----- Original Message -----
From: "Dominic Fox" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, November 04, 2005 12:25 PM
Subject: Re: Epigenetics
Lysenkoism!
Man, I'm really going to hate having been wrong about that one...
Dominic
--
Douglas Clark wrote:
> I should have added that I decided it was not strictly Lamarckism cos it
> was
> not the DNA that was affected but the switches that controlled the genes.
>
ie that the response to the stress was not a novel mutation.
Switches that control genes are themselves coded in the DNA,
ultimately, of course. The presence of a site in a gene which responds
to a 'switch', and the 'switch' itself, be it another gene product
(enzyme) or the *product* of another gene product (simpler molecule),
or a stacked complex which can 'tell the time' - know *when* to switch
on or off - all of this is ultimately coded for by the genome. And this
provides for some very subtle mechanisms, which don't preclude the
adaptive success of a gene which modifies another in germ cells in
response to a stress, and makes progeny more resistant to that stress.
Such a gene could be successful, even if it does not directly benefit
the individual (as is the case with many adaptations which improve the
success of progeny rather than the original bearer).
The long reach of the gene - I don't think Dawkins will be too worried
at this stage.
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