> Date: Tue, 18 Mar 1997 13:24:41 GMT
Re: implications of dolly
Surely patterns of transcription can be stably maintained without
having to invoke some change in the methylation state of the DNA ?
Such patterns might, given the right environmental cues, alter to
assume a new expression-pattern (attractor ?), during progression
from embryo to adult, but needn't be the product of physically altering
the DNA. Resetting to some basal / default expression pattern either
through mating or electric shock (I seem to remember that's what the
Rosalin people did) would then suffice to produce a viable clone...
MGB
x
> I disagree with your dismissal of methylation's role in
> aging: DNA methylation patterns are reset during early
> embryogenesis. In fact, the Dolly experiment supports a
> methylation theory of aging (changes irreversible in adult
> cells but reversible in embryonal cells) over a mutational
> theory of aging (changes irreversible no matter what).
> Incidentally, there is some data suggesting that this may be
> true for some cancers as well.
> Jean-Pierre Issa
>>grendle at worldnet.att.net (jim and barbara burkhart) wrote:
