Using Gedmatch "one to many"

For autosomal DNA matching, Gedmatch offers a feature which allows you to see where your autosomal DNA matches others who upload their results. Gedmatch takes uploads from ancestry.com, FTDNA, and from 23andme, so even if you only test with one company, as many do, you can see many matches to your DNA segments from people who tested with the other companies.

It is very easy to use this feature, and it is worth checking back every few weeks for the new matches which are uploaded. The moniker and email for the match are sometimes helpful, yet ofttimes not helpful at all--really attempts by the test subject to obfuscate his or her identity. The best scenario, and it is occurring more and more often, is that the match has uploaded a gedcom, which is worth way more than a name. After all, we researchers are looking for the match's grandparents and beyond. It is genetic history that is of interest in this game.

If a match seems useful, ways to look further are to check the match's list of matches (click on "L"). The individual that you match may not list his or her name, but may have a match within one or two generations who has done so. That is quite valuable, and worth working with to find clues to creating the tree for the match (an important step in finding the common ancestor). Another step is to find the chromosome segment where you match, and then to find the others who match (triangulation), which is another feature on gedmatch, and discussed elsewhere on this blog.

You will probably also want to click on A, which shows you the chromosome segment where you match the other tester. You can make a note of this segment and then check for matches elsewhere on gedmatch or on HIRsearch to that particular segment. Because the segment match may be on either side of your ancestry (paternal or maternal), the fact that it matches a third party may not reflect a true match. It could be coincidental, and the match may be to  the parent who would not match the second party and yourself. This is where triangulation is of great help, because gedmatch will show you where your matching segments of chromosome overlap with more than one other match, and the information on the utility will even indicate for you that this is likely an indication of shared ancestry.

Now what can you do with shared ancestry? Ideally the people you match with have more information on their ancestry than you do, and you can see who might be the common ancestor, or at least the direction that the ancestry will have to be. Less ideally, you may have more information to work with. Geography, names, anything can be helpful. You should note all of the information you receive (a good place to do it is on a digital family tree--easily revised) so that it can come in handy when you get more information, which is likely to happen given the recent surge in autosomal testing.

Don't forget that if you get intrigued by a chromosome segment that you can easily see matches who also share that segment by uploading your data to HIRsearch.

The gedmatch.com site has many features. It may take awhile to tackle all of them. I do recommend trying this one, and taking the time to figure it out. It is one you are likely to return to and to find useful as you try to establish your genetic ancestry, which, as we all know, may just not quite match the family history you have on paper.

Gedmatch no longer down! (updated March 24)

Update March 24: Gedmatch is up and running again!

Yes, just as we got used to gedmatch.com being there and adding new features right and left, we were met with the recurring server failure notice. It is unexpected even though it happens often, and what a blow it is at this time. The new features were making chromosome segment comparison easy and fun, and changes were almost moving too fast. As before, my advice is to be patient, just as we are with receiving matches from the companies we are subscribed to, and once gedmatch is up and running again, just be sure to take advantage of the features there for your most interesting genealogical problems. For those who have been in this for awhile, finding matches, using utilities, and so on, you know that it has been a very up and down process with many long detours and stops along the way. If you are new to all of this, be glad of the many options we have. And while you are waiting, be sure to check out HIRsearch and promethease--both interesting and fun to use.

With all of the options out there, those who are working hard at finding common ancestors should be finding at least a few previously unknown ancestors out there. Let me know if you have done so or if you are narrowing down those names and places!

HIR search

A very simple website for comparing autosomal DNA results against those of many other individuals is Leon Kull's HIRsearch. You submit your data from the testing company, and you are welcome to use a pseudonym. You can compare your results on any chromosome or you can see overall the names of your best matches, and to what degree there is a match.
Strangely, the website seems to be falling off of the general radar for search engines, yet can still be accessed through links on other websites.

See http://hirs.snpology.com/

Update December 2011: HirSearch is once again easily found with search engines. Thank goodness!

DNA fits very well into the rhythms of the ancestor search

I am having so much fun looking at  DNA matching that I have to write about it again. DNA testing fits so well into the genealogy search.

I knew it would be interesting to get some DNA results when I first did the testing. But my fear was that the results would lose their novelty. That is where I had such a pleasant surprise. The testing works incredibly well as an interactive process, and the potential for that type of searching is only going to increase.

Especially with autosomal DNA tests, you can look at gedcoms of matches, and work on matching the paper trail. You can check back against the chromosome matches. The more matches you have who overlap in one area, the  more chances of finding a common ancestor there. It is just fascinating, and  when you run into dead ends, new matches come along (well, honestly, not usually quite that punctually, but still, often enough). You can contact your matches and collaborate with them if they are so inclined.

Gedmatch.com, which is free, offers wonderful options for looking at all your chromosome matches visually, to see where there are overlaps (chromosome browser) and the triangulation utility can show you who matches your matches (a great feature, especially for the non-communicative matches). And then there is the comparing on HIRSearch and its companion page on facebook, and then there are all the Y-DNA projects to check out as well. Finding distant cousins is not easy with this method, but it does work, and is extremely rewarding.

I have already identified the common ancestors of several of my distant cousins (as identified by the testing company), and look forward to the fun of tracking down more.