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Durham DNA – 10 Things I Learned Despite No Y DNA Matches, 52 Ancestors #167

First and foremost, I want to thank my Durham cousin for stepping up and taking both the Y DNA and Family Finder tests to represent the Thomas Durham Sr. line of Richmond County, Virginia.

My cousin descends from Thomas Durham Jr., son of Thomas Durham Sr. and wife, Dorothy. Thomas Durham Sr.’s parents are unknown, which is part of why we needed a Durham male to take the Y DNA test.

What Might a Y DNA Test Tell Us?

A Y DNA test would tell us if our Durham line matches any other male Durham who had tested. In addition, if we were be lucky enough to find a match to a Durham who knew their ancestor’s location in the UK, where we presume our Durham family originated, we would have significant clues as to where to look for early records of our line.

What Did the Y DNA Test Tell Us?

The Y DNA test told us that our Durham cousin matches exactly no one, at any level, on his Y DNA test.

What, you might be asking? Is that even possible?

Yes, it is. I write the Personalized DNA Reports for customers, and I do still see people with absolutely no matches from time to time. When I drop their DNA results into a frequency chart and look at the percentage of people with their values in their haplogroup at each location, it’s usually immediately obvious why they have no matches. They have several mutations that are quite rare and those, cumulatively, keep them from matching others. In order to be considered at match, you must match other individuals at a minimum number of markers at each panel level, meaning 23, 15, 37, 67 and 111.

Now, this isn’t all bad news. It’s actually good news – because with rare markers, it’s very unlikely that you’re going to match a group of men by chance or just because your ancestor hundreds or thousands of years ago was very successfully prolific. I see some men in haplogroup R that have hundreds and thousands of matches, especially at 12 and 25 markers, so while no match is frustrating, it’s not a disaster because one day, our Durham line WILL have a match and it will be relevant.

The Durham Project

Being a curious skeptic, I visited the Durham DNA project and checked to be sure that my cousin’s DNA really didn’t match anyone, even distantly. I wanted to be sure that my cousins’ results weren’t “just one” marker difference in terms of allowable genetic distance to be considered a match.

Please note that you can click on any graphic to enlarge.

My Durham cousin’s haplogroup is I-M223.

There are no other people in the I-M223 Durham group. Checking my cousin’s markers, they are quite distant as well, so no Durham matches, even at a distance.

Now, here’s some good news.

Looking at the project’s Patriarch’s page, we can see which lines we don’t match.

We don’t match any of these lines, including the two that are from England. Two lines down, several to go.

Autosomal DNA

About this time, I began to have this nagging thought. What if my cousin’s Durham line isn’t really the right Durham line? What if the genealogy was wrong? What if the genealogy was right, but there was an adoption someplace in the 9 generations between Thomas Durham Sr. and my cousin? Those “what-ifs” will kill you, being a genetic genealogist.

So, I decided to see if my cousin’s autosomal results matched any of those known to be descended from the Durham-Dodson line. Thomas Durham Sr.’s daughter, Mary Durham, married Thomas Dodson. This line was prolific, having many children, so surely, if my Durham cousin descends from Thomas Durham’s son, Thomas Jr., some of the Dodson/Durham descendants from Thomas Durham Sr.’s other child, Mary, will match him, hopefully on a common segment.

Perusing my Durham cousin’s Family Finder DNA matches, and searching by Dodson, I found 27 matches.

I checked the Ancestry Surnames of those matches, and yes, 5 included both Dodson and Durham.

Checking pedigree charts, I verified that indeed, these people descended from the same Dodson/Durham lineage.

Thankfully, 4 of 5 matches had pedigree charts uploaded.

I selected those 5 people and viewed their results in a chromosome browser, compared to my Durham cousin.

As you can see, there are two sets of results where more than one person matches my Durham cousin on the same segment.

On chromosome 9, the green and orange person match the Durham cousin on segments of 12.36 cM

On chromosome 21, the pink and yellow person match my Durham cousin with a segment of 8.83 cM.

Now, as we know, just because two people match someone on the same segment does NOT automatically means that they match each other. They could be matching you on different sides of your DNA – one on your mother’s side and one on your father’s side

Next, I utilized the matrix tool to see if these individuals also match each other.

This matrix shows exactly what we would expect.

The bottom person, Gwen, matches the Durham cousin on chromosome 1 and doesn’t match any of the other cousins on that segment. The matrix tells us that Gwen doesn’t match either of these other two cousins either.

The matrix tells us that both kits managed by Ted match each other. This could be one person who uploaded two kits, but the photos are different. These two kits are the chromosome 9 match.

Then, the matrix tells us that Odis and Diana match each other, and sure enough, those are our chromosome 21 matches.

While this alone does not prove triangulation, because we can’t confirm that indeed, Gwen and Odis do match each other on this segment, at least not without asking them, my experience suggests that it would be a rare occasion indeed if this was not a triangulated match – indicating a common ancestor.

Triangulated matches minimally require:

We Can Do More

We aren’t done yet. Next we can look to see which of these matches might ALSO match someone else in common with our Durham cousin.

Take each match, one at a time, and do an In Common With (ICW) search with them. You can read about the various options for in common with searching in the article, Increasing “In Common With” (ICW) Functionality at Family Tree DNA.

First, I just searched in common with the Durham surname, and none of these folks matched anyone else on the Durham surname match list.

To do this, search for Durham, select a match, then click on ICW, leaving Durham in the search box.

Second, I searched by selecting the match by checking the little checkbox by their name, but removed Durham from the search box so that I could see if my Durham cousin matched this person in common with anyone else on his match list, regardless of their ancestral surname.

As you would expect, many of the people returned on the ICW match list don’t have ancestral surnames listed.

When you have a few people to compare, the chromosome browser is wonderful, but for a lot of comparisons, there’s an easier way.

If I were my Durham cousin, I’d download my full list of matches with chromosome segments and see who matches me on those Durham/Dodson segments on chromosomes 9 and 21.  I would then look to see if they have pedigree charts uploaded, or contact them asking about genealogy.

You can download all of your match results at the top of your chromosome browser by clicking “download all matches.”

This enables you to sort the resulting spreadsheet by segment number and chromosome. You can read more about that in the article, Concepts – Sorting Spreadsheets for Autosomal DNA.

Of course, that’s how genetic genealogy addicts are born. You’re never really done.

What Did We Learn?

What did we learn, even though we had no Y matches, and are understandably disappointed.

Not All is Lost

I know it’s initially very discouraging to see that someone has no Y matches, but truly, all is not lost.

Not only is all not lost, we’ve learned a great deal. Y DNA testing in conjunction with autosomal is an extremely powerful tool.

Not to mention that our Durham cousin’s Y DNA results are now out their fishing, 24X7, 365 days per year, just waiting for that Durham man from some small village in the UK to test – and match. Yep, that’s my dream and I know, I just know, it will happen one day.

Thank you again, to my Durham cousin. When men Y DNA test, they not only serve their own interests, but those of others who descend from the same ancestral surname line.

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