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From: Gary Felix <>
Subject: Re: [DNA] R1b Origins (was OurEuropeangeographicalblock. . .)
Date: Sat, 4 Jul 2009 12:50:14 -0700 (PDT)


Seeing as to how Dieneke's believes in the Paleo. origin of the Basque you might try posting a question relating to this on his blog.

Gary
Mexico DNA Project Admin.

--- On Sat, 7/4/09, Tom Gull <> wrote:

From: Tom Gull <>
Subject: Re: [DNA] R1b Origins (was OurEuropeangeographicalblock. . .)
To:
Date: Saturday, July 4, 2009, 12:02 PM

Also interesting in relation to this whole thread (mtDNA as a stand-in for
Y-DNA, modern distribution reflecting ancient distribution, etc.):

>From Dieneke's blog at

http://dienekes.blogspot.com/2009/07/genetic-discontinuities-between.html

Part II of his discussion of a paper:

UPDATE II (Jul 2)

>From the paper:

Analyses of mtDNA diversity in the British Isles (Töpf et al. 2007), and
Iceland (Helgason et al. 2009), also showed sharp differences between
historical and current populations. In addition, a large fraction (up to
80%, depending on the region considered) of the Dutch surnames were
displaced from the areas in which their frequency was highest three
centuries ago (Manni et al. 2005). Nobody can tell whether the Netherlands
represent an exception or the rule, until similar studies are carried out
elsewhere, and there is no comparable information on previous centuries.
However, the point here is that a genetic discontinuity between present and
past populations seems rather common in the few European countries studied
so far. Deep demographic changes in the last two millennia are both
suggested by the analysis of ancient DNA in Tuscany, Iceland and Britain,
and empirically demonstrated in the Netherlands. Our failure to reproduce by
simulation the observed haplotype number of the contemporary Tuscan samples
may mean that such changes involved multiple immigration processes, too
complex to model at present.

The paper by Töpf et al. in turn points to this study of ancient British
mtDNA which I had forgotten about. That study shows an increase of
haplogroup H (as most of the OTHER probably is) in modern times compared to
the past, and the drastic reduction of some haplogroups as U5a1 and U5a1a.
Other cases of apparent drastic change over time, involves the Central
Europeans (reduced haplogroup N1a) compared to early Central European
farmers., and medieval vs. modern Danes (reduced haplogroup I).

So, the picture does seem to suggest substantial changes in mtDNA gene pools
over time across many parts of Europe and time frames. Whether this reflects
population movements or selection, remains to be seen. In the paper on the
Netherlands, for examples (Manni et al.) cited in this paper shows that the
original surnames in a region can be rapidly replaced over a genealogical
time frame.

Studies such as these put into question the widely held assumption that
modern gene pools reflect prehistorical events, such as the repopulation of
Europe after the glacial age, or the advent of farming. If genetic change is
so substantial over 100 generations, we are rather foolish, I believe, to
attempt prehistoric reconstructions about events that took place 300 or even
600 generations ago.


--------------------------------------------------
From: "Richard Stevens" <>
Sent: Saturday, July 04, 2009 7:21 AM
To: <>
Subject: Re: [DNA] R1b Origins (was OurEuropeangeographicalblock. . .)

> If one starts out by assuming that M269 is a "Paleolithic mutation" and
> that
> "the genetic component in the Pyreneans that presumably
> entered Iberia from the Neolithic era onwards" excludes any kind of
> R1b1b2,
> and then fails to use observed father-to-son mutation rates to calculate
> TMRCA, then he can reach the sort of anachronistic conclusion you have
> described below.
>
> Rich
>




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