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From: ellen Levy <>
Subject: The New Basque Study: MtDNA ain't what it used to be!
Date: Mon, 11 Apr 2005 09:40:34 -0700 (PDT)


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Whitney wrote about this study earlier this month.
The study: Temporal Mitochondrial DNA Variation in the
Basque Country: Influence of Post-Neolithic Events,"
A. Alzualde, 2005, Annals of Human Genetics.

I'd like to suggest to FTDNA (if anyone out there is
reading this) that they add this study to their
library. It is, in my opinion, quite a remarkable
study, not only because it suggests that modern-day
populations may not closely resemble their prehistoric
counterparts, but because it also implies that they
Celtic/Basque DNA link is much more recent than either
the Paleolithic or Neolithic time periods.

One of Whitney's criticisms was that skeletal remains
were tested from a Basque site dating from an
historical time frame (6-7th century AD). But the
study did far more than that - it tested skeletal
remains from three prehistorical Basque sites as well,
then compared these to the historic Aldaieta site as
well as to contemporary Basque results. Little to no
difference between the historic MtDNA results and the
contemporary Basque results were discovered.

There was, however, quite a significant difference in
some of the MtDNA when those two populations were
compared to prehistoric (5000 YBP) Basque groups.
This is particularly important because it cuts across
the general acceptance of the Basques as
representatives of the "first European settlers of the
Upper Paleolithic," (ie, a relatively "pure" vestige
of ancient Europeans from pre-Neolithic times with
little to no Neolithic genetic components). This
study not only proves that this interpretation of
Basque DNA may be incorrect, but that there was
considerable gene flow among all western European
populations that resulted in the homogenization of
MtDNA lineages.

The prehistoric Basque population is set apart from
the historic (Aldaieta) and contemporary Basque
populations based on significant differences in MtDNA
haplogroups K, J, X and V.

Haplogroup K accounts for only 4.8% of modern-day
European results and 2.7% of the Aldaieta results.
But prehistoric Basque populations had a very high
frequency of K: 16-23!! As the authors note, "The
three prehistoric populations of the Basque Country
stand apart from those of the Atlantic fringe." No
kidding.

Another important difference is the discovery of MtDNA
J among prehistoric Basque groups. J is generally
regarded as a marker of Neolithic migrations out of
the Middle East. While contemporary Basque groups
have little haplogroup J, this was clearly not the
case 5000 years ago. The prehistoric groups (two out
of the three, at least) display about 16% J results,
while contemporary Basque have only 2.4%.

The researchers make a bigger deal out of the
differences in MtDNA haplogroup H than I think are
actually warranted, with prehistoric groups displaying
between 37-44% and modern day Basque displaying 48%.
It still looks to me that 5000 YBP, Basque groups
still had a very high frequency of haplogroup H - only
slightly lower than present day populations.

However, the complete absence of haplogroup V from the
prehistoric groups is remarkable considering that V is
believed to originate in southwest Europe and is found
in its highest frequency (4.8%) among contemporary
Basque groups!

Given this discontinuity between prehistoric and
historic/contemporary Basque populations, it is clear
that modern-day Basque are not truly reflective (in a
genetic sense) of Upper Paleolithic populations of
Europe. Rather, they are the product of "evolutionary
processes experienced by the Basque population some
time after the Neolithic." Interestingly, the
researchers suggest these "processes" involve extreme
intermixing between prehistoric Basque groups and
those "constituting the Atlantic fringe," (ie,
modern-day Celtic speakers) resulting in a
"post-Neolithic restructuring of the population."
Thus, the common genetic links we are hearing so much
about between Basque & Celtic groups may be much more
recent then previously believed.

Ellen Coffman


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