Re: Inferences from marker comparisons #dna
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awestreich@...
The approach I have seen to compare markers within a group of (possible)
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cousins is to: (1) calculate a "modal haplotype" which approximates the haplotype of the Most Recent Common Ancestor; and then (2) calculate each member's genetic distance >from that haplotype. (For a fuller explanation of this, google "Maurice Gleeson modal haplotype.") I suspect that the resulting genetic distances will be less than the ones you have previously calculated. Allan Westreich
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From: "Ralph Baer" <ursusminor@verizon.net> Date: Wed, 11 May 2016 15:00:02 -0400 For several reasons, I had two of my fourth cousins take Y-chromosome tests at the 37-marker level. That is, the three of us are great-great- grandsons of three brothers, Abraham BAER, David BAER, and Lazarus BAER (me). It turns out that I differ by a genetic distance of 3 and 4 >from the two them, and they differ by 3 >from each other, which is more than what would be expected. On all but one marker where we don't all agree, two of us agree and one doesn't. E.g., on marker one, our values are 12, 13, and 12. Would it be a safe bet that the value common between the two us that agree is also the value which our mutual great-great-great-grandfather, Marx Nathan BAER had? I would think that even if two us had mutations in the same marker in the last five generations, it would not be the same mutation. The marker where we all differ is #35. The three of us have in combination with #34 values of 34-35-37, 34-35, and 34-38. Can anything be said of what the most likely value for our mutual ancestor was? It would be interesting if I could find a male-line descendant of the last brother, Kaufmann BAER, of my great-great-grandfather.
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