Saturday, September 26, 2009
Novel Use of 23andMe Product
By Roberta Estes
With several people considering the purchase of the 23andMe kit during the special promo period when the price is so dramatically reduced, I've had lots of questions about DNA testing in general, about how autosomal testing works, and about possible uses for this test.
I'm going to talk a little about these questions and answers over the next couple of days.
Today I'm going to talk about using this test to prove a relationship.
I can't tell you how many times over the years I've had someone ask me if there as any way to "prove that so and so is my cousin". Of course, the scenario varies with males and females, how closely related, etc., but the basic question is still the same. Before now, I always had to tell them one of three things:
•1. If you are both males and share the surname, you can do the Y dna test which which won't absolutely "prove" it, but is pretty compelling evidence. However this scenario applied to few of the people asking.
•2. If you both descend from a common female through female lines, you can test your mtdna. Most of the time however, the question of paternity was more of the father's identity and did not include a question about the mother.
•3. You can turn to paternity/siblingship testing at a separate nongenealogy lab. These labs attempt to "reconstuct" families using the DNA of the two people in question of course, and hope to get more members of the family (like their parents) to participate as well so that the DNA can be attributed to a source and thereby eliminated or included in the equation. This approach is extremely expensive and often inconclusive.
Let me share my own story.
My father died in a car accident when I was 7 years old. After my step-mother passed away some 25 years later, her daughter sent me a bundle of letters that had to do with my family. One of these letters included a letter from my aunt (my father's sister) to my step-mother. When I first started doing genealogy, some 30+ years ago now, I had called this aunt and asked her many questions. Although she answered them for me, or I thought she had, she apparently was not inclined to divulge what she thought were the family secrets. So she wrote a letter to my step-mother telling her all about how unhappy she was that I was asking "all those nosey questions" and then proceeded to tell my step-mother just what it was she was NOT going to tell me and how it was really none of my business, etc. Well, thank goodness she did that, because several years later, I would get my answers from that very letter. Isn't fate a wonderful thing sometimes.
In the letter was a reference to the fact that my father had another child, a boy. I was utterly stunned. I asked my mother about this and she was very guarded, to say the least, about the topic. I would later learn that it's because the child was born only 5 months before I was born. My father was somewhat of a "colorful character", to put it mildly, and my mother was very embarrassed about the situation. So, apparently, was the other woman, my brother's mother. My father literally had two families in two different states. Talk about the consumate "traveling salesman" story. Anyway, that aside, I began a search for my brother whose name I didn't even know. Talk about a needle in a haystack.
Fast forward about 20 years. I finally found my brother through a combination of dogged research and happy accidents. One of my biggest breaks was when I was trying to apply for a passport and discovered that there had been something filed in a court in Fort Wayne, Indiana having to do with me. I asked my mother why it was filed in Fort Wayne and she told me that was where my father was living at the time. I went to Fort Wayne (to the genealogy library there) for other purposes and subsequently happened by an old City Directory. On a whim I picked it up and found my father, his "wife" and MY BROTHER"S NAME. After that, it wasn't easy, but at least I had names and locations to use. My aunt was long dead by this time and my mother had already told me what she knew, which was little. She knew the first name of the "other woman", but nothing more. At least that much confirmed that I had located the right family.
After searching for nearly 20 years, I finally found my brother a few years ago and he had no idea I existed. He had no siblings and his mother was now deceased as well. We're both glad to have family. He took the Yline DNA test and he did not match the ancestral Estes family. However, that doesn't mean he's not my father's son, because we don't have the DNA of my father. Nor did we have the DNA of my Estes grandfather. My grandfather only had 2 sons who grew to adulthood and had sons that survived past childhood. The one Estes male living in that line took the DNA test, and he didn't match either the Estes ancestral line nor my brother. Now we were really up the creek without a proverbial paddle. I was lucky enough to find one male who descended from my great-grandfather who was still alive and he tested as well, and he does match the Estes ancestral line, so we know that the "break" in the DNA line came either with my grandfather's parentage or his son's parentage or his grandson's parentage.
If you're keeping track here, we have 4 possible locations for the DNA to have been "switched". The names below are fake to protect the guilty:)
My grandfather Will.
My grandfather's first son Joe (my father's brother).
Joe's grandson (who took the test).
My brother (not my father's biological child).
Or a combination of these things.
Here's what I think happened and why.
Joe was the first child born to my grandparents. He arrived 5 months after their marriage. Pure and simple, I think that he was not the child of my grandfather. My grandfather may have known this, or maybe not. I also think that my brother is possibly not my father's child (remember he was gone a lot) as his "other wife" was known to be somewhat promiscuous. But of course there are other scenarios and proof has remained elusive.
How would my brother and I ever unravel this mess? At this point we turned to paternity/siblingship testing. This was extremely expensive, about $1000 for each test. We took this test twice, at two different labs, because the first test came back inconclusive. We match at enough markers to be "suspicious" and at few enough markers for them to declare that we are "probably not half-siblings" but might be related more distantly. Given the geographic circumstances, it's unlikely that we're related at all if we're not half siblings. We were at this point even more exasperated, but we were at the end of what technology had to offer us at the time.
With the introduction of this new test at 23andMe, we will have our answer shortly. 23andMe tests over half a million locations on our DNA, not just the 15 locations that paternity/siblingship testing has to offer. With the Relative Finder product, we'll know for sure if we are half-siblings or not.
How will we feel about this? We've discussed it. Both of us knew our father as our father and he viewed and treated us both as his children. We consider ourselves to be brother and sister and whether that is a function of biology or circumstances is irrelevant in terms of how we view each other. It's no different to us than if one of us were adopted by our parents, we would still be siblings. I am the only family he has (other than his kids) and for me, I have one other half-sibling on my mother's side and that's all I have as well (other than my kids). The world is too small to exclude anyone from the family circle to do with circumstances over which they have no control. But, we do still want to know. He wants to know who his father is and I want to know if I've been doing the wrong genealogy for 30+ years. If I'm not really an Estes biologically (meaning my brother is my biological brother, which means his yline DNA is that of my father and means my father doesn't match the ancestral Estes line), then I'd like to know so I can stop doing the Estes genealogy and move on to whatever family I should be researching.
This has been a long story, but I hope it serves to illustrate how this type of testing can begin to answer questions that were unanswerable before this kind of technology was available.