Re: Moorad's comment is sound

In a message dated 6/24/2005 11:21:58 AM Eastern Standard Time,
rich.blinne@gmail.com writes:
You still haven't acknowledged who Montgomery Slatkin is. From Cochran's
acknowledgements:

"We are grateful for comments and help from many colleagues, not all of whom
agree with our model. ... Slatkin helped us with the population genetic
simulations."

He also referenced this paper on this:

Slatkin, M. Am J Hum Genet. 2004 Aug;75(2):282-93.
A population-genetic test of founder effects and implications for Ashkenazi
Jewish diseases.

Slatkin is widely published in genetics and his computer programs are widely
used. He also helped Cochran run his program. This is the same person who gave
those quotes. Note the strange acknowledgement "not all of whom agree with
our model".

So when Slatkin says he doesn't know anyone who thinks it's true, it's
relevent. The polite part is how forcefully do you say that it is wrong. An example
of a "less polite" geneticist from the NT Times:
The authors "make pretty much all of the classic mistakes in interpreting
heritability," said Dr. Andrew Clark, a population geneticist at Cornell
University, and the argument that the sphingolipid gene variants are
associated with intelligence, he said, is "far-fetched."
The bottom line is the genetics community still believes that the diseases
are caused by founder effect and find the current research wanting (to different
degrees). The most favorable reaction I've seen is from Dr. David Goldstein
in the NY Times article. At best, Cochran has an unproven hypothesis that
hasn't been "ruled out" over and against "quite a strong case" for founder effect.

Here's Slatkin's hypothesis addressed as it had to be to secure Harpending's

Table 4 refers to mutations introduced during the hypothesized early
bottleneck at AD70.
Simulations of a mutation introduced during the later hypothesized
bottleneck, after the
plague and the Crusades in 1350AD, never reach a frequency of 2% in our
simulations.
This is in agreement with Slatkin’s conclusion that if a bottleneck were
responsible for
the high frequency of Tay-Sachs it must be the early and not the late one.
These simulations show that the scenario of a severe early bottleneck coupled
with a low
migration rate is the only one in which there is a reasonable chance of
recessive lethal
mutant reaching a frequency of 2% by drift alone.

***The low genetic distance between
Ashkenazi and European populations denies this scenario, however, and we are
left with
the conclusion that the bottleneck hypothesis is wrong.****

I'm not going to argue this point any further.

Please read the paper, not the Jewish Forward. Steven Pinker said the paper
was not PC, but he didn't say it was wrong. Jewish torah scholars support the
paper when they admit in their own religious books that Jews "self select."
(Lamm, The Jewish Way in Love and Marriage.) Incidentally, Harpending does not
read Torah scholars and so could not use their quotes in his arguments. He knows
now since I posted them on evopsych where Harpending is a member.

rich faussette
Received on Fri Jun 24 13:01:28 2005