Thread

1. rotbart · 1791018164 · focus · HN ↗

   The strongest evidence we have of the reversibility of epigenetic aging, as well as its limitations -- are embryos which undergo an epigenetic reset.

   After fertilisation, the embryo strips the father's DNA of its age-linked chemical tags and swaps its packaging, destroys his mitochondria, rebuilds telomeres, and clears damaged proteins, though it can't undo the DNA mutations sperm gather as men age.

   (those that result in an non viable embryo result in miscarriage.)

   1. jijijijij · 1791030973 · focus · HN ↗

      Embryogenesis is an early fail-fast process. The vast majority of mutations and instabilities are caught through developmental checkpoints. Every living human passed a ruthless selection process in the womb.

      So part of the magic of that aging reversal is simply abandoning what doesn't stick. You can't do that to a grown human, obviously.

      1. someonebaggy · 1791032000 · focus · HN ↗

         You can at the cellular level. There's a hypothesis that low levels of caloric restriction or oxidative stress are essential, because they weed out underperforming cells, which are replaced.

         1. jijijijij · 1791037243 · focus · HN ↗

            This is not at all comparable to the extent of embryonic rejuvenation. Lol.

            Caloric restriction etc. just aids cellular housekeeping. The processes in maintaining gametic immortality are much more radical and transformative. Somatic and gametic genetics are governed completely differently.

            1. agumonkey · 1791043442 · focus · HN ↗

               Do you have books or articles to read about this ?

               1. jijijijij · 1791049714 · focus · HN ↗

                  All of it is a matter of active research, as this relates to the evolution of sex/sexual reproduction, which, contrary to popular belief, is still an unsolved problem in biology. Classical evolutionary theory cannot explain sexual evolution. Any book about "why?" will either be highly opinionated, agenda-driven, out-dated, or simplistic (as are my comments here).

                  I am not a biologist, so I can not refer to or evaluate any meaningful recent papers on the matter. However, I can recommend the podcast 'Big Biology', which dives into current biology research, theory and philosophy, including sexual evolution.

                  You may start here: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Evolution_of_sexual_reproduction" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Evolution_of_sexual_reproducti...

                  Richard Dawkins&#x27; &#x27;The Selfish Gene&#x27; is also an excellent read&#x2F;audiobook. His specific theories of the evolutionary &quot;unit&quot; have been disproven, but his argumentation teaches a lot about &quot;evolutionary thinking&quot;. I really wish he stuck with biology and science education instead of becoming this reactionary giga twat.

                  1. Ratelman · 1791053822 · focus · HN ↗

                     What do you mean when you say sexual evolution?

                     1. jijijijij · 1791056081 · focus · HN ↗

                        The evolution of sex and sexual reproduction, as opposed to other means of reproduction. It is inherently tied to the difference in genetic maintenance&#x2F;repair mechanisms between germline and somatic cells. See wiki link above.

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