Family History, Adoption, and DNA

When you have a moment, please go over to the blog The Legal Genealogist and read Judy G Russell's article "Blown away with DNA."  This is a moving passage about a person who was adopted and is now using genetic analysis to find relatives.

Several of my genetic matches in the database at 23andMe were adopted.  The only genealogical information they can offer is their own date of birth and location, which does not help when you are looking at connections from the 1700s.  By triangulating and clustering my matches, I can usually provide a possible branch in my documented family tree where the common ancestor could be.  Seeing the names, locations, and dates of possible ancestors means so much to someone who had no family history before taking the DNA test.

I manage two DNA accounts for people with no family history.  One was formally adopted and the other was not.  I do not have results yet for the person who was formally adopted; they are pending through Ancestry.com's new autosomal DNA service.  The results of the person with no official adoption was through 23andMe's Roots into the Future program.  No very close matches were discovered yet, but seeing and exchanging information with distant genetic cousins provides a glimpse into her family's history.

Genetic Triangle

We have a promising genetic cousin match at 23andMe.  We'll call him J.D.  He matches both my father and my father's third cousin, which quite a few people do.  The difference is that the match, or the identical segment of DNA, is the same among J.D., my father, and our third cousin!  Perhaps triangulation describes this scenario?

Here is what the graph looks like:

The common ancestors shared by my father and his third cousin are their great great grandparents, Calvin Cook and Mary Neil.  They were born around 1830 and lived in Morris and Hudson Counties in New Jersey.  We do not know at this point if the shared DNA on chromosome 13 is from Cook or Neil.  We need to go back in time in both trees and we should find an ancestor in common with J.D.  We do not know how many generations back we must explore until we find a common ancestor.  All we know right now is that the match is through Calvin Cook's line or Mary Neil's line, which greatly narrows our search.

This illustrates why you need document-based genealogical research to help you with DNA genealogy.

Compare the above graph to this graph.  A. D. matches both my father and his third cousin, but on different chromosomes.  We cannot determine with this information if the double matching indicates a single common ancestor.

New Genealogy Features at 23andMe

23andMe has launched some new features to assist in figuring out how it is that your matches match you.  You can type in your family tree.  This is a Beta version and is not cooperating with me for dates and locations.  I do not know if this will be a handy reference for your matches or if the site will somehow propose possible connections based on the comparisons of the trees.

You have always been able to list surnames in your profile.  Many a match has written to me that we can't be related because they don't recognize any surnames in my profile, and then cut off contact.  This is rather silly, especially when the person has only researched one or two generations of their own tree.  If everyone knew every ancestral surname on every line for the past 500 years, then genealogical research and DNA studies would not need to exist.

The next feature is a map with locations of your genetic cousins marked in purple.

23andMe
Map of matches of my father

23andMe
Map of matches of my mother

Compare the maps of my father versus my mother.  My mother has more matches, which we knew, but with a clear concentration in Eastern Europe that my father does not have.  The numbers represent how many people claim such a location, so the hidden numbers could be 1 or 20.  You have to zoom in to see.

23andMe
Locations in the United States of my mother's closest matches

Manipulation of the degree of cousinship brought me to the New York area, the only location of my mother's closest cousins in the United States.  You can click on the little purple flag to reveal the relation and surprise!  All of these locations are for the same cousin.  The locations are any places mentioned in the profile, instead of a birthplace, which would have been more useful.

So onward to the next new feature:  shared surnames among the matches.

23andMe
Shared surnames among genetic matches for my mother

I was not surprised to see Cohen as the most frequent surname among my mother's matches.  As with the place maps, the common surnames are not the name of the match, but rather any surname mentioned in the profile.  I am not sure what the enrichment value means.  I figure it is some measure of the degree of commonality of a surname in general.

23andMe
Shared surnames among genetic matches of my maternal uncle

My mother's brother's matches revealed the Irish surnames.  The problem that I am having with these Irish names is that they are so common anyway.  Most of the Irish matches have at least one ancestral surname in common with us.

I turned to my father's common surname list next, putting my extensive research to the test.

23andMe
Shared surnames among genetic matches of my father

I have Marsh and Strong in my paternal ancestral lines.  I have been seeing a lot of Adam.  Hall and Hickman are interesting because I am working on a possible Hale and Hickman connection from the Strong line.

These new genealogy tools will be useful and are a welcome addition at 23andMe.