Sunday, June 6, 2010

DNA Results - The Long Version

Let me first state that I do not feel that our genes or DNA connections are of any significance. The only reason I work on family history is because I enjoy it, and I certainly hope others will do the same. I love all of my current family. The relationships I have with cousins, nieces, nephews, siblings, or any 'in-laws' are all SOOOOOO importance to me, whether we share DNA or not!

The reason DNA testing is important is that it can scientifically verify whether the 'paper trail' we have found is correct or not.

We now have proof that goes back three centuries. Hans Heinrich Hoffman's 300th birthday will be in 2012, and Ebenezer Norton's 300th birthday will be in 2015. We have DNA confirmatiion that these men and their wives were our g,g...grandparents.

We do not have any DNA from these folks, so how does this DNA thing work? Here is my best effort at an explanation:

Most of human DNA gets all mixed up because we get half from our mother and half from our father. But the copies of the Y-chromasomes are passed down with no changes from father to son, although rare mutations do happen. Because this Y-chromasome does not change much, men who share the same male ancestors also share exact copies of his Y-chromasome. My Y-chromasome is the same as Joe Hoffman, is the same as Harold Wayne Hoffman, is the same as the father of Sylvester Hoffman, is the same as the g-g-g-grandfather of Sylvester, etc.

If we can find a very distant cousin who descends from a known common ancestor, we can verify this relationship with DNA testing.

This is exactly what we've done in both the Norton and Hoffman families.

For our Hoffman family, there is a man named Lee Hoffman, who lives in Montgomery County, Kentucky. He has traced his ancestry to the same family as we have (Hans Heinrich and Margaret [Huettenhen] Hoffman). After DNA testing, he and I ended up with a 36/37 match for our Y-DNA. The odds of this happening are difficult to calculate, but they are astronomical. Imagine two people, each sitting down with dice and rolling matching numbers 36 out of 37 times. In the case of our DNA, the laboratory measures 37 different locations on the Y-chromasome. One of the 37 markers obviously had a minor mutation. In fact, the one marker that mutated in this case, is a spot that has a fairly high mutation rate. So when considering the 15 generations that separate Lee and I, it might be expected to have at least one marker off by one. (From me to Hans Heinrich is 8 generations, and from Hans Heinrich down to Lee is 7 generations).

Since I know a little bit about laboratory testing, I was actually somewhat suspicious of how accurate these results would be. After looking into it, I can confidently say that it is amazingly precise. It is much like counting the links of a short chain, between about 10 and 25 links at each 'location' along the Y-chromasome. The way that these links are 'counted' is as nearly perfect as any testing can be.

Because the Y-chromasome is passed down through men, only men can participate in Y-DNA testing. But women can benefit from the knowledge. Ruth's brother Dan was just recently notified of his results. Our reasearch showed that our Nortons descend from a family in Guilford, Connecticut in the late 1600s. Two other descendants of this family have had DNA testing, so we hoped for a match. Dan matched one man 23/25 and the other man 35/37. These matches are not perfect, but are very, very good. The coordinater of the Norton DNA Project immediately knew which family we came from, even before we told him!

In the left hand column of this blog, I will link to the two DNA projects mentioned above. I would love to get a DNA verification of other branches of our family. I know there are Stout men and Bagley men who could contribute to this. If anyone knows of someone who would be willing to participate, please let me know. It is a very simple thing. You just rub the inside of your cheek with a swab they send you in the mail, and send it back to them. Then wait to see if you hit the lottery numbers right or not! There is a cost, but if you are interested it is well worth it.

Like all forms of 'evidence', there are some problems with DNA testing, I will cover these in the next post.

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