match against, because that’s the only way of even beginning to sort into family groups.  This is known as phasing against your parents and while it’s a great tool for everyone to use – it’s essential to people who descend from endogamous groups. Endogamy makes genetic genealogy difficult.

In other cases, where you do have endogamy in your line, but only in one of your lines, endogamy can actually help you, because you will immediately know based on who those people match in addition to you (preferably on the same segment) which group they descend from.  I can’t tell you how many rows I have on my spreadsheet that are labeled with the word “Acadian,” “Brethren” and “Mennonite.”  I note the common ancestor we can find, but in reality, who knows which upstream ancestor in the endogamous population the DNA originated with.

Now, the bad news is that Ancestry runs a routine that removes DNA that they feel is too matchy in your results, and most of my Acadian matches disappeared when Ancestry implemented their form of population based phasing.

Identical by Population

There is sometimes a fine line between a match that’s from an ancestor one generation further back than you can go, and a match from generations ago via DNA found at a comparatively high percentage in a particular population.  You can’t tell the difference.  All you know is that you can’t assign that segment to an ancestor, and you may know it does phase against a parent, so it’s valid, meaning not IBC or identical by chance.

Yes, identical by population segment matching is a distinct problem with endogamy, but it can also be problematic with people from the same region of the world but not members of endogamous populations.  Endogamy is a term for the timeframe we’re familiar with.  We don’t know what happened before we know what happened.

From time to time, you’ll begin to see something “odd” happened where a group of segments that you already have triangulated to one ancestor will then begin to triangulate to a second ancestor.  I’m not talking about the normal two groups for every address – one from your Mom’s side and one from your Dad’s.  I’m talking, for example, when my Mom’s DNA in a particular area begins to triangulate to one ancestral group from Germany and one from France.  These clearly aren’t the same ancestors, and we know that one particular “spot” or segment range that I received from her DNA can only come from one ancestor.  But these segment matches look to be breaking that rule.

I created the example below to illustrate this phenomenon.  Notice that the top and bottom 3 all match nicely to me and to each other and share a common ancestor, although not the same common ancestor for the two groups.  However, the range significantly overlaps.  And then there is the match to Mary Ann in the middle whose common ancestor to me is unknown.

confidence IBP example

Generally, we see these on smaller segment groups, and this is indicative that you may be seeing an identical by population group.  Many people lump these IBP (identical by population) groups in with IBC, identical by chance, but they aren’t.  The difference is that the DNA in an IBP group truly is coming from your ancestors – it’s just that two distinct groups of ancestors have the same DNA because at some point, they shared a common ancestor.  This is the issue that “academic phasing” (as opposed to parental phasing) is trying to address.  This is what Ancestry calls “pileup areas” and attempts to weed out of your results.  It’s difficult to determine where the legitimate mathematical line is relative to genealogically useful matches versus ones that aren’t.  And as far as I’m concerned, knowing that my match is “European” or “Native” or “African” even if I can’t go any further is still useful.

Think about this, if every European has between 1 and 4% Neanderthal DNA from just a few Neanderthal individuals that lived more than 20,000 years ago in Europe – why wouldn’t we occasionally trip over some common DNA from long ago that found its way into two different family lines.

When I find these multiple groupings, which is actually relatively rare, I note them and just keep on matching and triangulating, although I don’t use these segments to draw any conclusions until a much larger triangulated segment match with an identified ancestor comes into play.  Confidence increases with larger segments.

This multiple grouping phenomenon is a hint of a story I don’t know – and may never know.  Just because I don’t quite know how to interpret it today doesn’t mean it isn’t valid.  In time, maybe its full story will be revealed.

ROH – Runs of Homozygosity

Autosomal DNA tests test someplace over 500,000 locations, depending on the vendor you select.  At each of those locations, you find a value of either T, A, C or G, representing a specific nucleotide.  Sometimes, you find runs of the same nucleotide, so you will find an entire group of all T, for example.  If either of your parents have all Ts in the same location, then you will match anyone with any combination of T and anything else.

confidence homozygosity example

In the example above, you can see that you inherited T from both your Mom and Dad.  Endogamy maybe?

Sally, although she will technically show as a match, doesn’t really “match” you.  It’s just a fluke that her DNA matches your DNA by hopping back and forth between her Mom’s and Dad’s DNA.  This is not a match my descent, but by chance, or IBC (identical by chance.)  There is no way for you to know this, except by also comparing your results to Sally’s parents – another example of parental phasing.  You won’t match Sally’s parents on this segment, so the segment is IBC.

Now let’s look at Joe.  Joe matches you legitimately, but you can’t tell by just looking at this whether Joe matches you on your Mom’s or Dad’s side.  Unfortunately, because no one’s DNA comes with a zipper or two sides of the street labeled Mom and Dad – the only way to determine how Joe matches you is to either phase against Joe’s parents or see who else Joe matches that you match, preferable on the same segment – in other words – create either a match or ICW group, or triangulation.

Segment Size

Everyone is in agreement about one thing.  Large segments are never IBC, identical by chance.  And I hate to use words like never, so today, interpret never to mean “not yet found.”  I’ve seen that large segment number be defined both 13cM and 15cM and “almost never” over 10cM.  There is currently discussion surrounding the X chromosome and false positives at about this threshold, but the jury is still out on this one.

Most medium segments hold true too.  Medium segment matches to multiple people with the same ancestors almost always hold true.  In fact, I don’t personally know of one that didn’t, but that isn’t to say it hasn’t happened.

By medium segments, most people say 7cM and above.  Some say 5cM and above with multiple matching individuals.

As the segment size decreases, the confidence level decreases too, but can be increased by either multiple matches on that segment from a common proven ancestor or, of course, triangulation.  Phasing against your parent also assures that the match is not IBD.  As you can see, there are tools and techniques to increase your confidence when dealing with small segments, and to eliminate IBC segments.

The issue of small segments, how and when they can be utilized is still unresolved.  Some people simply delete them.  I feel that is throwing the baby away with the bathwater and small segments that triangulate from a common ancestor and that don’t find themselves in the middle of a pileup region that is identical by population or that is known to be overly matchy (near the center of chromosome 6, for example) can be utilized.  In some cases, these segments are proven because that same small segment section is also proven against matches that are much larger in a few descendants.

Tim Janzen says that he is more inclined to look at the number of SNPs instead of the segment size, and his comfort number is 500 SNPs or above.

The flip side of this is, as David Pike mentioned, that the fewer locations you have in a row, the greater the chance that you can randomly match, or that you can have runs of heterozygosity.

No one in our discussion group felt that all small segments were useless, although the jury is still out in terms of consensus about what exactly defines a small segment and when they are legitimate and/or useful.  Everyone of us wants to work towards answers, because for those of us who are dealing with colonial ancestors and have already picked the available low hanging fruit, those tantalizing small segments may be all that is left of the ancestor we so desperately need to identify.

For example, I put together this chart detailing my matching DNA by generation. Interesting, I did a similar chart originally almost exactly three years ago and although it has seemed slow day by day, I made a lot of progress when a couple of brick walls fell, in particular, my Dutch wall thanks to Yvette Hoitink.

If you look at the green group of numbers, that is the amount of shared DNA to be expected at each level.  The number of shared cMs drops dramatically between the 5th and 6th generation from 13 cM which would be considered a reasonable matching level (according to the above discussion) at the 5th generation, and 3.32 cM at the 6th generation level, which is a small segment by anyone’s definition.

confidence segment size vs generation

The 6th generation was born roughly in 1760, and if you look to the white grouping to the right of the green group, you can see that my percentage of known ancestors is 84% in the 5th generation, 80% in the 6th generation, but drops quickly after that to 39, 22 and 3%, respectively.  So, the exact place where I need the most help is also the exact place where the expected amount of DNA drops from 13 to 3.32 cM.  This means, that if anyone ever wants to solve those genealogical puzzles in that timeframe utilizing genetic genealogy, we had better figure out how to utilize those small segments effectively – because it may well be all we have except for the occasional larger sticky segment that is passed intact from an ancestor many generations past.

From my perspective, it’s a crying shame that Ancestry gives us no segment data and it’s sad that 23andMe only gives us 5cM and above.  It’s a blessing that we can select our own threshold at GedMatch.  I’m extremely grateful that FTDNA shows us the small segment matches to 1cM and 500 SNPs if we also match on 20cM total and at least one segment over 7cM.  That’s a good compromise, because small segments are more likely to be legitimate if we have a legitimate match on a larger segment and a known ancestor.  We already discussed that the larger the matching segment, the more likely it is to be valid. I would like to see Family Tree DNA lower the matching threshold within projects.  Surname projects imply that a group of people will be expected to match, so I’d really like to be able to see those lower threshold matches.

I’m hopeful that Family Tree DNA will continue to provide small segment information to us.  People who don’t want to learn how to use or be bothered with small segments don’t have to.  Delete is perfectly legitimate option, but without the data, those of us who are interested in researching how to best utilize these segments, can’t.  And when we don’t have data to use, we all lose.  So, thank you Family Tree DNA.

Coming Full Circle

This discussion brings us full circle once again to goals.

Goals change over time.

My initial reason for testing, the first day an autosomal test could be ordered, was to see if my half-brother was my half-brother.  Obviously for that, I didn’t need matching to other people or triangulation.  The answer was either yes or no, we do match at the half-sibling level, or we don’t.

He wasn’t.  But by then, he was terminally ill, and I never told him.  It certainly explained why I wasn’t a transplant match for him.

My next goal, almost immediately, was to determine which if either my brother or I were the child of my father.  For that, we did need matching to other people, and preferably close cousins – the closer the better.  Autosomal DNA testing was new at that time, and I had to recruit cousins.  Bless those who took pity on me and tested, because I was truly desperate to know.

Suffice it to say that the wait was a roller coaster ride of emotion.

If I was not my father’s child, I had just done 30+ years of someone else’s genealogy – not a revelation I relished, at all.

I was my father’s child.  My brother wasn’t.  I was glad I never told him the first part, because I didn’t have to tell him this part either.

My goal at that point changed to more of a general interest nature as more cousins tested and we matched, verifying different lineages that has been unable to be verified by Y or mtDNA testing.

Then one day, something magical happened.

One of my Y lines, Marcus Younger, whose Y line is a result of a NPE, nonparental event, or said differently, an undocumented adoption, received amazing information.  The paternal Younger family line we believed Marcus descended from, he didn’t.  However, autosomal DNA confirmed that even though he is not the paternal child of that line, he is still autosomally related to that line, sharing a common ancestor – suggesting that he may have been born of a Younger female and given that surname, while carrying the Y DNA of his biological father, who remains unidentified.

Amazingly, the next day, a match popped up that matched me and another Younger relative.  This match descended not from the Younger line, but from Marcus Younger’s wife’s alleged surname family.  I suddenly realized that not only was autosomal DNA interesting for confirming your tree – it could also be used to break down long-standing brick walls.  That’s where I’ve been focused ever since.

That’s a very different goal from where I began, and my current goal utilizes the tools in a very different way than my earlier goals.  Confidence levels matter now, a great deal, where that first day, all I wanted was a yes or no.

Today, my goal, other than breaking down brick walls, is for genetic genealogy to become automated and much easier but without taking away our options or keeping us so “safe” that we have no tools (Ancestry).

The process that will allow us to refine genetic genealogy and group individuals and matches utilizing trees on our desktops will ultimately be the key to unraveling those distant connections.  The data is there, we just have to learn how to use it most effectively, and the key, other than software, is collaboration with many cousins.

Aside from science and technology, the other wonderful aspect of autosomal DNA testing is that is has the potential to unite and often, reunite families who didn’t even know they were families.  I’ve seen this over and over now and I still marvel at this miracle given to us by our ancestors – their DNA.

So, regardless of where you fall on the goals and matching confidence spectrum in terms of genetic genealogy, keep encouraging others to test and keep reaching out and sharing – because it takes a village to recreate an ancestor!  No one can do it alone, and the more people who test and share, the better all of our chances become to achieve whatever genetic genealogy goals we have.

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Demystifying Autosomal DNA Matching

dna word cluster4

What, exactly, is an autosomal DNA match?

Answer:  It’s Relative

I’m sorry, I just had to say that.

But truthfully, it is.

I know this sounds like a very basic question, and it is, but the answer sometimes isn’t as straightforward as we would like for it to be.

Plus, there are differences in quality of matches and types of matches.  If you want to sigh right about now, it’s OK.

We’ve talked a lot about matching in various recent articles.  I have several people who follow this blog religiously, and who would rather read this than, say, do dishes (who wouldn’t).  One of our regulars recently asked me the question, “what, exactly, is a match and how do I tell?”

Darned good question and I wish someone had explained this to me so I wouldn’t have had to figure it out.

In the computer industry, where I spent many years, we have what we call flow charts or wernier diagrams which in essence are logic paths that lead to specific results or outcomes depending on the answers at different junctions.

flow chart

I had a really hard time deciding whether to use the beer decision-making flow chart or the procrastinator flow chart, but the procrastinator flow chart was just one big endless loop, so I decided on the beer.

What I’m going to do is to step you through the logic path of finding and evaluating a match, determining whether it’s valid, identical by descent or chance, when possible, and how to work with your matches and what they mean.

Let me also say that while I use and prefer Family Tree DNA, these matching techniques are universal and apply to results from 23andMe as well, but not for Ancestry who gives you no browser or tools to compare your DNA to anyone else.  So, you can’t compare your results at Ancestry.

Comparing DNA results is the lynchpin of genetic genealogy.  You’re dead in the water without it.  If you have tested at Ancestry, you can always transfer your results to Family Tree DNA, where you do have tools, and to GedMatch as well.  You’re always better, in terms of genealogy, to fish in as many ponds as possible.

Before we talk about how to work with matches, for those who need to figure out how to find matches at Family Tree DNA and 23andMe, I wrote about that in the Chromosome Browser War article.  This article focuses on working with matching DNA after you have found that you are a match to someone – and what those matches might mean.

Matching Thresholds

All autosomal DNA vendors have matching thresholds.  People who meet or exceed those thresholds will be shown on your match list.  People who do not meet the initial threshold will not be considered as a match to you, and therefore will not be on your match list.

Currently, at Family Tree DNA, their match threshold to be shown as a match is about 20cM of total matching DNA and a single segment of about 7.7cM with 500 SNPs or over. The words “about” are in there because there is some fuzziness in the rules based on certain situations.

After you meet that criteria and you are shown as a match to an individual, when you download your matching data, your matches to them on each chromosome will be shown to the 1cM and 500 SNP level

At 23andMe, the threshold is 7cMs/700 SNPs for the first segment.  However, 23andMe has an upper limit of people who can match you at about 1000 matches.  This can be increased by the number of people you are communicating or sharing with.  However, your smallest matches will be dropped from your list when you hit your threshold.  This means that it’s very likely that at least some of your matches are not showing if you have in excess of 1000 matches total.  This means that your personal effective cM/SNP match threshold at 23andMe may be much higher.

Step 1 – Downloading Your Matching Segments

For this comparison, I’m starting with two fresh files from Family Tree DNA, one file of my own matches and one of my mother’s matches.  My mother died before autosomal DNA testing was available, so her results are only at Family Tree DNA (and now downloaded to GedMatch,) because her DNA was archived there.  Thank you Family Tree DNA, 100,000 times thank you!!!

At Family Tree DNA, the option to download all matches with segment information is on the chromosome browser tab, at the top, at the right, shown below.

ftdna download button

If you have your parents DNA available to test and it hasn’t been tested, order a kit for them today.  If either or both parents have been tested, download their results into the same spreadsheet with yours and color code them in a way you will understand.

In my case, I only have my mother’s results, and I color coded my matches pink, because I’m the daughter.  However, if I had both parents, I might have colored coded Mother pink and Dad blue.

Whatever color coding you do, it’s forever in your master spreadsheet, so make a note of what it is.  In my case, it’s part of the match column header.  Why is it in my column header?  Because I screwed up once and reversed them in a download.

