4 ms·
It's been some time since I've worked in biology, but: telomere shortening is mostly a protection against aberant growth (ie, cancer): it sets an upper limit to
by kettleballroll 5y ago
It's been some time since I've worked in biology, but: telomere shortening is mostly a protection against aberant growth (ie, cancer): it sets an upper limit to how often a cell can multiply. If we'd live long enough that even healthy cells run up against that limit, we'd have to deactivate/reverse that mechanism. But then we'd lose one very effective defense against cancer.
- subroutine 5y agoThe mystery is that cell division isn't an issue for germline cells, like SSC, which replicate many times during your lifespan, and then keep on replicating during lifespans of all your progeny. https://en.wikipedia.org/wiki/Spermatogonial_stem_cell https://en.wikipedia.org/wiki/Spermatogonial_stem_cell That our germline cells are immortal, yet we are not, suggests that we (our bodies) are merely a replication vessel. Humans don't live to be 150 because (according to natural selection pressures) it's easier to just make a new version of you (or several) than to waste DNA space on efforts to keep 100-year-olds alive. The genome only serves the host through child-bearing years (plus a few extra bc grandma may still be useful to the survival of her grandchildren; what happens to grandma after 90 years old the germline cares not.
- LinuxBender 5y agoThere are some other compensating controls that can mitigate cancer but it takes some willpower which I suppose is an entirely different topic all together. This video [1] is worth a watch to learn a bit more about cancer as a metabolic disease. [1] - https://www.youtube.com/watch?v=06e-PwhmSq8 https://www.youtube.com/watch?v=06e-PwhmSq8 [video]