> Does anyone know if there is data on longevity of cloned mamals yet?
> This could tell us something about the role of mitochondria in
> resetting the ageing clock.
This was asked on sci.life-extension very recently -- search DejaNews
for the thread named "Cloning may cause long-term health problems".
In brief, no one there knew of any such data. My view re mitochondria
in this context is that we would probably not learn much, because the
somatic cells that are used as the "zygote" are from populations of
cells which have been dividing throughout the lifetime of the donor
and have thereby weeded out any mitochondrial mutations as they arose.
It is non-dividing cells which accumulate mtDNA mutations during aging.
(Whether even *they* accumulate enough to matter is very controversial.)
Aubrey de Grey