Step 2 – Preparing and Sorting Your Spreadsheet

In my master DNA spreadsheet, I have the following columns,

dna master header

The green cell matches are matches to me from 23andMe.  My cousin, Cheryl also tested at 23andMe before autosomal testing was offered at Family Tree DNA.

The Source column, in my spreadsheet, means any source other than FTDNA.  The Ignore column is an extraneous number generated at one time by downloads.  I could delete that column now.

The “Side” column is which side the match is from, Mom or Dad.  Mom’s I can identify easily, because I have her DNA to compare to.  I don’t identify a match as Dad’s without having identified an ancestral line, because I don’t have his DNA to compare to.

And no, you can’t just assume that if it doesn’t match Mom, it’s an automatic match to Dad because you may have some IBS, identical by chance, matches.

The Common Ancestors/Comments column is just that.  I include things like when I e-mailed someone, if the match is triangulated and if so, with whom, etc.

In my master spreadsheet, the first “name” column (of who tested) is deleted, but I’ve left it in the working spreadsheet (below) with my mother for illustration purposes.  That way, neither of us has to remember who is pink!

Step 3 – Reviewing IBD and IBS Guidelines

If you need a refresher on, phasing, IBD, identical by descent, IBS which can mean either identical by chance or identical by population, it would be a good time to read or reread the article titled How Phasing Works and Determining IBD Versus IBS Matches.

Let’s briefly review the IBD vs IBS guidelines, because we’ll be applying them in this article.

Identical by Chance – Can be determined if an individual you match does not match to one of your parents, if parents are available.  If parents are not available for matching, IBS by chance segments won’t triangulate with other known genealogical matches on a common segment.

Identical by Descent – Can be suggested if a common ancestor (or ancestral line) can be determined between any two people who are not known relatives. If the two people are known close relatives, and their DNA matches, identical by descent is proven.  IBD can be proven with previously unknown family or genealogical matches when any three people descending from that same ancestor or ancestral line all match each other on the same segment of DNA.  Three way matching is called triangulation.

Identical by Population – Can be determined when multiple people triangulate with you on a specific segment of DNA, but the triangulated groups are from proven different lineages and are not otherwise related.  This is generally found in smaller segments from similar regions of the world.  Identical by population is identical by descent, but the ancestors are so far back in time that they cannot be determined and may contribute the same DNA to multiple lineages.  This is particularly evident in Jewish genealogy and other endogamous groups.

Step 4 – Determining Parental Side and IBS by Chance

The first thing to do, if you have either or both parents, is to determine whether your matches phase to your parents or are IBS by chance.

In this context, phasing means determining whether a particular match is to your father’s side of the family or to your mother’s side of the family.

Remember, at every address in your DNA, you will have two valid matches to different lines, one from your mother and one from your father.  The address on your DNA consists of the chromosome number which equates to the street name, and then the start and end locations, which consists of a range of addresses on that street.  Think of it as the length of your property on the street.

First, let’s look at my situation with only my mother’s DNA for comparison.

It’s easy to tell one of three things.

  1. Do mother and I both match the person? If so, that means that DNA match is from mother’s side of the family. Mark it as such. They are green, below.
  2. If the individual does not match me and mother, both, and only matches me, then the match is either on my father’s side or it’s IBS by chance. Those matches are blue below. Because I don’t have my father’s DNA, I can’t tell any more at this step.
  3. Notice the matches that are Mom’s but not to me. That means that I did not receive that DNA from Mom, or I received a small part, but it’s not over the lowest matching threshold at Family Tree DNA of 1cM and 500 SNPs.

match mom

In this next scenario, you can see that mother and I both match the same individual, but not on all segments.  I selected this particular match between me, my mother and Alfred because it has some “problems” to work through.

match mom2

The segments shown in green above are segments that Mom carries that I don’t.  This means that I didn’t receive them from mother.  This also means they could be  matching to Alfred legitimately, or are IBS by chance.  I can’t tell anything more about them at this point, so I’ve just noted what they are.  I usually mark these as “mother only” in my master spreadsheet.

match mom3

The first of the two green rows above show a match but it’s a little unusual.  My segment is larger than my mothers.  This means that one of five things has happened.

  1. Part of this segment is a valid match.  At the end, where we don’t match, the match extends IBS by chance a bit at the end, in my case, when matching Alfred. The valid match portion would end where my mother’s segment ends, at 16,100,293
  2. There is a read error in one of the files.
  3. The boundary locations are fuzzy, meaning vendor calculations like ‘healing’ for no calls, etc..
  4. I also match to my father’s line.
  5. Recombination has occurred, especially possible in an endogamous population, reconnecting identical by population segments between me and Alfred at the end of the segment where I don’t match my mother’s segment, so from 16,100,293 to 16,250,884.

Given that this is a small segment, the most likely scenario would be the first, that this is partly valid and partly IBS by chance.  I just make the note by that row.

The second green segment above isn’t an exact match, but if my segment “fits within” the boundaries of my mother’s segments, then we know I inherited the entire segment from her.  Once again, my boundaries are off a bit from hers, but this time it’s the beginning.  The same criteria applies as in 1-5, above.

match mom4

The green segments above are where I match Alfred, but my mother does not.  This means that these segments are either IBS by chance or that they will match my father.  I don’t know which, so I simply label them.  Given that they are all small segments, they are likely IBS by chance, but we don’t know that.  If we had my father’s DNA, we would be able to phase against him, too, but we don’t.

Now, if I was to leave this discussion here, you might have the impression that all small segment matches have problems, but they don’t.  In fact, here’s a much more normal “rea life” situation where mother and I are both matching to our cousin, Cheryl, Mom’s first cousin.  These matches include both large and small segments.  Let’s take a look and see what we can tell about our matches.

match mom complete

Roberta and Barbara have a total of 83 DNA matches to Cheryl.

Some matches will be where Barbara matches Cheryl and Roberta doesn’t.  That’s normal, Barbara is Roberta’s mother and Roberta only inherits half of Barbara’s DNA.  These rows where only Barbara, the mother, matches Cheryl are not colorized in the Start, End, cM and SNP columns, so they show as white.

Some matches will be exact matches.  That too is normal.  In some cases, Barbara passes all of a particular segment of DNA to Roberta.  These matches are colored purple.

Some of these matches are partial matches where Roberta inherited part of the segment of DNA from Barbara.  These are colored green. There are two additional columns at right where the percentage of DNA that Roberta inherited from Barbara on these segments is calculated, both for cM and SNPs.

Some of the matches are where Roberta matches Cheryl and Barbara doesn’t.  Cheryl is not known to be related to Roberta on her father’s side, so assuming that statement is correct, these matches would be IBS, identical by state, meaning identical by chance and can be disregarded at legitimate matches.  These are colored rust.  Note that most of these are small segments, but one segment is 8.8cM and 2197 SNPs.  In this case, if this segment becomes important for any reason, I would be inclined to look at the raw data file of Barbara to see if there were no calls or a problem with reads in this region that would prevent an otherwise legitimate match.

Let’s look at how these matches stack up.

Number Percent (rounded) Comment
Exact Matches 26 31 100% of the DNA
Barbara Only 20 24 0% of the DNA
Partial Matches 29 35 11-98% of the actual DNA matches
Roberta Only (IBS by chance) 7 8 Not a valid match

I think it’s interesting to note that while, on the average, 50% of the DNA of any segment is passed to the child, in actuality, in this example of partial inheritance, meaning the green rows, inheritance was never actually 50%.  In fact, the SNP and cM percentages inherited for the same segment varied, and the actual amounts ranged from 11-98% of the DNA of the parent being inherited by the child.  The average of these events was 54.57143 (cM) and 54.21429 (SNPs) however.

On top of that, in 13 (26 rows) instances, Roberta inherited all of Barbara’s DNA in that sequence, and in 20 cases, Roberta inherited none of Barbara’s DNA in that sequence.

This illustrates that while the average of something may be 50%, none of the actual individual values may be 50% and the values themselves may include the entire range of possibilities.  In this case, 11-98% were the actual percentage ranges for partial matches.

Matching Both Parents

I don’t have my father’s DNA, but I’m creating this next example as if I did.

match both parents

Matches to mother are marked in green.

I have two matches where I match my father, so we can attribute those to his side, which I’ve done and marked in orange.

The third group of matches to me, at the bottom, to Julio, Anna, Cindy and George don’t match either parent, so they must be IBS by chance.

I label IBS by chance segments, but I don’t delete them because if I download again, I’ll have to go through this same analysis process if I don’t leave them in my spreadsheet

Step 5 – How Much of the DNA is a Match?

One person asked, “exactly how do I tell how much DNA is matching, especially between three people.”  That’s a very valid question, especially since triangulation requires matching of three people, on the same segment, proven to a common ancestral line.

Let’s look at the match of both me and my mother to Don, Cheryl and Robin.

match mom part

In this example, we know that Don, Cheryl and Robin all match me on my mother’s side, because they all three match me and my mother, both on the same segment.

How do we determine that we match on the same segment?

I have sorted this spreadsheet in order of end location, then start location, then chromosome number so that the entire spreadsheet is in chromosome order, then start location, then end location.

We can see that both mother and I match Cheryl partially on this segment of chromosome 1, but not exactly.  The start location is slightly different, but the end location matches exactly.

The area where we all three match, meaning me, Mom and Cheryl, begins at 176,231,846 and ends at the common endpoint of 178,453,336

On the chart below, you can see that mother and I also both match Don, Cheryl’s brother, on part of this same segment, but not all of the same segment.

match mom part2

The common matching areas between me, Mom and Don begins at 176,231,846 and ends at 178,453,336.

Next, let’s look at the third person, Robin.

Mom and I both match Robin on part of this same overlapping segment as well.  Note that my segment extends beyond Mom’s, but that does not invalidate the portion that does match between Robin, Mom and I.

match mom part3

Our common match area begins at the same location, but ends at 178,453,336, the same location as the common end area with Don and Cheryl

Step 6 – What Do Matches Mean? IBD vs IBS in Action

So, let’s look at various types of matches and what they tell us.

match mom example

Looking at our matching situation above, let’s apply the various IBD/IBS rules and guidelines and see what we have

1. Are these matches identical by chance?  No.  How do we know?

a. Because they all match both me and a parent.

2. Are these matches identical by descent? Yes. How do we know?

a. Because we all match each other on this segment, and we know the common ancestor of Cheryl, Don, Barbara and me is Hiram Ferverda and Evaline Miller.  We know that Robin descends from the same ancestral Miller line.

3. Are these matches identical by population.  We don’t know, but there is no reason at this point to think so. Why?

a. Because looking at my master spreadsheet, I see no evidence that these segments are also assigned to other lineages. These individuals are also triangulated on a large number of other, much larger, segments as well.

4. Are these matches triangulated, meaning they are proven to a common ancestor? Yes. How do we know?

a. Documented genealogy of Hiram Ferverda and Evaline Miller. Don, Barbara, Cheryl and me are known family since birth.
b. Documented genealogy of Robin to the same ancestral family, even though Robin was previously unknown before DNA matching.
c. Even without the documented genealogy, Robin matches a set of two triangulation groups of people documented to the same ancestral line, which means she has to descend from that same line as well.

In our case, clearly these individuals share a common ancestor and a common ancestral line.  Even though these are small segments on chromosome 1, there are much larger matching segments on other chromosomes, and the same rules still apply.  The difference might be at some point smaller segments are more likely to be identical by population than larger segments.  Larger segments, when available, are always safer to use to draw conclusions.  Larger groups of matching individuals with known common genealogy on the same segments are also the safest way to draw conclusions.

Step 7 – Matching With No Parents

Sometimes you’re just not that lucky.  Let’s say both of your parents have passed and you have no DNA from them.

That immediately eliminates phasing and the identical by chance test by comparing to your parents, so you’ll have to work with your matches, including your identical by chance segments.

A second way to “phase” part of your DNA to a side of your family is by matching with known cousins or any known family member.

In the situation above, matching to Cheryl, Don and Robin, let’s remove my mother and see what we have.

match no mom

In this case, I still match to both of my first cousins, once removed, Cheryl and Don.  Given that Cheryl and Don are both known cousins, since forever, I don’t feel the need for triangulation proof in this case – although the three of us are triangulated to our common ancestor.  In other words, the fact that my mother does match them at the expected 1st cousin level is proof enough in and of itself if we only had one cousin to test.  We know our common ancestor is Cheryl and Don’s grandparents, who are my great-grandparents, Hiram Ferverda and Evaline Miller.

When I looked at Robin’s pedigree chart and saw that Robin descended from Philip Jacob Miller and wife Magdalena, I knew that this segment was a Miller side match, not a Ferverda match.

Therefore, matching with someone whose genealogy goes beyond the common ancestor of Cheryl, Don and me proves this line through 4 more generations.  In other words, this DNA segment came through the following direct line to reach Me, Mother, Cheryl and Don.

  • Philip Jacob Miller and Magdalena
  • Daniel Miller
  • David Miller
  • John David Miller
  • Evaline Louise Miller who married Hiram Ferverda

Clearly, we know from the earlier chart that my mother carried this DNA too, but even if we didn’t know that, she obviously had to have carried this segment or I would not carry it today.

So, even though in this example, our parents aren’t directly available for IBS testing and elimination, we can determine that anyone who matches both me and Cheryl or me and Don will have also matched mother on that segment, so we have, in essence, phased those people by triangulation, not by direct parental matching.

Step 8 – Triangulation Groups

What else does this match group tell us?

It tells us that anyone else who matches me and any one of our triangulation group on that segment also descends from the Miller descendant clan, one way or another.

Why do they have to match me AND one of the triangulation group members on that segment?  Because I have two sides to my DNA, my Mom’s side and my Dad’s side.  Matching me plus another person from the triangulation group proves which side the match is on – Mom’s or Dad’s.

We were able to phase to eliminate any identical by chance segments people on Mom’s side, so we know matches to both of us are valid.

On Dad’s side, there are some IBS by chance people (or segments) thrown in for good measure because I don’t have my Dad’s DNA to eliminate them out of the starting gate.  Those IBS segments will have to be removed in time by not triangulating with proven triangulated groups they should triangulate with, if they were valid matches.

When you map matches on your chromosome spreadsheet, this is what you’re doing.  Over time, you will be able to tell when you receive a new match by who they match and where they fall on your spreadsheet which ancestral line they descend from.

GedMatch also includes a triangulation utility.  It’s a great tool, because it produces trios of people for your top 400 matches.  The results are two kits that triangulate to the third person whose kit number you are matching against.

The output, below, shows you the chromosome number followed by the two kit numbers (obscured) that triangulate at this location, and then the start and end location followed by the matching cMs.  The result is triangulation groups that “slide to the right.”

gedmatch triang group3

In the example above, all of the triangulation matches to me above the red arrow include either Mother, my Ferverda cousins or the Miller group that we discussed in the Just One Cousin article.  In other words they are all related via a common ancestor.

You can tell a great deal about triangulation groups by who is, and isn’t in them using deductive reasoning.  And once you’ve figured out the key to the group, you have the key to the entire group.

In this case, Mom is a member of the first triangulation group, so I know this group is from her side and not Dad’s side.  Both Ferverda cousins are there, so I know it’s Mom’s Dad’s side of the family.  The Miller cousins are there, so I know it’s the Miller side of Mom’s Dad’s side of the family.

Please also note that while this entire group triangulates within itself, that the group manages to slide right and the first triangulated group of 3 in the list may not overlap the DNA of the last triangulated group of 3.  In fact, because you can see the start and end points, you can tell that these two triangulated groups don’t overlap.  The multiple triangulation groups all do match some portion of the group above and below them (in this case,) and as a composite group, they slide to the right. Because each group overlaps with the group above and below them, they all connect together in a genetic chain.  Because there is an entire group that are triangulated together, in multiple ways, we know that it is one entire group.

