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From: "Ken Nordtvedt" <>
Subject: Youth of Western I1b
Date: Sun, 1 May 2005 07:27:50 -0600


I was upgrading my Western I1b (the variety with the unusual DYs388 = 15 and western Europe geographical distribution) with the latest Sorenson data and found an unusual distribution at DYS390 and two other markers which did not make sense. There was an outlining "tail" of haplotypes found with the very low DYS390 = 20. On checking the pedigrees it turns out they are Polynesian. Checking the literature, it indicates that a very large fraction of Cook and Samoa Islanders have the very rare short DYS390 alleles; and they look like they are probably from Haplogroup O. In any case, stripping them from my Western I1b population using another marker, DYS448 found to totally correlate with the DYS390, one must add DYS448 = 18 (an unusual modal value in its own right) to the root definition of Western I1b. This leaves 42 haplotypes of Western I1b in the Sorenson database.

They have very low variances on the 24 markers which can be compared to my root I1a population, showing only 43 percent of the variance of my I1a standard. Based on the 10,000 year estimated age for the standard, this yields a 4300 year age for the Western I1b.

Here is the total 6 marker core haplotype I used in Sorenson to then obtain the repeat distributions for the 7th marker (which ranged over the 24 STRs)

YCAIIa,b = 21,21; DYS388 = 15; DYS448 = 18; DYS454 = 11 = DYS455; DYS462 = 12

Its DYS 19, 390, 391, 392, 393, 385a,b, 389i modal haplotype is then 15,23,10,11,13,(12,15),14 and highly so except for 389i which also has significant population with 13 repeats.

This I1b variety's very young age requires another careful look at its geographical distribution in northwest Europe which is rather different than that of the normal I1b of eastern and southeastern Europe.

Ken

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