Wednesday, June 13, 2012

DNA Tutorial for Genealogy

I came across terrific online explanations of DNA from the University of Utah.  The short videos plainly explain four types of genetic inheritance:  autosomal, X chromosome, Y chromosome, and mitochondrial DNA, and their applicability to genealogical research.

The testing that I write about from 23andMe is autosomal.  The kit that I ordered from Ancestry a few days ago is autosomal testing.  The surname projects at FamilyTreeDNA (which I have not done yet) are Y chromosome DNA testing.

2 comments:

  1. Hi Jody,

    nice series of articles about DNA testing. I'm interested in doing the same testing myself but haven't quite pulled the trigger yet. I've probably missed it in the blog entries but can you share what led you to pick Ancestry.com for your DNA testing? I'm curious if there are other DNA testing services that you would recommend.

    thanks.

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  2. For my first round of DNA testing, I chose Ancestry.com because I use the site daily and figured that they would be best positioned to combine DNA testing with genealogy. As detailed here, the results were disappointing in that only the Y-DNA and mtDNA was tested and the results were confusing with no hope of identifying who, if anybody, actually was a match.
    The next round was autosomal DNA testing at 23andMe during a sale. My results triggered the need/interest in testing additional family members. Having everybody’s results in one spot makes comparisons easier. I also uploaded these results to FamilyTreeDNA when they offered a sale on transfers.
    I have an autosomal kit pending at Ancestry.com, so I can’t comment yet on how Ancestry’s new DNA testing works out. Again, this kit was acquired through an introductory sale. I am reading good things about the results that Ancestry produces, including side-by-side comparison of family trees with suggestions regarding the common ancestor. The specimen I used is from someone who is adopted, so I have no family tree to post for this person, so I may miss out on this aspect.
    The database size at23andMe appears to be several times larger than FamilyTreeDNA. This is not necessarily useful. Most matches at 23andMe are anonymous and do not respond to inquiries. This is very frustrating. Both companies need to employ the comparison utilities used at the free site GedMatch.com. Until then, I am using manual data entry methods to compare and categorize the matches at both sites. I do not know about the ability to compare matches at Ancestry yet.
    I’d like to see how Ancestry’s autosomal DNA services work out before I decide which site I like best.

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