This allows me to map that entire segment on my Mom’s side of my DNA, from 10,369,154 to 41,685,667 to this group because it is contiguously connected to me, triangulated and unbroken.  The most distant ancestor listed will vary based upon the known genealogy of the three people being triangulated  For example, part of this segment, may come from Philip Jacob Miller himself, the line’s founder,, but another part could come from his son’s wife, who is also my ancestor.  Therefore, the various pieces of this group segment may eventually be attributed to different ancestors from this particular line based upon the oldest common ancestor of the three people who have triangulated.

In our example above, the second group starts where the red arrow is pointing.  I have absolutely no idea which ancestor this second group comes from – except – I know it does not come from my mother’s side because her kit number isn’t there.

Neither are any of my direct line Estes or Vannoy relatives, so it’s probably not through that line either.  My Bolton cousins are also missing, so we’ve probably eliminated several possible lines, 3 of 4 great grandparents, based on who is NOT in the match group.  See the value of testing both close and distant cousins?  In this case, the family members not only have to test, they also have to upload their results to GedMatch.

Conversely, we could quickly identify at least a base group by the presence in the triangulation groups of at least one my known cousins or people with whom I’ve identified my common ancestor.  Two from the same line would be even better!!!

Endogamy

The last thing I want to show you is an example of what an endogamous group looks like when triangulated.

gedmatch endogamy

This segment of chromosome 9 is an Acadian matching group to my Mom – and the list doesn’t stop here – this is just the size of the screen shot.  These matches continue for pages.

How do I know this group is Acadian?  In part, because this group also triangulates with my known Lore cousin who also descends from the same Acadian ancestor, Antoine Lore, son of Honore Lore and Marie Lafaille.  Additionally, I’ve worked with some of these people and we have confirmed Honore Lore and Marie Lafaille as our common ancestor as well.  In other cases, we’ve confirmed upstream ancestors.

Unfortunately, the Acadians are so intermarried that it’s very difficult to sort through the most distant genetic ancestor because there tend to be multiple most distant ancestors in everyone’s trees.  There is a saying that if you’re related to one Acadian, you’re related to all Acadians and it’s the truth.  Just ask my cousin Paul who I’m related to 137 different ways.

Matches to endogamous groups tend to have very, very long lists of matches, even triangulated, which means proven, matches.

Oh, and by the way, just for the record, this lengthy group includes some of my proven Acadian matches that were trimmed, meaning removed, from my match list when Ancestry did their big purge due to their new and improved phasing.  So if there was ever any doubt that we did in fact lose at least some valid matches, the proof lies right here, in the triangulation of those exact same people at GedMatch

Summary

I hope this step by step article has helped take the Greek, or maybe the geek, out of matching.  Once you think of it in a step by step logical basis, it makes a lot of sense and allows you to reasonably judge the quality of your matches.

The rule of thumb has been that larger matches tend to be “legitimate” and smaller matches are often discarded en masse because they might be problematic.  However, we’ve seen situations where some larger matches may not be legitimate and some smaller matches clearly are.  In essence, the 50% average seldom applies exactly and rules of thumb don’t apply in individuals situations either.  Your situation is unique with every match and now you have tools and guidelines to help you through the matching maze.

And hey, since we made it to the end, I think we should celebrate with that beer!!!

beer

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Disclosure

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

Thank you so much.

DNA Purchases and Free Transfers

Genealogy Services

Genealogy Research

Just One Cousin

Recently, someone wrote to me and said that they thought the autosomal DNA matching between groups of family members was wonderful, but they have “just one first cousin” and feel left out.  So, I decided to see what could be done with just two cousins.  In this case, the two cousins are full siblings and both first cousins to my mother, Barbara.  This would be the same process whether there was one or two cousins, since the two are siblings. Utilizing two cousins who are siblings just gives me the advantage of additional matching and triangulation capabilities.

This does presume that both people involved are willing to share and do a bit of comparison work on their various DNA accounts.  In other words, you can’t do this by yourself without cooperation from your cousin.

Here’s the common ancestor of our testers.

Miller Ferverda chart

Barbara, Cheryl and Don took a Family Finder autosomal DNA test at Family Tree DNA.

The DNA shared by Barbara, Cheryl and Don is from their common ancestral couple, Hiram B. Ferverda and Evaline Louise Miller.

Some of that shared DNA will be Hiram’s Ferverda DNA and some will be Evaline’s Miller DNA.  The only way to differentiate between the Ferverda and Miller DNA is to test people who are only Ferverda or only Miller, descendants of people upstream of Hiram and Evaline, and if there are any common segments between the testers and those Ferverda or Miller individuals, you can then assign that DNA segment to that side of the family – Miller or Ferverda.

I’m using Barbara’s chromosome as the “match to” background, below.  Cheryl, in orange, and Don, in blue, are shown as matches to Barbara.  You can see that these three people share a lot of their grandparents DNA.  You can also see where Don and Cheryl didn’t inherit the same DNA from their father, in some instances, like on chromosome 1 below, where Cheryl (orange) matches Barbara on a much larger part of the chromosome than Don does (blue.)  But then look at chromosome 13 where Barbara and Don match on a huge segment and Cheryl, just a small portion.  Don and Cheryl inherited different DNA from their parents at these locations.

Two cousins browser

The three testers’ common DNA segments on chromosome 1 are shown in the table below.  I’ve colored Cheryl’s pink and her brother, Don’s, blue.  You can see that Barbara matches some segments with Don that Cheryl didn’t inherit from her parents.  All of the DNA Barbara matches with Cheryl on this chromosome is also matched, at least in part, in that location, with Don.  The chart below, matches the graphic above, for chromosome 1 and is the “view data in a table” option on the chromosome browser as well as the leftmost “download to excel” option.  The download to excel option at right downloads all of the matches for the individual, not just the ones currently showing in the chromosome browser.

Two cousins combined

When at least two known relatives have tested, we have something to compare against.  In this case, we have a total of 3 people, 2 siblings and a first cousin, before we start matching outside known family.  We don’t know which of their shared DNA comes from which ancestor, but we can now look for people who match Barbara and at least Cheryl OR Don which proves a common ancestor between the three individuals.  Matching Barbara, Cheryl AND Don would be even better.

The gold standard for DNA matching, called triangulation, that proves a particular segment to a specific ancestor is as follows.

  • All (at least 2) people match you on the same segment.
  • Those people also match each other on the same segment.
  • Meaning, at least three people with a known common ancestral line must match on the same segment.

The key word here is “on the same segment”.

The next thing to do is to find out which of Barbara’s, Cheryl’s and Don’s matches are “in common with” each other.  This means Barbara, Cheryl and Don all share a matching segment with these other people, but without additional analysis, we can’t determine whether they share a match on the same segment or not.

I ran Barbara “in common with” Cheryl and you can see that the first two people returned on that match list were me and Don because matches are listed in the order of the largest cM of shared data first.  The “in common with” tool is the blue crossed arrows, below.

Two cousins ICW

Next I ran Barbara in common with Don.

There were a total of 43 people in common with Cheryl and 49 with Don.

I downloaded the matching individuals (download link at the bottom right of the match page) and sorted them in a spreadsheet to see who matches whom. Here’s what the first part of my spreadsheet looks like (sorted in chromosome and segment order.)  I colorized the rows by cousin for easier visualization.

Two cousins match example

We have 92 total matching individuals in common with Barbara and Cheryl and then Barbara and Don.  A total of 19 people are listed as matching BOTH Cheryl and Don (for a total of 38 rows in the spreadsheet), so that means that there are 54 people who are in common with either Barbara and Cheryl or Barbara and Don, but not in common with all 3, Barbara AND Cheryl AND Don.  This illustrates how differently siblings inherit DNA from their parents and how it affects matches another generation later.

In Common With Matches To both Don and Cheryl To Cheryl only or Don only, but not both
Barbara 19 (38 rows of 92) 54

Clearly, the people who match all three individuals, Barbara, Cheryl and Don are likely the closest relatives.

So let’s focus on those closest matching people.  If you were utilizing only one cousin here, you would simply utilize every “in common with” match between two individuals and move forward.  Because I have siblings here, and because I don’t want to deal with 72 different people, I’m using the fact that they are siblings to focus my efforts on the most closely related matches – people who match Barbara AND both siblings.  You could also limit your focus by something like a common ancestral surname between all match members.

The next step is for each tester, meaning Barbara, Cheryl and Don, to compare each individual on the common match list to their DNA.  This means that Barbara, Cheryl and Don all three will compare to all 18 individuals.  We now have only 18 matching people, instead of 19, because I removed my own matches, since mine are a subset of Barbara’s.  Checking to see how each of our testers matches each common matching person is the only way to determine that there is a three (or 4) way triangulation that will confirm a common ancestor.

There are two ways to do this at Family Tree DNA.

1. You can, 5 matches at a time, compare in the chromosome browser, then download only the matching segments to a spreadsheet for those 5 individuals. This means 4 sets of matches for each of three people.

Two cousins browser download

2. You can download Barbara, Cheryl and Don’s entire segment match list and then eliminate the matches that aren’t relevant to the discussion – meaning everyone except the 18 common matches between the three people.

The download option for the entire segment match list for the person whose kit you are looking at is shown at the top of the chromosome browser, to the right.  Downloading the currently showing individuals matching segments is shown at the top of the chromosome browser, to the left.

Because we can only push 5 people at a time to the chromosome browser, in this case, it will be easier to simply download all of the matches for each of the three individuals and then put them into a common spreadsheet and sort by the names we determined match in common between all three cousins.

I downloaded all of the matches for Barbara, Cheryl and Don, colorized them and then sorted them in the spreadsheet by the name of who they matched.  I then searched for the names of the 18 individuals who matched Barbara, Cheryl and Don, and copy/pasted them into a separate spreadsheet.

I could then sort the 18 matching individuals results by chromosome and start and end location.

two cousin matches

Barbara’s DNA matches are white rows, Cheryl’s are pink and Don’s are blue.

The segments where Barbara, Don and Cheryl all match more than one other person on an overlapping area of their DNA segments are colorized green.  This means that 4 or more people match on that same identical segment, the three known cousins and at least one other person.

The segments where at least Barbara and either Don or Cheryl (but not both) match at least one other person are colorized yellow. This means that least three people match on that same segment.

Since the gold standard of triangulation is 3 individuals matching on the same segment, both the yellow and green segments contain matches that fall into this category and are triangulated.  All of those segments match at least two of the cousins, who match each other, plus in some cases, additional people too.

Let’s walk through one triangulation sequence.

In the green cluster, above, you can see that Barbara, Cheryl and Don all match Arthur on overlapping portions of the same segment.  The overlapping portion between all 3 individuals and Arthur runs from 49,854,186 to 53,551,492.  In addition, both Don and Cheryl match Tiffany on part of that same segment and Barbara matches Dean on part as well.  These segments aren’t exactly the same for any of the cousins, with different amounts of matching DNA as reflected in the different cM and SNP values.

So, who is triangulated based on just this one green cluster?  Barbara, Cheryl, Don and Arthur are triangulated to a common ancestor.  We know that common ancestor is either the common ancestor of Cheryl, Don and Barbara – Hiram Ferverda and Evaline Miller – or upstream of that couple.

Tiffany is triangulated to both Cheryl and Don, but since Cheryl and Don are siblings, that’s irrelevant at this point – meaning we can’t tell if that match is IBS by chance or real because there is no additional match – at least not in this cluster.

In total, there are 19 green clusters (triangulated to at least 4 people) and 12 yellow clusters (triangulated to at least 3 people.)

In other words, the DNA that came from Hiram Ferverda and Evaline Miller is present in these matching people as well.  The million dollar question, is, of course, which upstream ancestor did it come from?  We genealogists are never satisfied, are we?  Every answer just leads to more questions.

Before we begin looking at the DNA results and discussing what they mean, I want to share with you the family tree of Hiram Ferverda and Evaline Miller, because the DNA of the people who match Don, Cheryl and Barbara had to come from these people as well.  This chart shows 7 generations back from Barbara, Cheryl and Don.  The common ancestors of the people with whom they triangulate are likely to be within this timeframe.

two cousins fan chart

The colorized ancestors above are the ancestors who contributed the X chromosome to both John Ferverda, Barbara’s father and Roscoe Ferverda, Cheryl and Don’s father.

In my working example, below, I’m utilizing the matches on chromosome 14 because chromosome 14 includes examples of a couple of interesting features.

Two cousins chr 14

Let’s look at the first green grouping.  All three cousins match to SB and then Barbara matches also to Constance and William, our Lentz cousin on part of that overlapping segment as well.  This suggests that this grouping might come from the Lentz side of the Miller tree, although we’ll see something else in a minute that might give us pause to reflect.  So just hold that thought.  Regardless, it does tell us that these individuals do share a common ancestor and it’s on the Miller side, not the Ferverda side.

The second green grouping is larger and includes larger segments as well, which are more reliably used, although the smaller green cluster clearly meets and exceeds the triangulation requirement of 3 matching individuals on the same segment.

This larger green cluster is actually quite interesting, because there are a total of 4 individuals, Ellen, Arthur, Eric and Tiffany who are all triangulated on this same segment with Don, Cheryl and Barbara.  So, not only are they triangulated to Don, Cheryl and Barbara, but also to each other.  These 7 people all share a common ancestor.

The yellow grouping shows an area where Eric matches Barbara and Don plus Arthur as well, but not Cheryl.  We don’t know anything about Arthur or Eric’s genealogy, so we don’t know if this is Miller or Ferverda DNA, at least not yet.  We’ll learn more about Arthur and Eric in a minute, even without their genealogy!

There are a couple of other areas on other chromosomes that are of interest too.

On this cluster on chromosome 12, we find a known Miller cousin, Rex, 2nd cousin to Barbara, Cheryl and Don.  Because Rex also descends from the parents of Evaline Miller, we know that this segment shared with Rex has to be Miller DNA, not Ferverda DNA.

Two cousins chr 12

On this segment of chromosome 3, below, we see that Barbara, Cheryl and Don match Herbert, another known Miller cousin, plus Dee and Constance in much smaller amounts on the same segment.  This tells us that this segment is descended from our common ancestor with Herbert.

Two cousins chr 3

Barbara, Don and Cheryl’s common ancestor with Herbert is Daniel Miller and Elizabeth Ulrich (Ullery), which makes them third cousins once removed – except – Herbert got a second dose of Miller DNA because Daniel Miller’s son, Isaac, married his first cousin who was also a Miller and shared grandparents with him.  So Herbert, genetically, is closer than he would appear since he received the double dose of Miller DNA three generations upstream.

Gotta love these close knit families.  The Millers were Brethren.  These double doses of family DNA often carry forward by matching downstream when they might otherwise not be expected do so.  That’s the upside of these endogamous groups.  Now, here’s the downside.

Two cousins chr 7

See the segments with the words problem written to the right?  Do you recognize what the problem is?  You’ll notice that in the matching group we have BOTH cousin Herbert who is a Miller (and not a Lentz) and cousin William who is a Lentz (and not a Miller.)

This is a very common situation in endogamous communities.

To make matters worse, we are dealing with very small segments here, where we often see confusion.  However, let’s look at the possibilities.

We do have triangulation, so one of three things has happened here.

First, the Brethren are an endogamous population that intermarried nearly exclusively within their faith.  The Lentz and Miller families were both Brethren.

Here are our possibilities.

  1. Our Lentz cousin has some Miller in one of his lines. This is entirely possible since he has a “short” pedigree chart and his families are living in the same Brethren communities as the other Lentz and Miller families.
  2. Our Miller cousin has some Lentz in one of his lines. That is less likely, because his genealogy is pretty well fleshed out, although certainly possible because, once again, the families were living within close proximity and attending the same churches, etc.
  3. This segment is truly a population based segment and will be found in people descending from that same base population. If this is the case, we still received it from one of our ancestors who came from that population, but since the Lentz and Miller lines may have both carried this same segment, we can’t tell who it came from. In other words, their common ancestor is further back in time than the Lentz and Miller families found in the US.

