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From: Vincent Vizachero <>
Subject: Re: [DNA] eastern R1b1c modal (was DYS 389-2)
Date: Tue, 12 Feb 2008 18:46:38 -0500
References: <200802121308.m1CD8fht014060@mail.rootsweb.com>
In-Reply-To: <200802121308.m1CD8fht014060@mail.rootsweb.com>


I believe that the difference in estimated ages for ht15 and ht35
might help us understand the LGM-era movement of R1b1c.

First let me issue the standard caveat that R1b desperately needs
(and deserves) a focused study along the lines of the studies that
have emerged on E3b, I, and J among others. Only a detailed an
extensive study can properly test the many theories on the subject.
But having said that, here's my take.

The evidence points to a southwestern Asian (and I include the
Caucasia in that group) as the point of expansion for just about
every subclade of R1b1 that I have studied. R1b1b appears to have a
southwestern Asian (SWA) origin, not a Central Asian origin as
postulated by Spencer Wells and others. Four of the six major
clusters of R1b1* that I have identified are found almost exclusively
in Jewish and/or Near Eastern populations. The origin of the other
two is uncertain - they are young and found in the UK mostly - but
I wouldn't rule a crypto-Jewish affiliation for them.

It appears that ht35 is older than ht15, by a little bit at least,
and ht35 is found at high concentrations in SWA and in Jewish
populations. Moreover, on the markers where ht15 and ht35 differ
(DYS393, DYS461, DYF385, etc.) ht35 has the same modal values as
R1b1b. In short, ht35 maintains the ancestral value and ht15 has the
derived value.

There is little doubt that ht15 expanded out of Iberian peninsula at
the end of the last ice age, but my personal theory is that it
arrived in Iberia after the LGM and before the Younger Dryas. In
other words, R1b1c expanded out of SWA at the end of the LGM only to
be forced back south during the Younger Dryas. For whatever reason,
either during the journey from SWA to Iberia or during a bottleneck
in Iberia itself, the split between ht15 and ht35 manifested.

This explanation explains the most basic facts: dual radiation
patterns from separate refugia, largely similar founder haplotypes,
and the closer similarity of the R1b1b modal to ht35 than to ht15. I
cannot think of another explanation that accounts for all the known
facts more neatly.

Vince


On Feb 12, 2008, at 8:08 AM, Elizabeth O'Donoghue wrote:

> Since it is suggested that R1b’s origins are in the Caucasus or
> thereabouts,
> would this 10-20% adequately explain the difference in the
> expansion of
> Iberian R1b1c after the LGM compared to whatever amount of R1b1c
> might have
> ‘stayed home’, or could R1b1c have developed in Iberia and traveled
> as far
> as it is now found in southwestern Asia?


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