An Update on Steve: Clarke and McMaster/MacMaster DNA & Genealogy

I recently wrote a Blog on McMaster DNA and Genealogy based on a newly tested McMaster descendant named Keith. In that Blog, I was running into issues due to McMaster descendants testing at different companies. Steve had tested at 23andme which is a good company, but their newer DNA test was not compatible with Gedmatch or MyHeritage. Since I wrote the Blog, MyHeritage figured out a way to integrate 23andme results into their program.

Steve’s Genealogy

It took me a little while to figure out that Steve and his closer relatives were related to me more closely on the Clarke line than the McMaster Line.

Here on the Clarke side, Steve and I are 3rd cousins, once removed.

On the McMaster or MacMaster side as Ron and Steve prefer, we are 5th cousins.

That is a huge difference from a DNA point of view. Here are the reported differences:

On average, I may expect a 25 cM match on the McMaster but twice as much on the Clarke Line.

Steve’s DNA

From the above chart, I might expect a match with Steve of about 73 cM. That would be an average reported amount of 48 cM on the Clarke side and 25 cM on the McMaster side. MyHeritage shows that Steve and I have a shared match with Emily:

Emily is related to me on the McMaster side, but not the Clarke side. She is also related to me on the Frazer side where Steve is not related. The above image shows that I match Steve at 49.4 cM. That amount could be all Clarke DNA  or much less likely all McMaster or part Clarke and part McMaster DNA.  I match Emily at 69.1 cM. She is my 2nd cousin once removed on my McMaster/Frazer side. Steve matches Emily’s DNA on their McMaster only side at 23.9 cM. Steve and Emily are 4th cousins once removed.

I hope that made sense. The point is, that when you are related to someone by DNA on two different lines, it is good to have someone to compare to who is only related on one of those lines to sort things out.

Steve and Triangulation Groups at MyHeritage

According to MyHeritage:

Triangulated segments are shared DNA segments that you (or a person whose DNA kit you manage) and all of the selected DNA Matches share with each other, and therefore likely all inherited from a common ancestor.

Steve, Emily and I above did not show triangulated segments, but Ron, Steve and I do:

I circled the icon that indicates that Ron, Steve and I are in a Triangulation Group (TG). Here is how it looks on a chromosome browser:

The red is me and Steve. The yellow is my match with Ron. Where they all overlap is the triangulation group. In order for this to work, Steve and Ron must match each other. Where they overlap is 9.3 cM.

This is my interpretation of what the TG indicates. I can’t prove this unless I have someone else who has Clarke only ancestors in the TG. However, this scenario is much more likely compared to the further out McMaster relationship. The TG at Chromosome 18 is a similar scenario.

Another of Steve’s TGs Confirmed – McMaster DNA

In a previous Blog highlighting Steve, I hypothesized that Steve was in a TG with my sister Lori, Ron, and Emily. Emily has no known Clarke ancestry, so that would mean that the TG on Chromosome 13 would represent McMaster DNA. Here is what MyHeritage now shows:

Lori matches Ron, Emily and Steve at the same place. MyHeritage has the match highlighted as triangulated segments.

So even, though DNA matches between Lori and Steve are more likely to be Clarke matches, this DNA match has to be a McMaster match.

Finding Other Clarke Relatives

I’d like to find more Clarke relatives as that is where I am stuck on the genealogy. Here is my grandmother’s tree:

Ron and Steve are related to my grandmother on her paternal McMaster side on the top of the tree above. They are also more closely related on her maternal Clarke/Spratt side on the bottom half of the chart. That is where I have more blanks.

Shared Matches at AncestryDNA

I went to AncestryDNA and found shared matches with Ron. He is my closest relative on my Clarke tree.

I had built a similar chart in my previous Blog on McMaster DNA. The yellow match was also a common match to Keith who had McMaster ancestry but no known Clarke ancestry. My guess is that the non-yellow shared matches should have Clarke or Spratt ancestry. Some of these people have trees, so it would be a good idea to look at them. However, my guess is that these people would have the same difficulties in finding their ancestors as I did. Instead, I’ll try something different.

AncestryDNA Circle with New Ancestor Discovery Long

Ancestry has me in a circle with others such that Ancestry thinks I may have a New Ancestor Discovery (NAD) with someone named Seymore Long.

Perhaps I can back into this Long Family through my Irish side. That is where I have some brick walls. Here is some further information Ancestry has on Seymore:

So perhaps the Long family made their way over from England or Ireland and that somehow I’m related.

Summary and Conclusions

  • Now that Steve has been incorporated into the MyHeritage results, it is easier to do DNA comparisons on him.
  • My assumption is that my AncestryDNA Shared Matches with Steve, Ron and others from that branch will be twice as likely to be Clarke relatives compared to McMaster or MacMaster relatives.
  • I gave an example of one McMaster relative based on DNA triangulation.
  • It is difficult to prove Clarke only relatives. This is because I have not found a Clarke descendant that does not have McMaster relatives. Also I have not yet found a genealogical tree to further the work I have done on the Clarke Line.


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