This segment cannot be IBS by chance because it does triangulate with the three cousins, Barbara, Don and Cheryl.  The definition of IBS by chance shows us that chance segments would not phase (or match with) with a parent.  If Don, Cheryl and Barbara all three carry this matching segment, it’s because their fathers both received it from their grandparents who were the common ancestor of Don, Cheryl and Barbara.

Neither Cheryl, Don nor Barbara can phase directly to their parents, who are deceased, so in this case, matching against first cousins is the best substitute we have.  We know that common DNA between the first cousins had to come from their father’s, who were brothers.  This in essence virtually phases Barbara, Don and Cheryl to their father’s on these matching segments.  Not ideal, by any means, but even partial parental phasing is better than no phasing at all.

A third match, Dean, shows Miller in his family tree, but I could not connect his Miller line to the Johann Michael Miller ancestral line, from which our Miller line descends – so Dean is not a known cousin.  Sometimes a common surname, even if found in the same geographic location, is not proof that the DNA connection is through that line.  It’s easy to make that assumption, but it’s an assumption that is just waiting to bite you.  Don’t do it!

Because of our known, proven DNA and genealogy matches to Herbert, we can attribute all of the segments where Herbert triangulates with either Barbara and Cheryl or Barbara and Don as Miller for all people involved.  This means that this common DNA descends either from Daniel Miller and Elizabeth Ulrich or Daniel’s father Philip Jacob Miller and Magdalene, surname unknown.

Why have I listed two couples?  Because, remember, Herbert has a double dose of Miller DNA from cousins and we don’t know which segment Barbara inherited, one from Daniel/Elizabeth or one from Philip Jacob/Magdalene (or some of each.)  If the segment is from Daniel/Elizabeth, it could have come from either the Ulrich or Miller side.  If it came from Daniel, then it also came from his father and mother, Philip Jacob/Magdalena and could either be Miller or Magdalena’s unknown line.

Herbert triangulate

Because of our known, proven DNA and genealogy matches to Rex, we can attribute all of the segments where Rex triangulates with either Barbara and Cheryl or Barbara and Don as Miller for all people involved.  Their common ancestor is John David Miller and Margaret Lentz, so their shared DNA could be either Lentz or Miller and is likely some of each.

Rex triangulate

For segments where there is no triangulation, but Barbara matches either Herbert or Rex, I still note that segment as Miller on my spreadsheet, since they are proven cousins, but I just omit the triangulation note.

For Barbara, that’s a total of 51 segments of her DNA that we can now assign to a Miller ancestral couple.

Furthermore, every segment that Barbara matches with either Cheryl or Don is now confirmed to be from her father’s side of the family, not her mother’s.  While we don’t have Barbara’s parents available for testing, this is a pseudo way to phase your results to determine matches from one parents’ side of the family.  For Barbara, that’s a total of 91 segments, some of them quite large.  For example, roughly half of chromosome 13 matched with Don.

Just as a matter of interest, within those 91 segments that Barbara matches with either Don or Cheryl, a total of only 7 segments matched exactly between all 3 individuals in terms of start and end location, cMs and SNPs.  While you might expect a number of small segments to match exactly, these weren’t all small.  In fact, most weren’t small and some were quite large.

Exactly matching DNA segments between Barbara and Cheryl and Barbara and Don.

Chromosome Matching cM Matching SNPs
1 8.65 1189
1 7.01 1150
8 27.79 7279
10 20.78 5141
12 27.68 6046
14 2.11 700
14 49.47 9032

This means that these segments were not divided at all in a total of 5 DNA transmission events.

  • Hiram to John
  • Hiram to Roscoe
  • John to Barbara
  • Roscoe to Cheryl
  • Roscoe to Don

Additionally, I carry two of these exact segments as well, so those two segments survived 6 transmission events.

Clearly these segments are what we would term “sticky” because they certainly are not following the statistical average of dividing the DNA in half (by 50%) in each transmission event.

There is one more thing we can tell from matching.

Both Barbara and Cheryl match with SB on the X chromosome on the same segments.

Two cousins X

This is particularly interesting because of the special inheritance path of the X chromosome.  We know that SB must be related on Evaline Miller’s side of the family, because John and Roscoe Ferverda did not receive an X chromosome from their father.  So Barbara, Cheryl and Don have to have received it from Evaline.  Unfortunately, SB listed no genealogy on Family Tree DNA, but based on the X chromosome inheritance path, I can tell you that SB is either descended from John David Miller and Margaret Lentz, or from the Schaeffer, Lentz or Moselman lines colored pink or blue, below.

Two cousins X fan

At this point, I made a chart of how the matches grouped with each other on each of the green clusters.

Just one cousin chart

I intended to create a nice chart in Excel or Word, but with all of the various colors of ink involved, I didn’t think I could find enough color differentiation so we’ll just have to suffer with my hand-made chart.  There are subtle color differences here – a different color or marker type for each of the 19 green clusters.

What I did was to look at each of the green DNA spreadsheet groupings and create a colorized chart, by group, for each grouping.  So everyone in the first cluster had their X in the boxes of who they matches in the same color, say blue pen.  The second group, orange marker, and so forth.  That way I can see who was orange or yellow or blue and if those groups tend to cluster together.

Remember Arthur and Eric from above, whose genealogy we knew nothing about.  You can see, for example, that Arthur matches in various groups with lots of people, and most often, Tiffany.  Arthur and Eric also match in multiple groups that include each other and Rex, a known Miller descendant, so we can attribute both Arthur and Eric’s DNA matches to the Miller side of the tree.  Keep in mind, all of these people also match with Barbara, Cheryl and Don.

Tiffany clusters with Arthur and Sarah and Eric in multiple groups and with Constance, David, Ellen, Leland and Rex in at least one other cluster.  So another Miller side person.

On chromosome 14, Eric, Ellen, Arthur and Tiffany were all triangulated on the same segment with Don, Cheryl and Barbara, so we know those 7 individuals unquestionably share a common ancestor.

Let’s look at SB again, our X match.  Since SB’s X connection can’t come from the Miller side, given the X inheritance path, and SB also matches with our Lentz cousin, it’s likely that SB is related through the Lentz lines.

Normally, when doing this matching relationship chart, you tend to see two distinct groupings, a mother’s side and a father’s side.  In other words, there will be some groups that absolutely don’t overlap with the others.  That’s not the case here.

So, by now you might be wondering what happened to the Ferverda side of the family?  I was secretly hoping to find a closet Ferverda relative in this exercise, and I thought we might have, actually.  Notice that Harold has no clustering at all, but he clearly matches Barbara, Cheryl and Don – but doesn’t cluster with any other Miller or Lentz cousins.  Therefore, he could be from the Ferverda side of the family, but since he provided no genealogy information or surnames at Family Tree DNA, I can’t easily tell.

However, I am not entirely without recourse.  I checked Harold “in common with” Barbara and discovered that he matches both Rex, our Miller cousin and William, our Lentz cousin, so even though Harold did not triangulate with William and/or Rex on any segments with both Barbara and/or Cheryl/Don, those Miller/Lentz matches certainly suggest descent from this line.  I’ll be sending him an e-mail!

So, there are no Ferverda cousins represented in these matches.

I decided to check one more thing, now that I know that all of these matches are on the Miller side and that we have 3 known, proven genealogical cousins, Rex, Herbert and William.  I wanted to see how many of our individuals who match Barbara, Cheryl and Don also match one of the known cousins.  I selected Barbara as the base match kit to use, since we know they all matched Barbara, Cheryl and Don, and then I ran “in common with” for each one of them with Barbara, with the following results.  A few did match one of the Miller or Lentz cousins, but fewer than I expected.miller matches chart

*However, we had a surprise.  Dean matched another Miller male individual whose line is proven to descend through two children of Philip Jacob Miller and Magdalena, surname unknown.  Another first cousin marriage.  Another cousin discovered!

Furthermore, I noticed yet another individual, Doug, in Barbara’s match list and in common with 6 of the matches as well.  Looking at Doug’s pedigree chart, not only is he a Miller descendant, he also descends from two of the Miller wives lines too.  Another cousin confirmed!

But why no Ferverda matches?

Recent immigrants.

The Ferverda side of the family immediately jumps the pond to Holland, with Hiram himself being an immigrant as a young teen in the 1860s.  There are few Ferverda (Fervida, Ferwerda) descendants here in the US to test, and many are Brethren or Mennonite.  Few people in the Netherlands have participated in DNA testing.

The converse of that, Evaline Miller’s lines have all been in the US since the early/mid-1700s, so there are lots of descendants.  Oh, the difference about a hundred years and 5 or 6 generations makes in the number of descendants who might be available to test.  This situation, unfortunately, created a very lopsided chart without the division I’m used to seeing.  On the other hand, thank goodness Evaline’s line and Hiram’s line are very distinct!

At this point, if you’re doing this “one cousin” exercise, you’ll need to do a few things.

1.  Check each of the matching individuals to see if they have uploaded or created a pedigree chart at Family Tree DNA. If they do, their pedigree icon will be green, shown below. If so, click on the icon and search for every surname (and variant) associated with your known common lines with your cousin.

2.  Check to see if these people entered a list of surnames, even if they don’t have a pedigree chart. The surnames are listed in the furthest right column. If you have entered your surnames, any that match yours will be bolded. Beware of variant spellings.

two cousins pedigree and surnames

You can see above that I am the only one of the matches shown with a pedigree chart icon, shown in green, and the common surnames are bolded at right.

3.  If your matches don’t have a pedigree chart, write to them and tell them you have a common ancestor and give them a list of your ancestors in your direct line. Please, PLEASE include the name on the kit that you match. Many people manage multiple kits and will ignore requests with only partial information.

4.  If you have additional cousins to test, do so. I’m sure you can see how valuable additional cousins DNA would be.

5.  Be sure to check your matches by “ancestral surname” to be sure that you haven’t missed any cousins who have already tested. The ancestral surname search box can be seen above the “known relationship” heading in the graphic above.

6.  If you haven’t done so, enter your surnames under the “Manage Personal Information” tab under “My Account” at Family Tree DNA. Then click on the genealogy tab, then Surnames.

Two cousins genealogy settings

7.  From your main personal page, of course, you can upload your Gedcom file by clicking on “My Family Tree.”

8.  Run “in common with” for each of the common matches of your two cousins and look for common matching names between them.  Those matching “in common with” names serve as a hint as to shared ancestry.  Your answer may be hiding in your cousins’ trees!

Utilize all of these tools to help your search.

Summary

Not bad for thinking we couldn’t do anything with our DNA matches because we had “just one cousin” to work with, even though I cheated and used siblings.

What, exactly, did we manage to do?

  • I attributed 91 segments of Barbara’s DNA to her father’s side of the tree.
  • I filled in 51 segments of Barbara’s DNA to ancestral couples.
  • I found 5 confirmed genealogy/DNA cousins.
  • I found 16 people whose genealogy is unknown, but who triangulate with Barbara, Cheryl and Don.  We know for sure which side of the tree these people match on – all Millers.
  • I can tell the X match which lines they descend from, even if they don’t know.
  • I can do one more very cool thing.  Utilizing the Lazarus utility at GedMatch, I can now recreate at least a partial autosomal DNA file for both John and Roscoe Ferverda, the fathers of our testers.  Join me in a couple days and we’ll see how that works!

This same process works between any two people who know how they are related and their common ancestor.  It’s a great way to find cousins you didn’t know you had, or you didn’t know have DNA tested, and how they are related to you and each other.

Some people get very discouraged when even thinking about working with endogamous populations, or cousin marriages.  One of the reasons I used this particular example is that I wanted to illustrate that while these situations are challenging from time to time, they are far from hopeless – so don’t let that deter you.

In fact, of the 5 confirmed cousins discovered during this process, some in unexpected ways, at least 3 and possibly 4 are through multiple lines.  Some of these matches are probably thanks to endogamy.

Happy hunting!

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Chromosome Browser War

There has been a lot of discussion lately, and I mean REALLY a lot, about chromosome browsers, the need or lack thereof, why, and what the information really means.

For the old timers in the field, we know the story, the reasons, and the backstory, but a lot of people don’t.  Not only are they only getting pieces of the puzzle, they’re confused about why there even is a puzzle.  I’ve been receiving very basic questions about this topic, so I thought I’d write an article about chromosome browsers, what they do for us, why we need them, how we use them and the three vendors, 23andMe, Ancestry and Family Tree DNA, who offer autosomal DNA products that provide a participant matching data base.

The Autosomal Goal

Autosomal DNA, which tests the part of your DNA that recombines between parents every generation, is utilized in genetic genealogy to do a couple of things.

  1. To confirm your connection to a specific ancestor through matches to other descendants.
  2. To break down genealogy brick walls.
  3. Determine ethnicity percentages which is not the topic of this article.

The same methodology is used for items 1 and 2.

In essence, to confirm that you share a common ancestor with someone, you need to either:

  1. Be a close relative – meaning you tested your mother and/or father and you match as expected. Or, you tested another known relative, like a first cousin, for example, and you also match as expected. These known relationships and matches become important in confirming or eliminating other matches and in mapping your own chromosomes to specific ancestors.
  2. A triangulated match to at least two others who share the same distant ancestor. This happens when you match other people whose tree indicates that you share a common ancestor, but they are not previously known to you as family.

Triangulation is the only way you can prove that you do indeed share a common ancestor with someone not previously identified as family.

In essence, triangulation is the process by which you match people who match you genetically with common ancestors through their pedigree charts.  I wrote about the process in this article “Triangulation for Autosomal DNA.”

To prove that you share a common ancestor with another individual, the DNA of  three proven descendants of that common ancestor must match at the same location.  I should add a little * to this and the small print would say, “ on relatively large segments.”  That little * is rather controversial, and we’ll talk about that in a little bit.  This leads us to the next step, which is if you’re a fourth person, and you match all three of those other people on that same segment, then you too share that common ancestor.  This is the process by which adoptees and those who are searching for the identity of a parent work through their matches to work forward in time from common ancestors to, hopefully, identify candidates for individuals who could be their parents.

Why do we need to do this?  Isn’t just matching our DNA and seeing a common ancestor in a pedigree chart with one person enough?  No, it isn’t.  I recently wrote about a situation where I had a match with someone and discovered that even though we didn’t know it, and still don’t know exactly how, we unquestionably share two different ancestral lines.

When you look at someone’s pedigree chart, you may see immediately that you share more than one ancestral line.  Your shared DNA could come from either line, both lines, or neither line – meaning from an unidentified common ancestor.  In genealogy parlance, those are known as brick walls!

Blaine Bettinger wrote about this scenario in his now classic article, “Everyone Has Two Family Trees – A Genealogical Tree and a Genetic Tree.”

Proving a Match

The only way to prove that you actually do share a genealogy relative with someone that is not a known family member is to triangulate.  This means searching other matches with the same ancestral surname, preferably finding someone with the same proven ancestral tree, and confirming that the three of you not only share matching DNA, but all three share the same matching DNA segments.  This means that you share the same ancestor.

Triangulation itself is a two-step process followed by a third step of mapping your own DNA so that you know where various segments came from.  The first two triangulation steps are discovering that you match other people on a common segment(s) and then determining if the matches also match each other on those same segments.

Both Family Tree DNA and 23andMe, as vendors have provided ways to do most of this.  www.gedmatch.com and www.dnagedcom.com both augment the vendor offerings.  Ancestry provides no tools of this type – which is, of course, what has precipitated the chromosome browser war.

Let’s look at how the vendors products work in actual practice.

Family Tree DNA

1. Chromosome browser – do they match you?

Family Tree DNA makes it easy to see who you match in common with someone else in their matching tool, by utilizing the ICW crossed X icon.

chromosome browser war13

In the above example, I am seeing who I match in common with my mother.  Sure enough, our three known cousins are the closest matches, shown below.

chromosome browser war14

You can then push up to 5 individuals through to the chromosome browser to see where they match the participant.

The following chromosome browser is an example of a 4 person match showing up on the Family Tree DNA chromosome browser.

This example shows known cousins matching.  But this is exactly the same scenario you’re looking for when you are matching previously unknown cousins – the exact same technique.

In this example, I am the participant, so these matches are matches to me and my chromosome is the background chromosome displayed.  I have switched from my mother’s side to known cousins on my father’s side.

chromosome browser war1

The chromosome browser shows that these three cousins all match the person whose chromosomes are being shown (me, in this case), but it doesn’t tell you if they also match each other.  With known cousins, it’s very unlikely (in my case) that someone would match me from my mother’s side, and someone from my father’s side, but when you’re working with unknown cousins, it’s certainly possible.  If your parents are from the same core population, like Germans or an endogamous population, you may well have people who match you on both sides of your family.  Simply put, you can’t assume they don’t.

It’s also possible that the match is a genuine genealogical match, but you don’t happen to match on the exact same segments, so the ancestor can’t yet be confirmed until more cousins sharing that same ancestral line are found who do match, and it’s possible that some segments could be IBS, identical by state, meaning matches by chance, especially small segments, below the match threshold.

2. Matrix – do they match each other?

Family Tree DNA also provides a tool called the Matrix where you can see if all of the people who match on the same segment, also match each other at some place on their DNA.

chromosome browser war2

The Matrix tool measures the same level of DNA as the default chromosome browser, so in the situation I’m using for an example, there is no issue.  However, if you drop the threshold of the match level, you may well, and in this case, you will, find matches well below the match threshold.  They are shown as matches because they have at least one segment above the match threshold.  If you don’t have at least one segment above the threshold, you’ll never see these smaller matches.  Just to show you what I mean, this is the same four people, above, with the threshold lowered to 1cM.  All those little confetti pieces of color are smaller matches.

chromosome browser war3

At Family Tree DNA, the match threshold is about 7cM.  Each of the vendors has a different threshold and a different way of calculating that threshold.

The only reason I mention this is because if you DON’T match with someone on the matrix, but you also show matches at smaller segments, understand that matrix is not reporting on those, so matrix matches are not negative proof, only positive indications – when you do match, both on the chromosome browser and utilizing the matrix tool.

What you do know at this point is that these individuals all match you on the same segments, and that they match each other someplace on their chromosomes, but what you don’t know is if they match each other on the same locations where they match you.

If you are lucky and your matches are cousins or experienced genetic genealogists and are willing to take a look at their accounts, they can tell you if they match the other people on the same segments where they match you – but that’s the only way to know unless they are willing to download their raw data file to GedMatch.  At GedMatch, you can adjust the match thresholds to any level you wish and you can compare one-to-one kits to see where any two kits who have provided you with their kit number match each other.

3. Downloading data – mapping your chromosome.

The “download to Excel” function at Family Tree DNA, located just above the chromosome browser graphic, on the left, provides you with the matching data of the individuals shown on the chromosome browser with their actual segment data shown. (The download button on the right downloads all of your matches, not just the ones shown in the browser comparison.)

The spreadsheet below shows the downloaded data for these four individuals.  You can see on chromosome 15 (yellow) there are three distinct segments that match (pink, yellow and blue,) which is exactly what is reflected on the graphic browser as well.

chromosome browser war4

On the spreadsheet below, I’ve highlighted, in red, the segments which appeared on the original chromosome browser – so these are only the matches at or over the match threshold.

chromosome browser war5

As you can see, there are 13 in total.

Smaller Segments

Up to this point, the process I’ve shared is widely accepted as the gold standard.

In the genetic genealogy community, there are very divergent opinions on how to treat segments below the match threshold, or below even 10cM.  Some people “throw them away,” in essence, disregard them entirely.  Before we look at a real life example, let’s talk about the challenges with small segments.

When smaller segments match, along with larger segments, I don’t delete them, throw them away, or disregard them.  I believe that they are tools and each one carries a message for us.  Those messages can be one of four things.

  1. This is a valid IBD, meaning identical by descent, match where the segment has been passed from one specific ancestor to all of the people who match and can be utilized as such.
  2. This is an IBS match, meaning identical by state, and is called that because we can’t yet identify the common ancestor, but there is one. So this is actually IBD but we can’t yet identify it as such. With more matches, we may well be able to identify it as IBD, but if we throw it away, we never get that chance. As larger data bases and more sophisticated software become available, these matches will fall into place.
  3. This is an IBS match that is a false match, meaning the DNA segments that we receive from our father and mother just happen to align in a way that matches another person. Generally these are relatively easy to determine because the people you match won’t match each other. You also won’t tend to match other people with the same ancestral line, so they will tend to look like lone outliers on your match spreadsheets, but not always.
  4. This is an IBS match that is population based. These are much more difficult to determine, because this is a segment that is found widely in a population. The key to determining these pileup areas, as discussed in the Ancestry article about their new phasing technique, if that you will find this same segment matching different proven lineages. This is the reason that Ancestry has implemented phasing – to identify and remove these match regions from your matches. Ancestry provided a graphic of my pileup areas, although they did not identify for me where on my chromosomes these pileup regions occurred. I do have some idea however, because I’ve found a couple of areas where I have matches from my mother’s side of the family from different ancestors – so these areas must be IBS on a population level. That does not, however, make them completely irrelevant.

genome pileups

The challenge, and problem, is where to make the cutoff when you’re eliminating match areas based on phased data.  For example, I lost all of my Acadian matches at Ancestry.  Of course, you would expect an endogamous population to share lots of the same DNA – and there are a huge number of Acadian descendants today – they are in fact a “population,” but those matches are (were) still useful to me.

I utilize Acadian matches from Family Tree DNA and 23andMe to label that part of my chromosome “Acadian” even if I can’t track it to a specific Acadian ancestor, yet.  I do know from which of my mother’s ancestors it originated, her great-grandfather, who is her Acadian ancestor.  Knowing that much is useful as well.

The same challenge exists for other endogamous groups – people with Jewish, Mennonite/Brethren/Amish, Native American and African American heritage searching for their mixed race roots arising from slavery.  In fact, I’d go so far as to say that this problem exists for anyone looking for ancestors beyond the 5th or 6th generation, because segments inherited from those ancestors, if there are any, will probably be small and fall below the generally accepted match thresholds.  The only way you will be able to find them, today, is the unlikely event that there is one larger segments, and it leads you on a search, like the case with Sarah Hickerson.

I want to be very clear – if you’re looking for only “sure thing” segments – then the larger the matching segment, the better the odds that it’s a sure thing, a positive, indisputable, noncontroversial match.  However, if you’re looking for ancestors in the distant past, in the 5th or 6th generation or further, you’re not likely to find sure thing matches and you’ll have to work with smaller segments. It’s certainly preferable and easier to work with large matches, but it’s not always possible.

In the Ralph and Coop paper, The Geography of Recent Genetic Ancestry Across Europe, they indicated that people who matched on segments of 10cM or larger were more likely to have a common ancestor with in the past 500 years.  Blocks of 4cM or larger were estimated to be from populations from 500-1500 years ago.  However, we also know that there are indeed sticky segments that get passed intact from generation to generation, and also that some segments don’t get divided in a generation, they simply disappear and aren’t passed on at all.  I wrote about this in my article titled, Generational Inheritance.

Another paper by Durand et al, Reducing pervasive false positive identical-by-descent segments detected by large-scale pedigree analysis, showed that 67% of the 2-4cM segments were false positives.  Conversely, that also means that 33% of the 2-4cM segments were legitimate IBD segments.

Part of the disagreement within the genetic genealogy community is based on a difference in goals.  People who are looking for the parents of adoptees are looking first and primarily as “sure thing” matches and the bigger the match segment, of course, the better because that means the people are related more closely in time.  For them, smaller segments really are useless.  However, for people who know their recent genealogy and are looking for those brick wall ancestors, several generations back in time, their only hope is utilizing those smaller segments.  This not black and white but shades of grey.  One size does not fit all.  Nor is what we know today the end of the line.  We learn every single day and many of our learning experiences are by working through our own unique genealogical situations – and sharing our discoveries.

On this next spreadsheet, you can see the smaller segments surrounding the larger segments – in other words, in the same match cluster – highlighted in green.  These are the segments that would be discarded as invalid if you were drawing the line at the match threshold.  Some people draw it even higher, at 10 cM.  I’m not being critical of their methodology or saying they are wrong.  It may well work best for them, but discarding small segments is not the only approach and other approaches do work, depending on the goals of the researcher.  I want my 33% IBD segments, thank you very much.

All of the segments highlighted in purple match between at least three cousins.  By checking the other cousins accounts, I can validate that they do all match each other as well, even though I can’t tell this through the Family Tree DNA matrix below the matching threshold.  So, I’ve proven these are valid.  We all received them from our common ancestor.

What about the white rows?  Are those valid matches, from a common ancestor?  We don’t have enough information to make that determination today.

chromosome browser war6

Downloading my data, and confirming segments to this common ancestor allows me to map my own chromosomes.  Now, I know that if someone matches me and any of these three cousins on chromosome 15, for example, between 33,335,760 and 58,455,135 – they are, whether they know it or not, descended from our common ancestral line.

In my opinion, I would think it a shame to discount or throw away all of these matches below 7cM, because you would be discounting 39 of your 52 total matches, or 75% of them.  I would be more conservative in assigning my segments with only one cousin match to any ancestor, but I would certainly note the match and hope that if I added other cousins, that segment would be eventually proven as IBD.

I used positively known cousins in this example because there is no disputing the validity of these matches.  They were known as cousins long before DNA testing.

Breaking Down Brick Walls

This is the same technique utilized to break down brick walls – and the more cousins you have tested, so that you can identify the maximum number of chromosome pieces of a particular ancestor – the better.

I used this same technique to identify Sarah Hickerson in my Thanksgiving Day article, utilizing these same cousins, plus several more.

Hey, just for fun, want to see what chromosome 15 looks like in this much larger sample???

In this case, we were trying to break down a brick wall.  We needed to determine if Sarah Hickerson was the mother of Elijah Vannoy.  All of the individuals in the left “Name” column are proven Vannoy cousins from Elijah, or in one case, William, from another child of Sarah Hickerson.  The individuals in the right “Match” column are everyone in the cousin match group plus the people in green who are Hickerson/Higginson descendants.  William, in green, is proven to descend from Sarah Hickerson and her husband, Daniel Vannoy.

chromosome browser war7

The first part of chromosome 15 doesn’t overlap with the rest.  Buster, David and I share another ancestral line as well, so the match in the non-red section of chromosome 15 may well be from that ancestral line.  It becomes an obvious possibility, because none of the people who share the Vannoy/Hickerson/Higginson DNA are in that small match group.

All of the red colored cells do overlap with at least one other individual in that group and together they form a cluster.  The yellow highlighted cells are the ones over the match threshold.  The 6 Hickerson/Higginson descendants are scattered throughout this match group.

And yes, for those who are going to ask, there are many more Vannoy/Hickerson triangulated groups.  This is just one of over 60 matching groups in total, some with matches well above the match threshold. But back to the chromosome browser wars!

23andMe

This example from 23andMe shows why it’s so very important to verify that your matches also match each other.

chromosome browser war8

Blue and purple match segments are to two of the same cousins that I used in the comparison at Family Tree DNA, who are from my father’s side.  Green is my first cousin from my mother’s side.   Note that on chromosome 11, they both match me on a common segment.  I know by working with them that they don’t match each other on that segment, so while they are both related to me, on chromosome 11, it’s not through the same ancestor.  One is from my father’s side and one is from my mother’s side.  If I hadn’t already known that, determining if they matched each other would be the acid test and would separate them into 2 groups.

23andMe provides you with a tool to see who your matches match that you match too.  That’s a tongue twister.

In essence, you can select any individual, meaning you or anyone that you match, on the left hand side of this tool, and compare them to any 5 other people that you match.  In my case above, I compared myself to my cousins, but if I want to know if my cousin on my mother’s side matches my two cousins on my father’s side, I simply select her name on the left and theirs on the right by using the drop down arrows.

chromosome browser war9

I would show you the results, but it’s in essence a blank chromosome browser screen, because she doesn’t match either of them, anyplace, which tells me, if I didn’t already know, that these two matches are from different sides of my family.

However, in other situations, where I match my cousin Daryl, for example, as well as several other people on the same segment, I want to know how many of these people Daryl matches as well.  I can enter Daryl’s name, with my name and their names in the group of 5, and compare.  23andMe facilitates the viewing or download of the results in a matrix as well, along with the segment data.  You can also download your entire list of matches by requesting aggregated data through the link at the bottom of the screen above or the bottom of the chromosome display.

I find it cumbersome to enter each matches name in the search tool and then enter all of the other matches names as well.  By utilizing the tools at www.dnagedcom.com, you can determine who your matches match as well, in common with you, in one spreadsheet.  Here’s an example.  Daryl in the chart below is my match, and this tool shows you who else she matches that I match as well, and the matching segments.  This allows me to correlate my match with Gwen for example, to Daryl’s match to Gwen to see if they are on the same segments.

chromosome browser war10

As you can see, Daryl and I both match Gwen on a common segment.  On my own chromosome mapping spreadsheet, I match several other people as well at that location, at other vendors, but so far, we haven’t been able to find any common genealogy.

Ancestry.com

At Ancestry.com, I have exactly the opposite problem.  I have lots of people I DNA match, and some with common genealogy, but no tools to prove the DNA match is to the common ancestor.

Hence, this is the crux of the chromosome browser wars.  I’ve just showed you how and why we use chromosome browsers and tools to show if our matches match each other in addition to us and on which segments.  I’ve also illustrated why.  Neither 23andMe nor Family Tree DNA provides perfect tools, which is why we utilize both GedMatch and DNAGedcom, but they do provide tools.  Ancestry provides no tools of this type.

At Ancestry, you have two kinds of genetic matches – ones without tree matches and ones with tree matches.  Pedigree matching is a service that Ancestry provides that the other vendors don’t.  Unfortunately, it also leads people to believe that because they match these people genetically and share a tree, that the tree shown is THE genetic match and it’s to the ancestor shown in the tree.  In fact, if the tree is wrong, either your tree or their tree, and you match them genetically, you will show up as a pedigree match as well.  Even if both pedigrees are right, that still doesn’t mean that your genetic match is through that ancestor.

How many bad trees are at Ancestry percentagewise?  I don’t know, but it’s a constant complaint and there is absolutely nothing Ancestry can do about it.  All they can do is utilize what they have, which is what their customers provide.  And I’m glad they do.  It does make the process of working through your matches much easier. It’s a starting point.  DNA matches with trees that also match your pedigree are shown with Ancestry’s infamous shakey leaf.

In fact, in my Sarah Hickerson article, it was a shakey leaf match that initially clued me that there was something afoot – maybe. I had to shift to another platform (Family Tree DNA) to prove the match however, where I had tools and lots of known cousins.

At Ancestry, I now have about 3000 matches in total, and of those, I have 33 shakey leaves – or people with whom I also share an ancestor in our pedigree charts.  A few of those are the same old known cousins, just as genealogy crazy as me, and they’ve tested at all 3 companies.

The fly in the ointment, right off the bat, is that I noticed in several of these matches that I ALSO share another ancestral line.

Now, the great news is that Ancestry shows you your surnames in common, and you can click on the surname and see the common individuals in both trees.

The bad news is that you have to notice and click to see that information, found in the lower left hand corner of this screen.

chromosome browser war11

In this case, Cook is an entirely different line, not connected to the McKee line shown.

