Monday, January 31, 2011

Can't see the family for the relatives?

   I have been lost in the world of 23andme and trying to figure out what the astonishing quantity of data I have been given actually means.  I haven't gotten very far...
   23andme is a Genetic Testing service.  With a vial of spit, they can tell you more than you ever thought possible about your health and what conditions you have a greater, typical or decreased risk for based on your genome.  They also give you a report of which conditions you happen to be a carrier even though you may not have that condition yourself.  I really hadn't given much thought to the health information but it is quite interesting.  For example I learned that I am a carrier for hemochromatosis.  I had never heard of it and had to look it up.  But the interesting thing is that it is highly prevalent in people who are Irish or of Irish ancestry.  Fascinating!
   I was a lot more interested in what I could learn to expand my knowledge of my ancestry though.  Through the "Relative Finder" feature the 23andme service sends a report of how many people share matching segments of DNA on their chromosomes.  So far they have determined that I share matching segments with 351 people that have used the service.  That's really neat to know and seems like a lot of cousins...but what do I do with that information? 
   Some of the other participants have Public Profiles, which allow me to see their name and hopefully a list of surnames in their family tree.  So far none of my matches with public profiles have any surnames that seem at all familiar to me.  Others with some common surnames have no segments that match with me.  What to do?
   I have shared trees with some people in hopes that we could discover a common history.  So far that hasn't led to any discoveries of how we could be related.
   From others on the 23andme site, I have learned that there are off-site programs that attempt to process the sheer volume of data and find the connections in ways that go beyond the many features available on the official site.  One such utility is HIRSearch.  From the Facebook page for this site here is what it does:
HIR stands for chromosome Half Identical Region.

HIR Search compares your genome data against another person's genome and find areas where half or more base pairs match. These regions are markers of common ancestry.
After I entered my raw data from 23andme it has given me an easier to contemplate list of people I match and precisely where the match occurs.  Presumably if I find more than one, or several matches at the same spot, then the 3 or more of us should have the same common ancestor.  I think.  So far it has been some fascinating but mind boggling information.

Another offsite utility called merges GEDCOM trees, downloadable from or other family tree software and tries to find common matches.  It also has a function for uploading raw data from 23andme and another genetic testing site and finding not only matches but predicting the degree of relatedness based on those matches.  Since people enter their information voluntarily they can enter their email address and theoretically find it easier to connect with their newly found relatives.  The closest match that I saw of mine was a predicted 4th cousin; many were predicted to be 7th cousins or greater.  The challenge of how to discover the common ancestor shared with so many people is quite daunting; but incredibly compelling at the same time. 

People who have multiple close family members who have also participated in the 23andme process have more information for discovering the connections between themselves and others with whom they have a match.  If Bob Genealogy has a match with Susie Family it is really helpful for him to see if his father Tom Genealogy also matches with Susie at the same location on the same chromosome.  If he does then he knows that their common ancestor must be on his paternal side.  At least they can narrow down their search.  I realize it would be so much more illuminating to have my family members also participate.  I think that will be my next talk them into it!

I haven't had any incredible discoveries yet, beyond the fact that I have 351 new relatives.  But I am just learning what can be done with the information.  All in all it has been incredibly fascinating and I would encourage anyone who was on the fence to give it a try. 

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