So I’m starting to explore AncestryDNA’s ‘Shared Matches’ tool…

I’ve recently started to explore AncestryDNA’s  ‘Shared Matches’ feature. By recent, I mean only 48 hours ago. Explorations like this makes my inner geek happy. I’ve tinkered with digital stuff and technology for years, so tech like this isn’t daunting to me. I fearlessly dive in to see how things work…or least try to figure out how things like this tool work.

I offer this caveat up-front: I’ll be covering the ‘Shared Matches’ feature as it appears on the new Ancestry / AncestryDNA site. So please don’t be thrown or confused when looking at the screen grabs. They will look very different from the old version of the site, if that’s the one you’re still using.

I’m just exploring and working things out at the moment. There is an end game for this exploration. I hope I can make some in-roads into my Irish and Ashkenazi Jewish genealogy. Yes, that’s right, I have 3 of the most challenging ethnicities to research when it comes to genealogy: African-American, Irish and Central/Eastern European Jewish. Three ethnicities that have undergone a worldwide diaspora with some of the most challenging records to find. That’s me. If there is a genealogy higher power, s/he must be laughing.

What better way to finely hone my pending approach to tackling my unknown Irish and Jewish ancestors than a thorough understanding of how this feature works with my known African-American cousins and known European cousins? I can then apply this insight to DNA cousins I have yet to find common ancestors for. If I can understand the strengths and weaknesses of the ‘Shared Matches’ algorithm and results, I can have a more informed  approach to understanding the many Irish and Jewish DNA cousins I have on AncestryDNA. I have a staggering number of each.

That’s my working premise at the moment.

Ok, with that out of the way, let me show you how I’ve been exploring this AncestryDNA tool.

Below is the standard AncestryDNA family matches landing page. No surprises here for those of you familiar with the service. And yes, your eyes aren’t deceiving you. I really do have 49 pages of DNA cousin matches.

image showing my AncestryDNA family matches landing page
My AncestryDNA family DNA match landing page. Please note that I have will be protecting the identities of my DNA matches in this post. Click for a larger image

Now I have a LOT of cousins with connections to what was the Old Ninety-Six County of South Carolina (this county was dissolved to create the following counties: Abbeville, McCormick, Edgefield, Saluda, Greenwood, Laurens, and Union counties, parts of  Spartanburg County; much of Cherokee and Newberry counties; and small parts of Aiken and Greenville Counties). I know exactly how I’m related to a number of these 3rd, 4th and 5th cousins. There’s a group of us who are very, very active genealogy researchers and share information of various family groups on Facebook.

I connect to these cousins in a myriad of ways. We are the descendants of enslaved Africans, free people of colour and Quakers who left England and Scotland for Antrim and Ulster in northern Ireland, made their way to Pennsylvania and later the former Old Ninety-Six. Knowing how we’re related tells me a bit about how ‘Shared Matches’ works.

And, in a way, my Edgefield family heritage is a good one when it come to understand this DNA matching analysis tool. Whether Quaker, formerly Quaker or African-American, my Edgefield ancestors and relations married within the extended family for generations. So many of my Edgefield-connected cousins and I, regardless of ethnicity, are related to one another a few times over (so far, the winner is a cousin I’m related to at least 4 different ways). Why is this important to note? There are few single sets of common ancestors when it comes to the Edgefield side of my family tree. Which makes pinpointing isolated common ancestors a bit tricky. I’m going to find the same pattern for my rural, agricultural Irish ancestors (who married within a clan structure) and my Ashkenazi Jewish ancestors. Edgefield, it turns out, will be a great genetic genealogy proving ground. It really is as complicated and intricate as general genealogy, much less genetic genealogy, gets.

So, I want to see how many DNA cousins there are who also share a connection to Edgefield. So I typed this search term in the search box as shown in the image below:

image showing how to filter for a specific place on AncestryDNA
Image showing how to filter for a specific place on AncestryDNA. Click for a larger image.

And this is what I got:

image showing how to filter for a specific place on AncestryDNA
Click for larger image.

Turns out I have 78 at the moment. I’m sure if I have added the other counties created from Old Ninety-Six, this number would have been much, much higher.  For this exercise, I want to solely concentrate on Edgefield.

Roughly a third of these 78 matches are cousins that I share a common set of 18th Century Quaker x-times-many great grandparents who lived in Pennsylvania. These ancestors didn’t live in Edgefield themselves – but had descendants or extended family members who did. The only reason they appear in the search results above is down to the fact that, like me, they are researching the whole family and not just their own direct line. I already had their ancestors in my tree and they had mine in theirs.