However, in this next case, we have the same individual entered in our software, but differently.  It wasn’t close enough to connect as an ancestor, but close enough to note.  It turns out that Sarah Cook is the mother of Fairwick Claxton, but her middle name was not Helloms, nor was her maiden name, although that is a long-standing misconception that was proven incorrect with her husband’s War of 1812 documents many years ago. Unfortunately, this misinformation is very widespread in trees on the internet.

chromosome browser war12

Out of curiosity, and now I’m sorry I did this because it’s very disheartening – I looked to see what James Lee Claxton/Clarkson’s wife’s name was shown to be on the first page of Ancestry’s advanced search matches.

Despite extensive genealogical and DNA research, we don’t know who James Lee Claxton/Clarkson’s parents are, although we’ve disproven several possibilities, including the most popular candidate pre-DNA testing.  However, James’ wife was positively Sarah Cook, as given by her, along with her father’s name, and by witnesses to their marriage provided when she applied for a War of 1812 pension and bounty land.  I have the papers from the National Archives.

James Lee Claxton’s wife, Sara Cook is identified as follows in the first 50 Ancestry search entries.

Sarah Cook – 4

Incorrect entries:

  • Sarah Cook but with James’ parents listed – 3
  • Sarah Helloms Cook – 2, one with James’ parents
  • Sarah Hillhorns – 15
  • Sarah Cook Hitson – 13, some with various parents for James
  • No wife, but various parents listed for James – 12
  • No wife, no parents – 1

I’d much rather see no wife and no parents than incorrect information.

Judy Russell has expressed her concern about the effects of incorrect trees and DNA as well and we shared this concern with Ancestry during our meeting.

Ancestry themselves in their paper titled “Identifying groups of descendants using pedigrees and genetically inferred relationships in a large database” says, “”As with all analyses relating to DNA Circles™, tree quality is also an important caveat and limitation.”  So Ancestry is aware, but they are trying to leverage and utilize one of their biggest assets, their trees.

This brings us to DNA Circles.  I reviewed Ancestry’s new product release extensively in my Ancestry’s Better Mousetrap article.  To recap briefly, Ancestry gathers your DNA matches together, and then looks for common ancestors in trees that are public using an intelligent ranking algorithm that takes into account:

  1. The confidence that the match is due to recent genealogical history (versus a match due to older genealogical history or a false match entirely).
  2. The confidence that the identified common recent ancestor represents the same person in both online pedigrees.
  3. The confidence that the individuals have a match due to the shared ancestor in question as opposed to from another ancestor or from more distant genealogical history.

The key here is that Ancestry is looking for what they term “recent genealogical history.”  In their paper they define this as 10 generations, but the beta version of DNA Circles only looks back 7 generations today.  This was also reflected in their phasing paper, “Discovering IBD matches across a large, growing database.”

However, the unfortunate effect has been in many cases to eliminate matches, especially from endogamous groups.  By way of example, I lost my Acadian matches in the Ancestry new product release.  They would have been more than 7 generations back, and because they were endogamous, they may have “looked like” IBS segments, if IBS is defined at Ancestry as more than 7 or 10 generations back.  Hopefully Ancestry will tweek this algorithm in future releases.

Ancestry, according to their paper, “Identifying groups of descendants using pedigrees and genetically inferred relationships in a large database,” then clusters these remaining matching individuals together in Circles based on their pedigree charts.  You will match some of these people genetically, and some of them will not match you but will match each other.  Again, according to the paper, “these confidence levels are calculated by the direct-line pedigree size, the number of shared ancestral couples and the generational depth of the shared MRCA couple.”

Ancestry notes that, “using the concordance of two independent pieces of information, meaning pedigree relationships and patterns of match sharing among a set of individuals, DNA Circles can serve as supporting evidence for documented pedigree lines.”  Notice, Ancestry did NOT SAY proof.  Nothing that Ancestry provides in their DNA product constitutes proof.

Ancestry continues by saying that Circles “opens the possibility for people to identify distant relatives with whom they do not share DNA directly but with whom they still have genetic evidence supporting the relationship.”

In other words, Ancestry is being very clear in this paper, which is provided on the DNA Circles page for anyone with Circles, that they are giving you a tool, not “the answer,” but one more piece of information that you can consider as evidence.

joel vannoy circleJoel Vannoy circle2

You can see in my Joel Vannoy circle that I match both of these people both genetically and on their tree.

We, in the genetic genealogy community, need proof.  It certainly could be available, technically – because it is with other vendors and third party sites.

We need to be able to prove that our matches also match each other, and utilizing Ancestry’s tools, we can’t.  We also can’t do this at Ancestry by utilizing third party tools, so we’re in essence, stuck.

We can either choose to believe, without substantiation, that we indeed share a common ancestor because we share DNA segments with them plus a pedigree chart from that common ancestor, or we can initiate a conversation with our match that leads to either or both of the following questions:

  1. Have you or would you upload your raw data to GedMatch?
  2. Have you or would you upload your raw data file to Family Tree DNA?

Let the begging begin!!!

The Problem

In a nutshell, the problem is that even if your Ancestry matches do reply and do upload their file to either Family Tree DNA or GedMatch or both, you are losing most of the potential information available, or that would be available, if Ancestry provided a chromosome browser and matrix type tool.

In other words, you’d have to convince all of your matches and then they would have to convince all of the matches in the circle that they match and you don’t to upload their files.

Given that, of the 44 private tree shakey leaf matches that I sent messages to about 2 weeks ago, asking only for them to tell me the identity of our common pedigree ancestor, so far 2 only of them have replied, the odds of getting an entire group of people to upload files is infinitesimal.  You’d stand a better chance of winning the lottery.

One of the things Ancestry excels at is marketing.

ancestry ad1

If you’ve seen any of their ads, and they are everyplace, they focus on the “feel good” and they are certainly maximizing the warm fuzzy feelings at the holidays and missing those generations that have gone before us.

ancestry ad2

This is by no means a criticism, but it is why so many people do take the Ancestry DNA test. It’s advertised as easy and you’ll learn more about your family.  And you do, no question – you learn about your ethnicity and you get a list of DNA matches, pedigree matches when possible and DNA Circles.

The list of what you don’t get is every bit as important, a chromosome browser and tools to see whether your matches also match each other.  However, most of their customers will never know that.

Judging by the high percentage of inaccurate trees I found at Ancestry in my little experiment relative to the known and documented wife’s name of James Lee Claxton, which was 96%, based on just the first page of 50 search matches, it would appear that about 96% of Ancestry’s clientele are willing to believe something that someone else tells them without verification.  I doubt that it matters whether that information is a tree or a DNA test where they are shown  matches with common pedigree charts and circles.  I don’t mean this to be critical of those people.  We all began as novices and we need new people to become interested in both genealogy and DNA testing.

I suspect that most of Ancestry’s clients, especially new ones, simply don’t have a clue that there is a problem, let alone the magnitude and scope.  How would they?  They are just happy to find information about their ancestor.  And as someone said to me once – “but there are so many of those trees (with a wrong wife’s name), how can they all be wrong?”  Plus, the ads, at least some of them, certainly suggest that the DNA test grows your family tree for you.

ancestry ad3 signoff

The good news in all of this is that Ancestry’s widespread advertising has made DNA testing just part of the normal things that genealogists do.  Their marketing expertise along with recent television programs have served to bring DNA testing into the limelight. The bad news is that if people test at Ancestry instead of at a vendor who provides tools, we, and they, lose the opportunity to utilize those results to their fullest potential.  We, and they, lose any hope of proving an ancestor utilizing DNA.  And let’s face it, DNA testing and genealogy is about collaboration.  Having a DNA test that you don’t compare against others is pointless for genealogy purposes.

When a small group of bloggers and educators visited Ancestry in October, 2014, for what came to be called DNA Day, we discussed the chromosome browser and Ancestry’s plans for their new DNA Circles product, although it had not yet been named at that time.  I wrote about that meeting, including the fact that we discussed the need for a chromosome browser ad nauseum.  Needless to say, there was no agreement between the genetic genealogy community and the Ancestry folks.

When we discussed the situation with Ancestry they talked about privacy and those types of issues, which you can read about in detail in that article, but I suspect, strongly, that the real reason they aren’t keen on developing a chromosome browser lies in different areas.

  1. Ancestry truly believes that people cannot understand and utilize a chromosome browser and the information it provides. They believe that people who do have access to chromosome browsers are interpreting the results incorrectly today.
  2. They do not want to implement a complex feature for a small percentage of their users…the number bantered around informally was 5%…and I don’t know if that was an off-the-cuff number or based on market research. However, if you compare that number with the number of accurate versus inaccurate pedigree charts in my “James Claxton’s wife’s name” experiment, it’s very close…so I would say that the 5% number is probably close to accurate.
  3. They do not want to increase their support burden trying to explain the results of a chromosome browser to the other 95%. Keep in mind the number of users you’re discussing. They said in their paper they had 500,000 DNA participants. I think it’s well over 700,000 today, and they clearly expect to hit 1 million in 2015. So if you utilize a range – 5% of their users are 25,000-50,000 and 95% of their users are 475,000-950,000.
  4. Their clients have already paid their money for the test, as it is, and there is no financial incentive for Ancestry to invest in an add-on tool from which they generate no incremental revenue and do generate increased development and support costs. The only benefit to them is that we shut up!

So, the bottom line is that most of Ancestry’s clients don’t know or care about a chromosome browser.  There are, however, a very noisy group of us who do.

Many of Ancestry’s clients who purchase the DNA test do so as an impulse purchase with very little, if any, understanding of what they are purchasing, what it can or will do for them, at Ancestry or anyplace else, for that matter.

Any serious genealogist who researched the autosomal testing products would not make Ancestry their only purchase, especially if they could only purchase one test.  Many, if not most, serious genealogists have tested at all three companies in order to fish in different ponds and maximize their reach.  I suspect that most of Ancestry’s customers are looking for simple and immediate answers, not tools and additional work.

The flip side of that, however, if that we are very aware of what we, the genetic genealogy industry needs, and why, and how frustratingly lacking Ancestry’s product is.

Company Focus

It’s easy for us as extremely passionate and focused consumers to forget that all three companies are for-profit corporations.  Let’s take a brief look at their corporate focus, history and goals, because that tells a very big portion of the story.  Every company is responsible first and foremost to their shareholders and owners to be profitable, as profitable as possible which means striking the perfect balance of investment and expenditure with frugality.  In corporate America, everything has to be justified by ROI, or return on investment.

Family Tree DNA

Family Tree DNA was the first one of the companies to offer DNA testing and was formed in 1999 by Bennett Greenspan and Max Blankfeld, both still principles who run Family Tree DNA, now part of Gene by Gene, on a daily basis.  Family Tree DNA’s focus is only on genetic genealogy and they have a wide variety of products that produce a spectrum of information including various Y DNA tests, mitochondrial, autosomal, and genetic traits.  They are now the only commercial company to offer the Y STR and mitochondrial DNA tests, both very important tools for genetic genealogists, with a great deal of information to offer about our ancestors.

In April 2005, National Geographic’s Genographic project was announced in partnership with Family Tree DNA and IBM.  The Genographic project, was scheduled to last for 5 years, but is now in its 9th year.  Family Tree DNA and National Geographic announced Geno 2.0 in July of 2012 with a newly designed chip that would test more than 12,000 locations on the Y chromosome, in addition to providing other information to participants.

The Genographic project provided a huge boost to genetic genealogy because it provided assurance of legitimacy and brought DNA testing into the living room of every family who subscribed to National Geographic magazine.  Family Tree DNA’s partnership with National Geographic led to the tipping point where consumer DNA testing became mainstream.

In 2011 the founders expanded the company to include clinical genetics and a research arm by forming Gene by Gene.  This allowed them, among other things, to bring their testing in house by expanding their laboratory facilities.  They have continued to increase their product offerings to include sophisticated high end tests like the Big Y, introduced in 2013.

23andMe

23andMe is also privately held and began offering testing for medical and health information in November 2007, initially offering “estimates of predisposition for more than 90 traits ranging from baldness to blindness.”  Their corporate focus has always been in the medical field, with aggregated customer data being studied by 23andMe and other researchers for various purposes.

In 2009, 23andMe began to offer the autosomal test for genealogists, the first company to provide this service.  Even though, by today’s standards, it was very expensive, genetic genealogists flocked to take this test.

In 2013, after several years of back and forth with 23andMe ultimately failing to reply to the FDA, the FDA forced 23andMe to stop providing the medical results.  Clients purchasing the 23andMe autosomal product since November of 2013 receive only ethnicity results and the genealogical matching services.

In 2014, 23andMe has been plagued by public relations issues and has not upgraded significantly nor provided additional tools for the genetic genealogy community, although they recently formed a liaison with My Heritage.

23andMe is clearly focused on genetics, but not primarily genetic genealogy, and their corporate focus during this last year in particular has been, I suspect, on how to survive, given the FDA action.  If they steer clear of that landmine, I expect that we may see great things in the realm of personalized medicine from them in the future.

Genetic genealogy remains a way for them to attract people to increase their data base size for research purposes.  Right now, until they can again begin providing health information, genetic genealogists are the only people purchasing the test, although 23andMe may have other revenue sources from the research end of the business

Ancestry.com

Ancestry.com is a privately held company.  They were founded in the 1990s and have been through several ownership and organizational iterations, which you can read about in the wiki article about Ancestry.

During the last several years, Ancestry has purchased several other genealogy companies and is now the largest for-profit genealogy company in the world.  That’s either wonderful or terrible, depending on your experiences and perspective.

Ancestry has had an on-again-off-again relationship with DNA testing since 2002, with more than one foray into DNA testing and subsequent withdrawal from DNA testing.  If you are interested in the specifics, you can read about them in this article.

Ancestry’s goal, as it is with all companies, is profitability.  However, they have given themselves a very large black eye in the genetic genealogy community by doing things that we consider to be civically irresponsible, like destroying the Y and mitochondrial DNA data bases.  This still makes no sense, because while Ancestry spends money on one hand to acquire data bases and digitize existing records, on the other hand, they wiped out a data base containing tens of thousands of irreplaceable DNA records, which are genealogy records of a different type.  This was discussed at DNA Day and the genetic genealogy community retains hope that Ancestry is reconsidering their decision.

Ancestry has been plagued by a history of missteps and mediocrity in their DNA products, beginning with their Y and mitochondrial DNA products and continuing with their autosomal product.  Their first autosomal release included ethnicity results that gave many people very high percentages of Scandinavian heritage.  Ancestry never acknowledged a problem and defended their product to the end…until the day when they announced an update titled….a whole new you.  They are marketing geniuses.  While many people found their updated product much more realistic, not everyone was happy.  Judy Russell wrote a great summary of the situation.

It’s difficult, once a company has lost their credibility, for them to regain it.

I think Ancestry does a bang up job of what their primary corporate goal is….genealogy records and subscriptions for people to access those records. I’m a daily user.  Today, with their acquisitions, it would be very difficult to be a serious genealogist without an Ancestry subscription….which is of course what their corporate goal has been.

Ancestry does an outstanding job of making everything look and appear easy.  Their customer interface is intuitive and straightforward, for the most part. In fact, maybe they have made both genealogy and genetic genealogy look a little too easy.  I say this tongue in cheek, full well knowing that the ease of use is how they attract so many people, and those are the same people who ultimately purchase the DNA tests – but the expectation of swabbing and the answer appearing is becoming a problem.  I’m glad that Ancestry has brought DNA testing to so many people but this success makes tools like the chromosome browser/matrix that much more important – because there is so much genealogy information there just waiting to be revealed.  I also feel that their level of success and visibility also visits upon them the responsibility for transparency and accuracy in setting expectations properly – from the beginning – with the ads. DNA testing does not “grow your tree” while you’re away.

I’m guessing Ancestry entered the DNA market again because they saw a way to sell an additional product, autosomal DNA testing, that would tie people’s trees together and provide customers with an additional tool, at an additional price, and give them yet another reason to remain subscribed every year.  Nothing wrong with that either.  For the owners, a very reasonable tactic to harness a captive data base whose ear you already have.

But Ancestry’s focus or priority is not now, and never has been, quality, nor genetic genealogy.  Autosomal DNA testing is a tool for their clients, a revenue generation source for them, and that’s it.  Again, not a criticism.  Just the way it is.

In Summary

As I look at the corporate focus of the three players in this space, I see three companies who are indeed following their corporate focus and vision.  That’s not a bad thing, unless the genetic genealogy community focus finds itself in conflict with the results of their corporate focus.

It’s no wonder that Family Tree DNA sponsors events like the International DNA Conference and works hand in hand with genealogists and project administrators.  Their focus is and always has been genetic genealogy.

People do become very frustrated with Family Tree DNA from time to time, but just try to voice those frustrations to upper management at either 23andMe or Ancestry and see how far you get.  My last helpdesk query to 23andMe submitted on October 24th has yet to receive any reply.  At Family Tree DNA, I e-mailed the project administrator liaison today, the Saturday after Thanksgiving, hoping for a response on Monday – but I received one just a couple hours later – on a holiday weekend.

In terms of the chromosome browser war – and that war is between the genetic genealogy community and Ancestry.com, I completely understand both positions.

The genetic genealogy community has been persistent, noisy, and united.  Petitions have been created and signed and sent to Ancestry upper management.  To my knowledge, confirmation of any communications surrounding this topic with the exception of Ancestry reaching out to the blogging and education community, has never been received.

This lack of acknowledgement and/or action on the issues at hand frustrates the community terribly and causes reams of rather pointed and very direct replies to Anna Swayne and other Ancestry employees who are charged with interfacing with the public.  I actually feel sorry for Anna.  She is a very nice person.  If I were in her position, I’d certainly be looking for another job and letting someone else take the brunt of the dissatisfaction.  You can read her articles here.

I also understand why Ancestry is doing what they are doing – meaning their decision to not create a chromosome browser/match matrix tool.  It makes sense if you sit in their seat and now have to look at dealing with almost a million people who will wonder why they have to use a chromosome browser and or other tools when they expected their tree to grow while they were away.

I don’t like Ancestry’s position, even though I understand it, and I hope that we, as a community, can help justify the investment to Ancestry in some manner, because I fully believe that’s the only way we’ll ever get a chromosome browser/match matrix type tool.  There has to be a financial benefit to Ancestry to invest the dollars and time into that development, as opposed to something else.  It’s not like Ancestry has additional DNA products to sell to these people.  The consumers have already spent their money on the only DNA product Ancestry offers, so there is no incentive there.

As long as Ancestry’s typical customer doesn’t know or care, I doubt that development of a chromosome browser will happen unless we, as a community, can, respectfully, be loud enough, long enough, like an irritating burr in their underwear that just won’t go away.

burr

The Future

What we “know” and can do today with our genomes far surpasses what we could do or even dreamed we could do 10 years ago or even 5 or 2 years ago.  We learn everyday.

Yes, there are a few warts and issues to iron out.  I always hesitate to use words like “can’t,” “never” and “always” or to use other very strongly opinionated or inflexible words, because those words may well need to be eaten shortly.

There is so much more yet to be done, discovered and learned.  We need to keep open minds and be willing to “unlearn” what we think we knew when new and better information comes along.  That’s how scientific discovery works.  We are on the frontier, the leading edge and yes, sometimes the bleeding edge.  But what a wonderful place to be, to be able to contribute to discovery on a new frontier, our own genes and the keys to our ancestors held in our DNA.

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Disclosure

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

Thank you so much.

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Introducing the Autosomal DNA Segment Analyzer

We have a brand new toy in our DNA sandbox today, thanks to Don Worth, a retired IT professional.  I just love it when extremely talented people retire and we, in the genetic genealogy community, are the benefactors of their Act 2 evolution.  Our volunteers make such a cumulative difference.

Drum Roll please.

Introducing…..the Autosomal DNA Segment Analyzer, or ADSA.

The name alone doesn’t make your heart skip beats, but the product will.  This tool absolutely proves the adage that a picture is worth 1000 words.

Don described his new tool, which, by the way, is free and being hosted by Rob Warthen at www.dnagedcom.com, thus:

I created this tool in an attempt to put all the relevant information available that was needed to evaluate segment matches on a single, interactive web page. It relies on the three files for a single test kit that DNAgedcom.com collects from FamilyTreeDNA.com. These files include information about your matches, matching segment locations and sizes, and “in common with” (ICW) data. Using these files, the tool will construct a table for each chromosome which includes match and segment information as well as a visual graph of overlapping segments, juxtiposed with a customized, color-coded ICW matrix that will permit you to triangulate matching segments without having to look in multiple spreadsheets or on different screens in FamilyTreeDNA. Additional information, such as ancestral surnames, suggested relationship ranges, and matching segments and ICWs on other chromosomes is provided by hovering over match names or segments on the screen. Emails to persons you match may also be generated from the page. The web page produced by this program does not depend on any other files and may be saved as a stand-alone .html file that will function locally (or offline) in your browser. You can even email it to your matches as an attachment. You can play with a working sample output here.

Who wants to play with sample output?  I wanted to jump right in.  Word of caution…read the instructions FIRST, and pay attention, or you’ll wind up downloading your files twice.  The instructions can be found here.

I can’t tell you how many times, when I’ve been working with matches, that I’ve wondered to myself, “How many other people match us on this segment?”  For quite a while you could only download 5 people at a time, but now you can download the entire data file.  I’m a visual person.  To me, visually seeing is believing and the ADSA makes this process so much easier.  Truly, a picture is worth 1000 words.

I knew right away there were three things I wanted to do, so I’m going to run through each one of the three by way of examples to illustrate what you can do with the power of this wonderfully visual tool.  I’ve also anonymized the matches.

1. Clusters of matches.

I know I’ve told you that I’m mapping my DNA to ancestors.  When I first saw Don’s output, I knew immediately that this tool would be invaluable for grouping people from the same ancestral lines.

Barbara, the second row, is my mother and her DNA in this equation is extremely useful.  It helps me identify right away which side of my family a match comes from.  If you don’t have a parent available, aunts, uncles, cousins, all help, especially cumulatively.

Before we begin working with the results, take a minute and just sit and look at the graphic below.  These two clusters shown on this page, one near the top and the other at the bottom….they represent your ancestors.  Two very different ones in this case. This may be the only way you’ll ever “see” them, by virtue of a group of their descendants DNA clustered together.  A view through the keyhole of time provided by DNA. Isn’t it beautiful?

adsa cluster 1

All of these results in this “cluster of matches” example are my matches.  In other words, the file is mine and these are people who are matching me.  You can see that this tool provides us with start and end segments, total cMs and SNPs, and e-mails, but the true power is in the visual representation of the ICW (in common with) matrix.  The mapped segments are a nice touch too, and Don has listed these in progressive order, meaning from beginning to end of the segment (left to right.)

Look at this initial clustered group, shown enlarged below.  The first individual matches me and mother on one pink segment, but matches me on two segments, a pink and a black.  That means he’s from Mom’s side, or at least through one line, but probably somewhat distant since that one segment is his only match on any chromosome.  Because he also matches me on a segment where he doesn’t match Mom, he could also be related to me on my father’s side, or maybe we had a misread error on the black segment when comparing to Mom’s DNA. It is the adjoining segment.  In essence, there isn’t enough information to do much with this, except ask questions, so let’s move on to something more informative.

Beginning with the third person, the next grouping or cluster is entirely non-matching to mother, so this entire cluster is from my father’s side AND related to each other.

There are 6 solid matches here, and then they start to trail off to matches that aren’t so solid.

ADSA cluster 1 A

By flying over the match names with my cursor, I might be able to tell, based on their surnames, which line is being represented by this cluster of matches.  If I already have a confirmed cousin match in the group, then the rest of the group can be loosely attributed to that line, or a contributing (wife) line. Unfortunately, in this case, I can’t tell other than it looks like it might be through Halifax County, VA.  I do have an NPE there and some wives without surnames.

Let’s look on down this chromosome.  There is another very solid cluster, also on my Dad’s side.  In this second cluster, I have identified a solid cousin and I can tell you that this is a Crumley grouping.  My common ancestor with my Crumley cousin is William Crumley born about 1765 in Frederick Co., Va. and who died about 1840 in Lee Co., Va.  His wife is unknown, but we have her mitochondrial DNA.  Now this doesn’t mean that everyone in this group will all have a Crumley ancestor, they may not.  They may instead have a Mercer, a Brown, a Johnson or a Gilkey, all known wives’ surnames of Crumley men upstream of William Crumley.  But someplace, there is a common ancestor who contributed quite a bit of chromosome 1 to a significant number of descendants, and at least two of them are Crumleys.

ADSA Crumley cluster

At first, I found it really odd that my mother had almost no matches with me on chromosome 1.  Some of my mother’s ancestors came to the States later, from the Netherlands and from Germany.  Many of these groups are under-represented in testing.  However other ancestral groups have been here a long time, Acadians and Brethren Germans.  My father’s Appalachian, meaning colonial, ancestors seem to have more descendants who have tested.

However, looking now at chromosome 9, we see something different.

ADSA Acadian cluster

The second person, Doris, doesn’t match Mom anyplace, so is obviously related through my father, but look at that next grouping.

I can tell you based on hovering over the matches name that this is an Acadian grouping.  The Acadians are a very endogamous French-Canadian group, having passed the same DNA around for hundreds of years.  Therefore, a grouping is likely to share a large amount of common DNA, and this one does.

ADSA Acadian flyover

Based on this, I can then label all of these various matches as “Acadian” if nothing more.

Within a cluster, if I can identify one common ancestor, I can attribute the entire large group to the same lineage.  Be careful with smaller groups or just one or two rectangle matches.  Those aren’t nearly as strong and just because I match 2 people on the same segment doesn’t mean they match each other. However, when you see large segments of people matching each other, you have an ancestral grouping of some sort.  The challenge of course is to identify the group – but a breakthrough with one match means a likely breakthrough with the rest of them too, or at least another step in that direction.

2. Source of DNA

I have several cousins who match me on two or more distinct lines.  This tool makes it easy, in some cases, to see which line the DNA on a particular chromosome comes from.

I have both Claxton (James Lee Claxton/Clarkson born c 1775-1815 and Sarah Cook of Hancock Co., TN)  and Campbell (John Campbell b c 1772-1838 and Jane Dobkins born c 1780-1850/1860 of Claiborne Co., Tn.) ancestry.  My cousins, Joy and William do too.  In this case, you can see that Joy matches a Claxton (proven by Y DNA to be from our line) and so does William on the first green matching segment.  The second green segment is not found in the Claxton match, so it could be Claxton and the Claxton cousin didn’t receive it, or it could be Campbell, but it’s one or the other because Joy, William and I all three carry this segment.

ADSA Claxton Campbell

What this means is that the light green segments are Claxton segments, as are the fuchsia segments.  The source of the darker green segment is unknown.  It could be either Claxton or Campbell or a third common line that we don’t know about.

3.  Untangling Those Darned Moores

I swear, the Moore family is going to be the death of me yet. It’s one of my long-standing, extremely difficult brick walls.  It seems like every road of every county in Virginia and NC had one or more Moore families.  It’s a very common name.  To make thing worse, the early Moores were very prolific and they all named their children the same names, like James and William, generation after generation.

The earliest sign I can find of my particular Moore family is in Prince Edward County, Virginia when James Moore married Mary Rice (daughter of Joseph Rice and wife Rachel) in the early 1740s.  By the 1770s, the family was living in Halifax County, Virginia and their children were marrying and having children of their own of course.  They were some of the early Methodists with their son, the Reverend William Moore being a dissenting minister in Halifax County and his brothers Rice and Mackness Moore doing the same in Hawkins and Grainger County, TN.  Another son, James, went to Surry Co., NC.  We have confirmed this with a DNA descendant match.

We have the DNA of our Moore line proven on the Y side through multiple sons.  At the Moore Worldwide DNA project, we are group 19.  Now there are Moores all over the place in Halifax County.  I know, because I’ve paid for about half of them to DNA test and there are several distinct lines – far more than I expected.  Ironically, the Anderson Moore family who lived across the road from our James and then his son Rev. William, who raised the orphan Raleigh Moore, grandson of the Rev. William Moore, is NOT of the same Moore DNA line.  Based on the interaction of these two families, one would think assuredly that they were, which raises questions.  This Anderson Moore was the son of yet another James Moore, this one from Amelia County, VA., found in the large group 1 of the Moore project.  If this is all just too confusing and too close for comfort for you, well, join the crowd and what we Moore descendants have been dealing with for a decade now.

This raises the question of why there are so few matches to our Moore line.  Was our Moore line a “new Moore line,” born perhaps to a Moore daughter who gave the child her surname.  However, the child of course would pass on the father’s Y chromosome, establishing a “new” Moore genetic line.  I’m not saying that is what happened, just that it’s odd that there are so few matches to a clearly colonial Moore line out of Virginia.  With only one exception, someone genealogically stuck in Kentucky, to date, all DNA matches are all descendants of our James.  We do know that there was a William Moore, wife Margaret, living adjacent to James Moore in Prince Edward County but he and his wife sold out and moved on and are unaccounted for.

I’ve seen this same pattern with the Younger family line too, and sure enough, we did prove that these two different Y chromosome Younger families in fact do share a common ancestor.

So you can see why I get excited when I find anything at all, and I mean anything, about the Moore family line.

A Moore descendant of Raleigh, the orphan, has taken the autosomal Family Finder test, and he matched my cousin Buster, a known Moore descendant, and also another Cumberland Gap region researcher, Larry.  Larry also matches Buster.  I was very excited to see this three way match and I wrote to Larry asking if he had a Moore line.  Yes, he did, two in fact.  The Levi Moore line out of Kentucky and an Alexander Moore line out of Stokes County, NC, after they wandered down from Berks Co., PA. sometime before 1803.

Groan. Two Moores – I can’t even manage to sort one out, how will I ever sort two?

Then Larry told me that he had 4 of his cousins tested too.  Bless you Larry.

And better yet, one of Larry’s Moore lines is on his mother’s side and one on his father’s.  Even better yet.  Things are improving.

Now I’m really excited, right up until I discover that my cousin Buster matches two of Larry’s 3 cousins on his mother’s side and my Moore cousin from Halifax County, Virginia, matches the cousin on Larry’s father’s side.

How could I be THIS unlucky???

So I started out utilizing the ICW and Matrix tools at Family Tree DNA.  Because these people all matched Larry on overlapping segments on the chromosome browser, my first thought was maybe that these two Moore lines were really one and the same.  But then I pushed the ICW matches through to the Family Finder Matrix, and no, Larry’s paternal cousin does not match any of the three maternal cousins, who all match each other.  So the two Moore families are not one and the same.

Crumb.  Thank Heavens though for the Matrix which provides proof positive of whether your matches match each other.  Remember, you have two sides to each chromosome and you will have matches to both sides.  Without the Matrix tool, you have no way of knowing which of your matches are from the same side of your chromosome, meaning Mom’s side or Dad’s side.

Just about this time, as I was beginning to construct matrixes of who matches whom in the ICW compares between all of the ICW match permutations, I received a note from Don that he wanted beta testers for his new ADSA application.  I immediately knew what I was going to test!

I started with my cousin Buster’s kit.  Buster is one generation upstream from me, so one generation closer to the Moore ancestors.

On Larry’s maternal line, descended from the Levi Moore (Ky) line, he tested three cousins.  Buster had the following match results with Larry and his maternal line cousins.

  • Larry – match
  • Janice  – no match
  • Ronald  – match
  • B.J.  – match

I have redacted the e-mails and surnames below, but want to draw your attention to the individuals with the red arrows, as noted above.ADSA1 cropped v2

On the graphic below, I’m showing only the right side, so you can see the matching ICW (in common with) block patterns.  Larry is last, I’m second from last and Larry’s two cousins are the first and second red arrows.  We are all matching to my cousin, Buster.

