That was... never a theory. It can't explain aging, because telomeres are either present or not, but aging is a gradual process. (Telomerase is something entirely different, the enzyme that adds telomeres to the DNA in gametes.)
Telomeres are also unimplicated in progeria ( https://en.wikipedia.org/wiki/Progeria ), which would be a serious problem if people thought aging was caused by loss of telomeres.
The shortening of the telomeres is a protective mechanism against the development of cancer. But it only applies to non-stem-cells. In contrast, (adult) stem cells keep their telomeres intact and can divide themselves an unlimited number of times. Some of the stem cells develop into non-stem-cells when the supply of non-stem-cells becomes low.
There are many factors to aging. DNA damage, that is not repaired, accumulates over the years. And then there are also damages to the tissue on the microscopic and on the macroscopic scale that don't fully heal.
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It potentially could be used to stop ageing no? Isn't it mostly caused by accumulation of cell damage?
Last I remember aging is primarily the telomerase unwinding at the end of each chromosome over time.
that is what i learned 25 years ago too, but apparently the leading edge of gerontology has moved on, and new theories have emerged
That was... never a theory. It can't explain aging, because telomeres are either present or not, but aging is a gradual process. (Telomerase is something entirely different, the enzyme that adds telomeres to the DNA in gametes.)
Telomeres are also unimplicated in progeria ( https://en.wikipedia.org/wiki/Progeria ), which would be a serious problem if people thought aging was caused by loss of telomeres.
The shortening of the telomeres is a protective mechanism against the development of cancer. But it only applies to non-stem-cells. In contrast, (adult) stem cells keep their telomeres intact and can divide themselves an unlimited number of times. Some of the stem cells develop into non-stem-cells when the supply of non-stem-cells becomes low.
There are many factors to aging. DNA damage, that is not repaired, accumulates over the years. And then there are also damages to the tissue on the microscopic and on the macroscopic scale that don't fully heal.
Human senescence consists of many different processes, telomere attrition is one of them.
Announcers voice, 'No'