"Jan Coetzee" <coetzee_jv at news.campus.mci.net> wrote:
>Duane Hewitt writes:
>"There seem to be two possibilities:
>1) The early embryo has some telomerase activity which restores the
>telomeres. This would mean that adult cells could be rejuvenated in their
>telomeres.
>2) The cell that the successful clone was derived from had long telomeres
>and that was why it was able to be cloned. Some stem cells in adults have
>detectable telomerase activity and it is quite possible that the cell that
>Dolly arose from was one of these and therefore is a relatively "rare"
>occurence."
>There is a third possibility!
>Telomeres may have nothing to do with cell division in these particular
>cells. The telomere hypotheses is not universally true.
As far as I know there is an awful lot of evidence pointing to
telemeres being genetic clocks. It will be interesting to see what
effects the possibility of shortened telomeres has on Dolly.
In order to determine if telomeres do in fact play an important role
in the aging process it may be important to know if the adult genetic
material used to clone Dolly, was at anytime subject to telomerase
activity.
Which comes to my question. Does anyone know if female gametes are
telomerase active? Sperm are apparantly telomarase active and it
would make sence for ova to be telomarase active as well. Also, if
the adult genetic material was in fact subject to telomarase activity
how much would this telomarase activity extend to telomeres?
It seems likely that even if the adult genetic material was subject to
telomarase activity Dolly's telomeres will probably not be as long as
telomeres occuring in an uncloned lamb, but then I'm just speculating.
Regards,
James Puderer.
