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Archiver > DNA-R1B1C7 > 2010-08 > 1282651936


From: David Ewing <>
Subject: Re: [R-M222] How long has M222 been in Scotland?
Date: Tue, 24 Aug 2010 06:12:16 -0600


Sandy Paterson says, "Now consider the range of gd's between pairs of 67
marker M222 haplotypes. They range from zero to 29 (possibly higher, but 29
is the highest I've seen), with plenty of them larger than 20."

Really? I have not studied this systematically as Sandy has, but this is
quite surprising to me. I have had the impression that for the most part
37-marker genetic distances between pairs of R:M222 haplotypes are within
about 10 and that genetic distances between pairs of haplotypes in all of
haplogroup R are within about 30. Inter-haplogroup distances (as between R
and I or R and G) are more like 50. Genetic distances between members of a
family run more like 5.

Maybe my impression results from the fact that I have confined my attention
mostly to the results of our own Ewing project. I wonder if anyone has
published an analysis that shows the distribution around a mean of pairwise
genetic distances within R:M222. My guess is that there would be a curve
starting at a percent or two at genetic distance zero, rising to a peak at
about genetic distance ten, and then with a long tail with only a percent or
two at genetic distance 15 or more. In our project, among R:M222 Ewings we
have almost a negligible amount of variation in markers 38-67, and virtually
all of us match the R:M222 modal at those markers, so my (very possibly
mistaken) idea is that the 67-marker numbers wouldn't be terribly different.

Am I dripping wet, or just slightly damp?

David Ewing

PS. It has been some time since I thought about this, and it occurs to me
belatedly that the numbers I speak about may be genetic distances from the
modal of each group rather than pairwise genetic distances. Would the
average pairwise distance between haplotypes be double the average distance
of individual haplotypes from the group modal? DNE

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