Re: ASPM allele origin dated to Adam's time

D. F. Siemens, Jr. wrote:
> On Thu, 20 Oct 2005 17:12:14 +0200 Peter Ruest <pruest@mysunrise.ch>
> writes:
>
>>Hi, all
>>
>>I just read a recent News article about human evolution: M. Balter,
>>"Are human
>>brains still evolving? Brain genes show signs of selection", Science
>>309 (2005),
>>1662-1663. My quotations in the following are from Balter's
>>comments. Two
>>studies "led by human geneticist Bruce Lahn of the University of
>>Chicago"
>>[Science 309 (9 Sept. 2005), p. 1717 and 1720] "conclude that two
>>genes thought
>>to regulate brain growth have continued to evolve under natural
>>selection until
>>very recently". I haven't yet read the two original articles, but
>>wanted to ask
>>for your comments now.
>>
>>"Lahn's group focused on two genes, ... microcephalin and ASPM",
>>mutations in
>>which "cause microcephaly, in which the brain is severely reduced in
>>size." Both
>>genes "have come under strong natural selection since the
>>chimp-human split" ~6
>>Ma ago. Sequencing the two genes in 90 human cell lines provided
>>"evidence that
>>selection had operated on [them] much more recently - since the rise
>>of modern
>>humans." For both genes, one of their alleles occurs at
>>"surprisingly high
>>frequency ... unlikely to be due to random genetic drift or
>>population migration".
>>... (snip)

> Peter,
> I read the article. As a total layman in the area, I thought it gave
> solid evidence. As is always the case, the dates have large standard
> deviations, so there are various possible applications or
> interpretations.

That's right.

  However, since not all humans have the same gene,
> perhaps there are the more human and the less human, or perhaps those
> that look human but are not quite human. I may not be interpreting
> matters correctly, but I strongly suspect that I don't want to go there.

All humans do have two copies of this gene, but not all have the same alleles
(detail sequences) of it. The qualifications "more human" and "less human"
certainly don't apply, and the genes under consideration have probably not much
influence on how one looks.

> On the other hand, the evidence fits clearly with change in /Homo sapiens
> sapiens/. The species did not become unalterable 7000, 50,000 or whatever
> years ago.
> Dave

I fully agree with this.
Peter

-- 
Dr. Peter Ruest, CH-3148 Lanzenhaeusern, Switzerland
<pruest@dplanet.ch> - Biochemistry - Creation and evolution
"..the work which God created to evolve it" (Genesis 2:3)