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From: "Tom Gull" <>
Subject: Re: [DNA] TRMCA for R1b1
Date: Sat, 29 Nov 2008 16:44:09 -0500
References: <C556259C.FA4C%bobhay@optusnet.com.au><0741DF0B-C741-4EEB-B761-C1F995CA28D9@vizachero.com><f3f05ce80811280713j4ec76a5cpda422767c2fa2150@mail.gmail.com><2B633A6B-F35A-4E4F-B341-69C4AE554EF9@vizachero.com><BAY106-DS5AEAC4A917ACDFEF9A5FBBC040@phx.gbl><360C8614-27E0-44A1-BA54-94BC736B30B2@vizachero.com>
In-Reply-To: <C556259C.FA4C%bobhay@optusnet.com.au><0741DF0B-C741-4EEB-B761-C1F995CA28D9@vizachero.com><f3f05ce80811280713j4ec76a5cpda422767c2fa2150@mail.gmail.com><2B633A6B-F35A-4E4F-B341-69C4AE554EF9@vizachero.com><BAY106-DS5AEAC4A917ACDFEF9A5FBBC040@phx.gbl><360C8614-27E0-44A1-BA54-94BC736B30B2@vizachero.com>


Thanks, Vince. I read the August thread but it was instructive to reread it.
Looking at the original paper and your thread at the same time, I understand
your points readily. Given that the substructure of RxR1a wasn't known then,
I think this becomes an interesting footnote re how theories of the
population of Europe developed, but I don't see how its conclusions based on
inadequate information can outweigh more recent evidence.

Even back then, I notice the paper actually describes two candidate
haplogroups for being a primary Paleolithic haplogroup of Europe - RxR1a and
I (M170). It chooses RxR1a (not R1b) over I without stating why, so I'm
still left thinking it was solely because everyone expected the original
population group to be represented today by the largest group now. R1b
dominates today, of course, but I is the next most prominent haplogroup in
western and central Europe from the maps I see online. On page 1156 of the
document for the study, the discussion of M170 begins:

"The polymorphism M170 represents another putative Paleolithic mutation
whose age has been estimated to be ~22,000 years (22, 23). ... We propose
that M170 originated in Europe in descendants of men that arrived from the
Middle East 20,000 to 25,000 years ago..."

Then there is some discussion of how I has been associated by some with the
Gravettian culture, and others have suggested the Gravettian and Aurignac
groups coexisted for a few thousand years. All in all, I never gets
seriously considered as a primary Paleolithic haplogroup because the nominal
dates are a few thousand years off if you ignore confidence intervals, and -
I think - because RxR1a is "bigger". As I've noted elsewhere, reading
Cunliffe's recent book and other European history tracts makes me wonder if
"[Y-DNA] history is written by the winners" suggests that highly successful
latecomers to the European scene should be expected to have left the largest
legacy instead of the original populations. Talk about an unstable
environment population-wise!

Anyway, what I'm reading so far makes me think that the core of "R1b was the
primary European Paleolithic population haplogroup" remains an untested
simplifying assumption that the largest extant haplogroup today west to east
must be the oldest. Now that we're getting deeper into issues of TMRCA
cross-clade ages and measures of genetic diversity, I think we're starting
to test that hypothesis successfully.

/ Tom
--------------------------------------------------
From: "Vincent Vizachero" <>
Sent: Friday, November 28, 2008 2:52 PM
To: <>
Subject: Re: [DNA] TRMCA for R1b1

> Tom,
>
> The basic premise of the "old argument" was laid out by Semino et al.
> in 2000. I gave a pseudo-detailed rebuttal of that paper at dna-
> forums.org in August, and it is probably too lengthy to repeat on an
> email list. Here's a link to an archived version of that post:
>
> http://vizachero.com/R1b1/SeminoGotItWrong.html
>
> And a link to the original post:
>
> http://dna-forums.org/index.php?showtopic=4223
>
> Anyway, if you review the literature the paper trail on any citation
> generally leads back to Semino 2000 and its the only paper that really
> attempts to assemble an argument in any detail whatsoever. Given
> that the paper is nearing 8 or 9 years old, hindsight makes it easy to
> spot the holes in the argument. My conclusion in August was this:
>
>> All in all, its a pretty weak case. It depends entirely on two
>> "findings": ht15 has its highest frequency in western Europe, and
>> R1(xR1a) is 30,000 years old.
>>
>> The first finding is true, but subsequent research has shown that
>> the most ancestral forms of R-M269 are in the east primarily and
>> have the highest STR diversity there (not in western Europe). This
>> one annoys me a bit, because Semino could have and should have known
>> about ht35 in April 2000 when she wrote the paper.
>>
>> The second finding is, to be blunt, dubious at best. She used only
>> three STRS, two of them palindromic, and used a bad mutation rate
>> estimate to boot. RecLOH was not as well understood in 2000 as it is
>> today, so I'm inclined to cut Semino some slack here. The finding is
>> bogus, still, but more understandable.
>>
>
> Semino lacked the ability to fully characterize what then could only
> be described as ht15: STR testing had not been widely adopted in
> 2000, and M269 had not even been discovered (much less P312 and
> U106). Also, as I mention above, her access to reasonable mutation
> rate estimates and models was much more poor than we have today. But
> her focus on frequency (as opposed to diversity) severely weakens her
> case, as does the fact that she is dating R1(xR1a) and using that as a
> proxy for the age of (under ISOGG 2008) R1b1b2a1b.
>
> Vince
>


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