So I’ve placed this group of cousins to one side. For this exercise, I’m solely focussing on cousins whom I know I share a common set of Edgefield-born ancestors.  It’s always a good idea to grapple with a small sample size when dealing with something new; and something as complicated, complex and intricate as genetic inheritance. It’s like learning how a car engine works for the first time. You wouldn’t tackle how the engine works as a whole. You start with how two parts of it relate to one another and work together, and then add a third engine component and a fourth and a fifth until you finally understand how the whole engine works. This is how I’m approaching the Shared Matches tool.

78 people is just far too many to begin to unravel the mystery of this DNA analysis tool.

So I started hunting around within these results for someone who would match me and only a handful of other DNA cousins on the service within these Edgefield results.

The hunt is on for a DNA match who matched me as well as other Edgefield-based DNA matches. Click for larger image
Trial and error: the hunt is on for a DNA match who matched me as well as other Edgefield-based DNA matches. Click for larger image

So I searched around until I found the DNA cousin above. I’ll call her ‘Mary’. 

When I clicked on the ‘Shared Matches’ link on her page, this is what appeared:

Click for larger image
Click for larger image

Mary matches with me as well as 3 other people. Now this is a sample size I can work with when it comes to analyzing the Shared Match tool!

To re-cap, the 5 of us (Mary, myself and the 3 people who share DNA with Mary and I), share ancestors who lived in Edgefield. Which is exactly what I wanted. Now I have to unravel how, exactly, we’re related. Why are there only five of us -and not all of the other people who match me for Edgefield? Why do my known Edgefield cousins (from families like Matthews/Mathis, Holloway, Settles, Williams, Dorn, Ouzts, Peterson, Timmerman, Harlan/Harling, Gilchrist, Borum, etc) match me, but not Mary or the 3 matches she and I have in common. What family line do the five of us share that none of my other Edgefield relations do? Understanding this not only fills in a genealogy information gap. It will give me a sound insight into how the Shared Matches tool works. Only when I understand how this tool really works can I begin to extrapolate and apply what I’ve learned to other groups of shared matches.

I have a feeling that this Shared Match tool is AncestryDNA’s compromise offering for not having a Chromosome Analysis tool like the ones available from Family Tree DNA and Gedmatch.

image A chromosome analsyis i ran on DNA couin match group on Family Tree DNA
A chromosome analysis I ran on DNA cousin match group on Family Tree DNA. Click for larger image.

AncestryDNA’s position on not having a chromosome analysis tool is entrenched. Like many others, I think it’s a bad call.  Knowing the DNA segment lengths you share with DNA matches can provide critical insights. I have nicknames for parts of my chromosomes that I match others on on Gedmatch and FTDNA: names like my Roane segment or my St. Clair segment, my Josey segment or my Matthews/Mathis segment. Or I name them by region: those are my Arab chromosomes or my Central Asian Chromosomes or my Jewish Chromosomes. On FTDNA and Gedmatch, I don’t even have to know the name of person to see how we’re related. More often than not all I need to see is which chromosome segment we match on and share.

While Ancestry’s Segment Match is better than nothing, and will ultimately yield results, it’s not really a substitute for a chromosome anlaytics tool.

With that said, a few things have already piqued my interest with this group of DNA Shared Matches. Mary and two of the other matches have a 100% European ancestry as reported by AncestryDNA. One person has an Ancestry that’s as mixed as mine. Which, initially, tells me that the shared Ancestor pair we have in common is most likely European. And looking at the major ethnicities of Mary and the two other European-descended matches, this common ancestral pair has the highest likelihood of roots in England, Wales, Scotland or Ireland.

And I’m very excited about the guy with an ancestry as mixed as my own, who I will call Joe. Why? Because I know Joe. I know how we’re related on our known white and black Edgefield lines. The common ancestors Joe and I share can’t be shared by Mary and the other 3 people in this shared match result. Which means I can exclude all of the ancestors and relations that Joe and I share in common when it comes to identifying the common ancestral pair that links us to Mary and the 3 others in these results. Somewhere out there is a new white family name I have yet to find. One that Joe and I don’t share with all of our other known Edgefield cousins who have taken the AncestryDNA test to-date.

This is the benefit of working with a small match pool. It narrows the parameters which results in a narrower field of inquiry. And if this is all beginning to sound like a forensic, CSI-esque kind of experience?  Well, it kind of is. Again, it makes my inner-geek happy.

The next step is to dive into the family trees for these matches…if their trees are public. Heck, if they even have them at all. in this case, only one of the trees is private. So I have 3 trees to work with. Which is kind of a lucky break. Trust me, 3 trees to work with was more than I could have hoped for.

The next step will be applying what I will be learning about this tool to other Edgefield family match groups that are larger. And when I have a finely-tuned understanding of this tool? I’ll start applying it to the Irish and Jewish DNA cousins where absolutely nothing is known in terms of ancestors we share in common. That is my end-game.


Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: