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. pasquinelli · 1791033035 · focus · HN ↗

            do you mean to say low levels of caloric restriction, or low levels of caloric intake?

            1. someonebaggy · 1791039112 · focus · HN ↗

               A small amount of adverse conditions.

               1. tclancy · 1791045212 · focus · HN ↗

                  If that works, just think what a heroic amount could do!

                  1. wizzwizz4 · 1791045955 · focus · HN ↗

                     It can weed out all your cells!

Unofficial Hacker News client; not affiliated with Y Combinator.