Friday, August 03, 2012

So...Why a second DNA test when the first one failed?

I'm still waiting for the results of my great big genealogy gamble (follow-up posts here and here). No one has asked why I gambled on this second (autosomal DNA) test when the first (yDNA) test failed, but I'll explain, anyway.

For yDNA, you have to compare direct male descendants. If you can't read the scribbled chart that I used to help me think, here are the highlights:
  • Henry and Isaac Maness were brothers, sons of Abednego (possibly a triplet).
  • Henry's son Thomas Swain Maness (blue arrow - my suspected great-great grandfather) and Isaac's son Tommy were first cousins.
  • We compared yDNA between Tommy's grandson (Mr. Thurman) and my uncle. If Swain is our ancestor, they would be third cousins, once removed, and both direct male descendants.
They didn't match. In fact, we didn't seem to be even remotely related!

Here's why I didn't give up: 
  • The similarities are uncanny. Same name, same age, from the same county. Swain was rumoured to have several wives, including one in Randolph County. Both men were woodcutters by trade. Both were dark-haired or "black-headed" men.
  •  Most of this genealogical information is from oral history — it seems reliable because it's only second hand. Mr. Thurman lived to be 101, and his father told him this information! However, we have no primary sources for Swain's birth or family.
Swain was orphaned as a boy and reared by relatives. Was he really part of the Maness family? I looked at other DNA results in the Maness family project (a great resource, found through Family Tree DNA - aff link). I drew a blue line on my chart to show that Mr. Thurman matched a descendant of Seth, Abednego's brother. That confirms that Mr. Thurman was indeed part of the Maness family. No one in Henry's line, however, has been tested. There are several places in the family tree where a "biological incident" could have occurred (aka an illegitimate child). The best way to check would be to test one of Swain's descendants. But the only ones I've found, so far, are female.

In the past year, autosomal testing (Family Finder test) has taken off and I learned that we could now test one of Swain's granddaughters. The comparison is supposed to be reliable up to third cousins. If Swain is our ancestor, my uncle and Ms. Lessie would be first cousins, once removed.

New technology is opening up doors to genealogy that didn't exist when I started this blog, much less two decades ago when I started searching for Thomas S. Maness!

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