ADSA2 cropped

You can see that all of these people match Buster.  Larry has blocks that are pink, red, fuchsia, gold, navy blue and lime green.  All of the group above, except me and two other people, one of which is my known cousin on another line, match Larry on these blocks, or at least most of these blocks.  I, however, match none of this group on none of these blocks, nor do my other known cousins who also descend through this same Moore line.  This means that this group matches Buster through Buster’s mother’s line, not through the Estes line, which means that this Moore line is not the James Moore line of Halifax County.  So the Levi Moore group of Kentucky is not descended from the James Moore group of Prince Edward and Halifax County.

Of course, I’m disappointed, but eliminating possibilities is just as important as confirming them.  I keep telling myself that anyway.

The male Moore descendant in Halifax Co., proven via Y line testing, does match with Chloa, Larry’s paternal cousin, and with Larry as well, as shown below.  Let’s see if we can discern any other people who match in a cluster, which would give us other people to contact about their Moore lines.  Keep in mind that we don’t know that the DNA in common here is from the Moore line.  It could come from another common line.  That is part of what we’d like to prove.

ADSA3

Let’s take a closer look at what this is telling us.

First, there’s a much smaller group, and this is the only chromosome where Chloa matches our Moore cousin.

So let’s look at each line.  The first person, John, doesn’t match anyone else, so he’s not in this group.

Larry and his cousin, Chloa are second and third from the bottom, and they form the match group.  You can see that they match exactly except Chloa has one brighter green segment that matches our Moore cousin in a location with no other matches.  However, the match group of navy blue, periwinkle, lime green and burgundy form a distinctive pattern.  In addition to Chloa and Larry, Virginia, and Arlina share the same segments, plus Arlina had a pink segment that Larry and Chloa don’t have.  Donald may be a cousin too, but we don’t know if Donald would also match the rest of the group.  Linda might match Donald, but doesn’t look like she matches the group, but she could.  At this point, we can drop back to Family Tree DNA and the matrix and take a look to see if these folks match each other in the way we’d expect based on the ADSA tool.

ADSA Matrix

Just like we expected, John doesn’t match anyone.  As expected, Larry, Chloa, Arlina, and Virginia all matched each other.  As it turns out, Linda does not match the rest of the group, but she does match Donald, who does match Arlina.  Therefore, our focus needs to be on contacting Arlina, Donald and Virginia and asking them about their Moore lines, or the surnames of known Moore wives, such as Rice in my James Moore line or wives surnames in Larry’s Moore line.  Just on the basis of possibility, I would also contact Linda and ask, but she is the long shot.  However, like the lottery, you can’t win if you don’t play, so just send that one extra e-mail.  You never know.  Life is made up of stories about serendipity and opportunities almost missed.

If Larry’s Moore line is the same as our Moore cousin’s line, genetically, maybe we can make headway by tracking Larry’s line.  Larry was kind enough to provide me with a website, and his Moore line begins with daughter Sarah.  Her father is Alexander Moore born in 1730 who married Elizabeth Wright.  His father was Alexander born in 1710 and who lived in Bucks Co., PA.  The younger Alexander died in Stokes Co., NC in 1803.

Moore website 1 cropped

Moore website 2

Moore website 3

Our next step is to see if this Alexander Moore line has been Y DNA tested.  Checking back at the Moore Worldwide project, this family line is not showing, but I’ve dropped a note to the administrators,  just the same.  Unfortunately, not everyone enters their most distant ancestor information which means that information is blank on the project website.

If this Alexander Moore line has been Y tested, then we already know they don’t match our group paternally.  The connection, in that case, if this genetic connection is a Moore line, could be due to a daughter birth.  If this Moore line has not been Y tested, then it means that I’ll be trying to track down a Moore descendant of one of these Alexander Moores to do the DNA test.  It would be wonderful to finally make some headway on the James Moore family.  We’ve been brick walled for such a long time.

If you descend from either of these Moore family lines, the James Moore (c 1720-c 1798) and Mary Rice line, or the Alexander Moore and Elizabeth Wright or Elizabeth Robinson line, please consider taking the Family Finder autosomal DNA test at Family Tree DNA.  If you know of a male Moore who descends from the Alexander Moore line, let’s see if he would be willing to Y DNA test.

There is a great deal of power in the combined results of descendants, as you can clearly see, thanks to Don Worth and his new Autosomal DNA Segment Analyzer tool.

Give it a test run at: http://www.DNAgedcom.com/adsa

Don wrote documentation and instructions, found here.  Please read them before downloading your files.

And Don, a big, hearty thank you for this new way to “see” our ancestors!  Thank you to Rob Warthen too for hosting this wonderful new tool!

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Disclosure

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

Thank you so much.

DNA Purchases and Free Transfers

Genealogy Services

Genealogy Research

One Chromosome, Two Sides, No Zipper – ICW and the Matrix

ZipperThe questions I’ve received most often since the release of the new Family Finder Matrix from Family Tree DNA has to do with matches.  Specifically, what the “In Common With” feature is telling you versus what the Family Finder “Matrix” is telling you and how to utilize all of this information together.  At the bottom of this confusion is often a fundamental lack of understanding of how matching occurs and what it means in different contexts.

Let’s talk about this, step by step.

The “in common with” function (called triangulation for a few weeks, but now labeled “run common matches” ) shows you every person that you and one of your matches, match with in common.  I’ll be running this option for my matches with cousin David, shown below.

zipper 1

Here’s an example of my matches in common with my cousin, David.

Zipper 2

The Family Finder Matrix takes this information a bit further and shows you whether or not the people involved with this match, match each other as well.

In this case, I happen to know that my cousins Harold, Carl and Dean will match each other on my father’s side, as will my cousin David.  Warren doesn’t have firm genealogy, but from this, we can tell that he is indeed connected to this family group because he matches me, David, Harold and Carl, but not Dean and not Nova.  We have no idea how Nova connects to this line, if she does.  Notice that Nova does not match any of the other people in this group in the matrix below.  That means that my and David’s common ancestor with her is likely not from this same ancestral line shared by Harold, Carl and Dean.

zipper 3

From this point forward, I would drop back to my trusty downloaded full match spreadsheet that I maintain to see if indeed any of these people match me and my known cousins on the same segments.  If so, that confirms a family/ancestor relationship.   On the snipped from my spreadsheet below, you can see that Warren indeed matches both Buster and David and I, but not on the same segments.  Nova didn’t match any grouping on the same segments.  However, Buster and David both match me on the same portion of chromosome 19, so this confirms that we do share a common ancestor.  In this case, we also know, from our genealogy that the common ancestor is Lazarus Estes and wife, Elizabeth Vannoy.  Based on our multiple cousin matches, we can say that Warren is somehow connected to this line, but we can’t say how.

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I’ve had comments like “I have everything I need on my spreadsheet – I can see where all of my matches match me.”  And indeed, you can, but it’s not everything you need.  Here’s why.

Without additional information, you can’t tell, by just looking at your spreadsheet whether two people who match you on the same segment are matching on your Mom or Dad’s side.  For example, above, I know that both David and Buster are from my Dad’s line, but if I didn’t know that, one of them could be from Mom’s line and one could be from Dad’s, and while they are both related to me, on the same chromosome, they would, in that case, not be related to each other.  So, my spreadsheet of matches tells me clearly THAT people match me, and where, but it doesn’t tell me HOW or on which side.  For that, I need additional tools like ICW, the Matrix and plain old genealogy research.

This is the fundamental concept of matching and in a nutshell, why it’s so difficult.

Every Chromosome Has Two Sides

There are two sides to every chromosome, Mom’s side and Dad’s side.  Except nature has played a cruel trick on us and not installed a zipper.  There are no Mom and Dad labels.  There is no dividing that DNA or those matches in half magically, except by determing who they match, and how they do or don’t match each other.

When we match ourselves against our parents, for example, we then know immediately which half of our DNA came from which parent, but if you don’t have any parents available to match against, then you have to use genealogy or cousin matches to figure that out.

I talk about that in the Chromosome Mapping aka Ancestor Mapping article.

I’m going to use spreadsheets as examples here.  It think they are easier to see and understand, plus, I can manipulate them easily to reflect different situations.

Example 1 – The Very Basics of Matching

At each DNA location, or address, you have two alleles, one from each parent.  These alleles can have one of 4 values, or nucleotides, at each location, represented by the abbreviations T, A, C and G, short for Thymine, Adenine, Cytosine and Guanine.  That’s it, you’re done with all the science words now, so keep reading:)

On any given chromosome, from locations 1-20, you have the following DNA, in our example.

From Mom, you received all As and from Dad, all Cs.  You know that because I’m telling you, but remember, the matching software doesn’t know that because there is no zipper in your DNA.  All the software sees are that you have both an A and an C in location 1 and either an A or C is considered a match.

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In fact, this is what the software sees.  Be aware that in this case, AC=CA.

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Easy so far, right?

Example Two – Mom’s Known Cousin and Dad’s Known Cousin

Now you have two cousins, Mary and Myrtle.  You know, from having known them all of your life and sharing lots of Thanksgiving turkey that they are your family and you know clearly which side of your family they descend from.  Both of your cousins, Mary and Myrtle match you at the same locations on this chromosome, from 5-15.

But Mary is your mother’s cousin, and Myrtle is your Dad’s cousin.  So even though they both match you on the same exact chromosome and the same location, they do not match each other.  Well, let’s put it this way, if they also match each other, then you have an entirely different family genetic genealogy problem, called endogamy, and yes, you might be your own grandpa…but I digress.  But we’re going to assume for this discussion that your mother and father are not related to each other and do not share common ancestors.

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Still easy, right?

Example Three – An Unknown Cousin

Next, we have Martha.  You don’t know Martha, and you don’t know how she is related, but she obviously is.  Martha matches you, but she does not match Myrtle at all, and she doesn’t match Mary on enough overlapping chromosomes to be considered a match to her.  You can see their common match here between Mary and Martha in location 5.  In this case, as it turns out, Martha IS a cousin to Mary on Mom’s side, but we can’t tell that from this information because they don’t match in enough common locations to be above the matching threshold.  With this information, you can’t draw any conclusions.  You will have to wait to see who else Martha matches and look on your spreadsheet to see if Martha matches any of your known cousins and you on common segments which would confirm a common ancestor.  Your download spreadsheet will contain much more detailed information because once you match on any segment above the match threshold of about 7.7cM (plus a few other factors,) all matching segments of 1cM or above are downloaded – so you have a lot of information to work with.

But using both the ICW and matrix tools, Mary might cluster with other cousins on Mom’s side which would provide us with clues as to her relationship.  In fact, the first thing I’d do is to run an ICW with Mary and then utilize the Matrix tool to further define those relationships.

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Still not difficult.

Example Four – A “False Match”

Next we have Jeremy who is also a match to you.

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If you look at how Jeremy matches, you can see that he is actually matching on both sides, Mom’s and Dad’s side, but randomly.  Technically, he is a match to you, because he does match one or the other of your nucleotides at each location, A or C, but without a zipper, we have no idea HOW that DNA is divided in you between Mom and Dad.  In other words, the software doesn’t know that Mom was all A and Dad was all C, unless we’ve phased the data against your parents AND the software knows how to utilize that information.

However, if your parents are one of your matches, you can immediately see which side the match falls on, if either.  In this case, Jeremy doesn’t fall on either side because he is simply a circumstantial match, also known as a match my convergence or a false match.  This is also called IBS, or identical by state, as opposed to IBD, identical by descent.  The smaller the segment you show as a match, especially if there is no clustering, the more likely the match is to be IBS instead of the genealogically desirable IBD.

When people ask how someone can match a child but not a parent, this is the answer.  He matches you on 11 segments, circumstantially, but he only matches your parents on 5 and 6 segments, respectively, which often (but not always) puts him under the matching threshold.  Jeremy may also match Mary, depending on the thresholds.

This is also how someone can match in the “in common with” tool, but not be a match to anyone on the match list in the Matrix.  In fact, this is the power of these multiple tools.

This also doesn’t mean this match is entirely useless, because you DO match.  It may simply not be relevant genealogically.  In “The Autosomal Me” series, I’ve utilized very small match segments that in fact very probably ARE reflective of a common population and not of recent ancestry.  In my Native American research, this is exactly what I was looking for.  You may not be able to utilize this information today, but don’t entirely discount it either.  Just set it aside and move on to a more productive match.

Example Five – Common Matches, Different Ancestors

This situation provides clues, but no proof.

Mary and Joyce both match me on Mom’s segments, but they do not match each other.  They don’t match me on the same segments, so this indicates that they are probably from different ancestors in my Mother’s lines.  As more matches appear, the clusters of people and their genealogy will make this more apparent.

In order to determine which ancestors, I’ll need to work on the genealogy of both Mary and Joyce and see who else they also match on the same segments.  Sometimes the secret of the genealogy match is in the genealogy research or descent of your matches.

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Example Six – Clusters of Cousins

In this example, no one matches Dad, so he’s just out for now.  Susie and Mary match mom on the same segment, which proves that the three of these people share a common ancestor.  Mom and Joyce match each other too, but Joyce doesn’t match Mary and Susie, so they won’t cluster together on the matrix.  However, on the ICW tool, all three women, Joyce, Mary and Susie will match me and Mom.

Using the ICW tool if I were to ICW with Mom, you would see this list:

  • Joyce
  • Mary
  • Susie

The question then becomes, are Joyce, Mary and Susie related to each other, or not.  If so, and to me and Mom, then that indicates a common ancestor within the match group, like me, Joyce and Mom.  The second group doesn’t match the first group – me, Mary, Mom and Susie.  Using these tools together, these people clearly fall into two match groups, the green and blue on the spreadsheet below.  But remember, the match routine doesn’t know which side your As and Cs came from.  All it knows is that you match these people.  But based on these groups and my download spreadsheet common segment matches, I can tell that I’m working with two ancestral lines.

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My matrix for these people would look like this:

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My master matching spreadsheet would now look like this.

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When we started, all I would have been able to see is that all of these people matched Mom and Dad and I on the same segments. By utilizing the various tools, I was able to sort into groups and eventually, subgroups.

In fact, you can see below that within Mom’s pink group, there is also the smaller cluster of Mary, Susie, me and Mom.

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For Jeremy and Martha, we can’t do any more right now, so I’ve recorded what we do know and set them aside.

Here, you can see the matches sorted by chromosome, start and end segment.

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It looks a lot different than where we started, shown below, when all we had was a list of people who matched each other with no additional information.  We’ve added a lot!

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In Summary – Creating the Zipper

So, where are we with this?

By utilizing all of the tools at your disposal, including the ICW tool, the Family Finder Matrix, your matching spreadsheet and your genealogical information, you’re in essence creating that zipper that divides half of your DNA into Mom’s side and Dad’s side.  Then into grandma’s and grandpa’s side, and on up the pedigree chart.

Each of these tools can tell you something unique and important.

The ICW tool tells you who matches you and another person, in common.  It doesn’t tell you if they also match each other.  This tool can provide extremely important clustering information.  For example, if I see unknown cousin Martha clustered with a whole group of known Estes descendants, then that’s a pretty good clue about how I’m related to Martha.  If, on the other hand, I find Martha clustered with people from both sides of my family, well, my Mom and Dad just might be related to each other or their ancestors went to or came from the same places.

By utilizing the Matrix tool, I can tell which of my matches are actually matching each other too, so that puts Martha in a much smaller group, or maybe eliminates her from certain groups.

By then utilizing my downloaded match spreadsheet, on which I record every known tidbit of genealogy information, even generalities like, “family from NC” if that’s the best I can get, I can then see where Martha matches me and others on the same segments, and based on the information in the ICW and the Matrix and my genealogy info, I may be able to slot Martha into a family group.  On a great day – I’ll be able to be more specific and tell her which family group – like we were able to do with my newly found cousin, Loujean.

So, I hope you’ve enjoyed learning how to install a chromosome zipper.  Now you can happily go about unzipping all of that genealogy information held in your DNA, that piece by piece, we’re slowing revealing.

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