If you are referring to the telomere mediated mechanism of cell death then
there appears to be disagreement in the scientific community. Below are
two relevant excerpts from the New York Times:
January 20, 1998
Cell Rejuvenation May Yield Medical Advances
by Nicholas Wade
begin excerpt:
Third, the aging of cells in the test tube is not necessarily the same as
the aging of tissues in the body. Do people in fact die because their cells
run out of telomeres?
"If it is true that our life span is dictated by telomere shortening, then
you would imagine that some humans die because their critical cells run out
of telomeres, and there is no evidence for that at all," said Dr. Robert
Weinberg, of the Whitehead Institute, in Boston. "It is plausible that the
telomeres are long enough to allow all of us to live to 200."
end excerpt
January 18, 1998
Longevity's New Lease on Life
by Nicholas Wade
begin excerpt
Turning on telomerase permanently would sabotage a vital defense against
cancer cells. But perhaps the gene could be flicked on just long enough to
rebuild telomeres. Would this postpone aging?
No one knows for sure. Cells in a test tube and people may age differently.
And the body is composed of two main classes of cells, those that never
divide after the fetus matures and those that divide a lot. The dividing
cells are those of tissues and fluids that get a lot of wear and tear, like
the skin, blood and stomach lining.
Scientists are divided on whether these wear-and-tear tissues give out for
lack of long telomeres. If they do, then rejuvenation might help.
But many other cells don't divide at all during adult life, including the
neurons of the brain. No one knows what governs the aging of these cells.
Turning on telomerase "is not going to take care of your Alzheimer's,
skeleton atrophy and cataracts, so it can't address all aspects of aging,"
said Dr. George M. Martin, an expert on aging at the University of
Washington in Seattle.
end excerpt
Gregory Sullivan