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Archiver > GENEALOGY-DNA > 2009-12 > 1260291330


From: David Faux <>
Subject: Re: [DNA] R-U152 and R-L21 on the European Continent
Date: Tue, 8 Dec 2009 08:55:30 -0800
References: <mailman.279.1260259242.26095.genealogy-dna@rootsweb.com><A93225B377724B83BF5250F368878955@anatoldesktop>
In-Reply-To: <A93225B377724B83BF5250F368878955@anatoldesktop>


Anatole,

In my view the only acceptable dating procedures are direct observations -
all others have not only their limitations, but also are in danger of giving
wildly differing readings depending on the assumptions which are made.

My Canadian home is near a miromictic lake where sediments since the Ice Age
has been accumulating in two layers each year. The lake does not "turn
over" in the spring so the sediments are undisturbed. In looking at core
samples for the year 1525 there was corn pollen present that was not there
in the layers of the previous years. The assumption was made that a Native
American settlement was relatively close. Archeeologists then found the
village on a plateau overlooking the lake. I trust this dating and it can
be used to calibrate other procedures. No statistical inferences need be
made - just counting layers.

Last time I checked C14 dating had to be capped at about 40,000 years and by
then the dates were controversial - even 20,000 years created some
nervousness especially if there was even the possibility of trace amounts of
carbon from other sources such as coal. For earlier samples it is necessary
to rely on potasium argon dating or newer techniques. The first method is
based on a clear rationale about the change from one form of carbon to
another over time via half - life. Alas, time - related environmental
changes mean that correction factors need to be introduced, and from time to
time re-evaluated. Is this not what Zhivotovsy is doing?

You said that a "correction" was introduced for STR back mutations. How can
we be sure that this factor is correct or even close? There must be cross
validation. One published paper alone does not wash away all concerns. I
admit that I have not read the paper you reference, I do not have access to
it. I would like to also see the letters that were submitted after the
paper was published and, inevitably, the papers which fail to support this
inference about the supposed lock step unchanging nature over "millions of
years" of microsatellite mutation rates. A red flag goes up here - for
now. Are they speaking of autosomal STRs, because if they are, and assuming
for the moment that the authors are correct, can we assume that the X and
the Y (the sex chromosomes) play by the same rules? The inheritance pattern
of the X follows the Fibonacci series of numbers - its mutation rates are
affected by the fact that male and female mutation rates differ - more X-SNP
mutations are likely to occur in males than females. The Y is also a
special case - being concerned with the most important of all functions,
reproduction. So what is to say that over the generations it has not been
forced to adapt. Actually we know it has, and has lost many genes to other
chromosomes. Why would one assume that the mutation rate of this shrinking
violet was the same 3000 years ago as it is today? No one has observed
father - son mutation rates from Bronze Age times as they have the
bi-layered core samples from my miromictic lake.

David K. Faux.

On Tue, Dec 8, 2009 at 3:53 AM, Anatole Klyosov <>wrote:

> > From: "Bob Bootle" <>
> > Statisticians might sometimes find that the coin is bent.
>
> Certainly. It happens. Furthermore, some of them claim that a coins lands
> on its edge
> and keeps balancing there. Some even claim that a coin did not land at all,
> and is
> hanging in the air whistling Dixie.
>
> That is what science is all about. Science considers all those things,
> checks and
> verifies. Collects data and analyzes them. Sorts out facts from fables and
> manipulations.
> Explains things.
>
> Folks who work with mutations in haplotypes keep working and analyzing new
> and new data.
> And they come again and again to the conclusion that STR mutations have the
> same frequency
> now and thousands and millions years ago. There is not a single proven fact
> or an observation
> which would show otherwise. Recently a paper was published (Sun, J.X.,
> Millikin, J.C.,
> Patterson, N., Reich, D.E. 2009. Microsatellites are molecular clocks that
> supports accurate
> inferences about history. Mol. Biol. Evol. 26, 1017-1027) which showed that
> mutations are
> ticking with a constant rate for the last two million years at least.
>
> David F. keeps repeating that he is in doubt. This is fine. Some people are
> comfortable when
> they are in doubt. Other work to resolve their doubts.
>
> A similar question was with radiocarbon measurements - what if the
> measurement basis
> is now different compared with what it was thousands and millions years
> ago? People worked hard
> to answer that question. It was answered - yes, it was different. A
> correction was introduced.
> This is what science is about.
>
> Regarding STR mutations it was a similar situation, and a correction for
> reverse mutations
> was introduced.
>
> It might well be that in the future something else will be discovered and
> corrections will be
> introduced. This is how science is developing.
>
> Anatole Klyosov
>
>
>


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