Gedmatch

I did this when I was trying to figure out if "Bill" was related to me on my BUSCH line. Bill showed up as a match on Ancestry to both myself and my maternal aunt. But all I knew from that was that he matched on my maternal side, not which branch of my maternal line. His tree did show he had a BUSCH line, but it also showed children born after the mother supposed died. I was pretty sure there were errors because his documentation for the facts did not line up. After finding out that he had transferred his DNA to Gedmatch I knew I could explore the match a little deeper.

First I did a "matches both kits" using my kit and my 3rd cousin Joanne's Kit. We know Joanne and I are related on the BUSCH line from our paper trail and by DNA. Bill was one of those that showed up as matching both of us. At this point I knew that Bill was related to me AND that he was related to Joanne. That still didn't prove that we were all related on the BUSCH line although it seemed likely.

My next step was to see where Bill and I shared DNA by doing a one to one comparison.

Then I did a one to one comparison for Joanne and me.

Finally I did a one to one comparison for Joanne and Bill.

The image below shows the results. Note that Bill, Joanne, and I all share common DNA on overlapping segments on Chromosome 6. This plus the paper trails lead to the conclusion that yes we all share the same common ancestor, John Just BUSCH.

Gedmatch does not offer DNA tests, instead it allows you to upload your DNA from any of the three major testing companies to their site. You might wonder why would you want to do that, after all your DNA is already at the company you tested with. There are a few reasons.

First, if you have tested with Ancestry.com you do not have a chromosome browser to be able to see exactly where the shared DNA is located. As you read further on this page you will see the benefit of that option.

Second, if your DNA is ONLY on Ancestry (or Family Tree DNA or 23andMe) you can only compare with those who have tested at that company. By transferring your DNA to Gedmatch you will be able to compare your DNA to those who have also uploaded to Gedmatch from the other companies. This gives you a larger pool of potential cousins to compare with, which will help you find that elusive ancestor (hopefully).

Third, and to me a really big plus, is that Gedmatch is FREE!

One of the tools on Gedmatch is "People who matches one or both of two kits." However you need to remember that just because Person A shares DNA with Person B and that Person C also shares DNA with Person B it does not necessarily mean that Person A and Person C are related as illustrated in the diagram below. To figure our if the three people do share a common ancestor you will need to do a one to one comparison between all three to see if they all share DNA on the same segment(s) on the same chromosome(s).

The bonus? Bill is descended from one of the daughers (Sophie Louise Christine BUSCH) of John Just BUSCH, a line that I didn't know anything about! Joanne descends from Henry Frederick BUSCH and I descend from William Conrad BUSCH. That means of the 9 children of John Just BUSCH we have DNA matches on three of the lines. And that my aunt, Joanne and Bill are all 3rd cousins. Thank you Gedmatch, without your services I would not have been able to figure this out for sure because Bill tested on Ancestry and Joanne tested on 23andMe.