Genetic Genealogy - who was my great grandfather?

During the Black Friday sales last December, I bought two Ancestry kits. I actually mean't to order one, but made a bit of a mess of it. Still, I thought, they were as cheap as I've seen a DNA kit, so I let the order process.

Some people might exclaim - but you've tested your DNA to death!  These kits were not directly intend for myself though.  I intended them for the art of Genetic Genealogy.  To help me verify my paper tree, biologically.

Although I enjoy the kick that I get from matching segments of DNA in strangers, to shared ancestors of the past on all lines, I'm particularly interested in one line, from one great grandfather.  You see, I had a very naughty great grandmother.  I have uncovered evidence of two bigamous marriages by her, as well as other relationships.  A second cousin of mine, through her, doesn't appear to have the amount of shared DNA that I would expect for a full second cousin.  It looks worse than even the old family rumours.

As I do have an extensive family tree down to that birth certificated great grandfather, even though I know full well that biological family isn't always as good family as non-biological, which the paper trail honours, I'd still like to know.  With Genetic Genealogy, I hope to verify - or otherwise, his biological relationship.

So... I used one kit to test one of my siblings, and the other to test my mother.  I've tested my mother before on 23andme.  Mistake.  I've learned a lot about DNA testing over the past few years or so.  Ancestry.com might seem like a heavy marketing, greedy big DNA company, with some slightly dishonest sales ploys (find out if your ancestor was a Viking!), and pressure to subscribe to more services in order to get the full benefit of the test - BUT ... it 1) has an awesome family tree building website for subscribers, that link to DNA tests, 2) has the largest customer database, and 3) through it's genealogy services, as well as marketing, has the most UK testers in it's database.

Okay, it's a little dumbed down.  The messaging system sucks (so I always send my email address), It doesn't provide a chromosome browser.  It doesn't provide segment locations on chromosomes.  But - for my uses - using DNA matches to verify a family tree pedigree, it serves extremely well.  I have had almost ten times more matches on AncestryDNA, than from 23andme, FT-DNA, and GEDmatch combined.  And many have online trees!

I've received my siblings results.  Wow.  I suspected it.  That the sibling has inherited some quite different DNA from the parents mean't that although we share some DNA matches, there are many that we don't!  Up to now, I've just used a spreadsheet to keep results of verified matches.  I could see that I now need something more powerful.  Something that I could search on - and filter different lineages.  When my mother's results arrived, I'll be able to divide all of my matches into maternal, or paternal sides.  On top of that, I have a 1C1R (first cousin once removed) on my father's side, that I can sometimes use to indicate some ancestry on his side.  I can look at all of my matches and their shared matches, and triangulate, where abouts they fit into my family tree.  I built a personal database for my DNA matches.

So I'm pretty pleased that I invested in those two kits during the sales.  It's kept me busy.

I used Open Office Base to build the database:

Okay it's basic and not pretty, but I can extend on it.  I've imputed our closest 187 DNA matches, nearly all from Ancestry, plus a few verified from FT-DNA and GEDMATCH.  It's a family match - I've included forms for imputing my mother's and sibling's matching segments - not just my own.  Any genuine matches that my sibling has - are also my cousins.  Just that I don't have personally share DNA segments with them.  I've also included a yes/no check box for that 1C1R.

I've used it to query an up-to-date list of "our" shared DNA matches that share a correlating common ancestor or two on their trees with ours.  My biological "verifiers".

Using the open source GRAMPS app, I produced a fresh family pedigree fan chart.  I then used open source GIMP to colour in the ancestors that I have verified with shared DNA segments.  The darker the tone, the more matches:

It's generally looking pretty verified isn't it.  My birth certificate grandparents were all very clearly, my biological grandparents.  The great grandparents, and the majority of great great grandparents are also looking pretty verified.  But what about that great grandfather?  The birth certificate version was my surname great grandparent, and biological version was my Y-DNA great grandparent.  Were they the same?

Well I still do not have evidence that I'd regard as overwhelming.  But I am gathering evidence that he may have been the same guy.  I have two DNA matches that strike directly through him.  Unfortunately, both were distant ancestry, with only a small shared segment each (around 7 cM).  That small, they could either belong to an undocumented relationship elsewhere, or even be identical but not by descent.  But it's evidence that I'm building, and it's more reassuring than if he'd had no DNA matches strike through his lineage to us.  The other supportive evidence was that my biological paternal line great grandfather carried an incredibly rare haplogroup: Y haplogroup L-SK1414 (L1b2c).  The only other L-SK1414 so far found in the British Isles, traced his paternal surname line back to Basingstoke, around 1740.  My documented surname line traces back in 1740 to Long Wittenham, Berkshire.  Only about 32 miles away from the Basingstoke L-SK1414 by road.  Could be a coincidence, but it supports that the Y-DNA could still correspond with the surname line back in 1740, and that my great grandaddy, was my DNA great grandaddy.

Such is the power of genetic genealogy.  Roll on the results of my mother.  That will reduce the number of matches that are likely to be on my paternal side.

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