google-site-verification: google1a99cbc777ffb68f.html

DNA - Where do I test? (Part I)


   I’ve had some questions this week about where to test.  Way back in February when I wrote about Creating a Research Plan I emphasized the importance of starting with a question. It’s no different with DNA.

   Why do you want to test?

   What is the problem you are trying to solve?

   On of the things I hear constantly is that people are overwhelmed by their results.  The next comment relates to their matches who do not have a tree, or really any information about their ancestry, and when you contact them, they don’t respond.  Think about the advertisements you see on TV for DNA testing…what do they promote?  They focus on ethnicity.  I thought I was Scottish and but my DNA test told me that I was German.  Many of these people have never considered doing genealogical research and probably don’t know much about their family. As genealogists we do know something about our family, and the ethnicity results can sometimes be frustrating.  To quote Judy Russell, the Legal Genealogist, the ethnicity estimates just “just aren’t soup.”  However, as genealogists, we’re more interested in the cousin matches.  

   I spent years trying to figure out why I should test, and once I did, what to do with the results.  I first tested in 2009 with 23&Me and I did it for medical reasons, not genealogy, but I did get a list of matches, none of whom I recognized.  23&Me has gone through some major changes since I tested, and the medical results I got (which were extensive and pretty accurate) are not all available under their current program.  They stopped the medical portion of their testing as they worked with the FDA to get approvals.  Some of the results are now available again. Since I’m going to be discussing health history in the next few weeks I’ll put off the health discussion for now. (Thanksgiving Day has been designated as Family Health History Day by the Surgeon General since 2004.) 

   You need to begin by defining the problem you are trying to resolve and creating your question.  My question (identified two weeks ago) was: Are Brian Moughty and Jack Moughty related?  Both are males with the same surname, so a Y-DNA test would likely answer that question.  Only males carry the Y chromosome and it is passed with very little change from father to son.  So it should show if Brian and Jack share a common ancestor.   If you are trying to solve a male descendant issue within a specific surname, or possibly an adoption issue for a male,  you’ll want to look at Y-DNA testing, and you have one choice; FamilyTree DNA.  Although there is only one company, there is still a choice to determine how many markers to test.

   If your problem relates to your female line, then mtDNA (mitochondrial DNA) would be the appropriate test and again, it is only available through FamilyTree DNA.

   In the case of both of these tests, you’re not likely to just take the test and see what’s out there.  Brian and Jack, for example are the only two matches on their Y-DNA with a distance of 0 or 1 (number of mutations) and they are the only Moughtys.  If only Brian had tested I’d still be sitting here waiting for some kind of a match.  Now if you have a very common surname, you may have the opposite problem of too many matches.  

   That’s the case with my mtDNA.  I wasn’t particularly trying to solve a problem, but trying to learn about mtDNA.  It’s an expensive test, but I decided to go for the full sequence matching.  My haplogroup is H1 (the most common).  I’ve got over 300 matches but up until this weekend they were all at a genetic distance of 1 which would likely have been more than 500 years ago.  That’s not going to solve a problem.  This weekend I got my first match with a genetic distance of 0.  That could still likely be outside of existing my genealogical records (especially with the Irish).  According to FamilyTree DNA, a perfect match (genetic distance of 0) has only a 50% chance of being within the past 5 generations and a 95% chance of being within 22 generations (about 550 years).  But like Y-DNA, if you have a specific problem, trying to prove that a specific woman is related in your mother’s line and you can find a descendant, this test might be the answer.  Here’s a link to an article by Debbie Parker Wayne (co-author of Genetic Genealogy in Practice) that explains mtDNA patterns.  One thing to remember is that mothers pass their mtDNA to both sons and daughters, however, only daughters can pass it on.  If you identify a male descendant on a matriarchal line, you may be able to test him.  

   Well, if Y-DNA addresses the direct paternal line and mtDNA addresses the direct female line what about everyone in the middle?  That’s where atDNA or autosomal DNA comes in.  Here your choices get considerably more broad.  Next week, I’ll address the companies providing atDNA testing.

   Happy Hunting!  


 FindMy Past Offer Ends tomorrow!

   

© Donna M. Moughty 2007- 2017