Thread

1. dyauspitr · 1790966547 · focus · HN ↗

   So chronic stress is one of the main contributors to aging. I hope I make it to my 40s.

   Do we currently have the ability to do targeted methylation or de methylation at sites in cells?

   1. Chance-Device · 1790971024 · focus · HN ↗

      > Do we currently have the ability to do targeted methylation or de methylation at sites in cells?

      No, and you probably wouldn’t want it if you could. You don’t know what mutations are lurking in the genes that have been switched off or the consequences of turning them back on.

      I’ve thought about this a bit, and what resetting the methylation map really requires, in addition to actually resetting that map, is resetting your genome to a known good state.

      That’s pretty radical, but to selectively switch methylation on and off with precision you’re already talking about science beyond anything we have, featuring custom engineered constellations of proteins that unwrap your chromatin from around histones and then walk along it changing methylation state, then pack everything back.

      And doing it for each cell type, without applying the wrong map anywhere.

      And knowing what all the cell types and their correct methylation maps actually are.

      And assuming that methylation isn’t used anywhere, for example in the brain, in a way we don’t expect.

      And methylation isn’t the only kind of epigenetic modification.

      So, if we’ve solved all of those problems, rebuilding your DNA to a clean, mutation free state at the same time should be a breeze.

      We really do need AI for this if any of it is going to be remotely feasible.

      1. yieldcrv · 1790973401 · focus · HN ↗

         in my futile searches for meaning I’ve wondered whether cancers in humans are a failsafe to something else or preventing something worse

         more specifically the lack of more failsafes seen in some other mammals are a reaction to something besides happenstance

         1. jhrmnn · 1790975932 · focus · HN ↗

            Cancer is the price we pay for complex multicellular life. It’s not a failsafe, it’s the failure of all failsafes to regulate cellular growth within an organism.

            1. yieldcrv · 1790985357 · focus · HN ↗

               Larger mammals with many more cells have additional protections against cancer

               Such as longer and more numerous telomeres

               Hence why the human situation stands out to me and can’t be reduced to “it just is“. Some other mammals have it worse though

               1. usrnm · 1791008902 · focus · HN ↗

                  Evolution doesn't care about individual organisms, it's all about reproduction. Our lifespan is enough to raise a few children and pass genes on, so, from the evolutionary point of view, it's adequate

                  1. yieldcrv · 1791010489 · focus · HN ↗

                     I understand, I'm equally frustrated when people including scientists say that something evolved for an environmental specialization, instead of the evolution being happenstance that may have incentivized more viable mutant offspring surviving until reproduction in that environment, but was not "for" anything.

                     and yes, so I understand that with human cancer, it tends to happen or advance after reproduction has already occurred so therefore those traits are not selected against. it's impossible to weed out with human mating strategies

                     I would just like to believe the cancer itself is an adaptation preventing something worse, but you're right, it doesn't work with the natural selection theory and so we just had a dead end to our survivability baked in, not so different than how the opposite phenomenon of senescence in cephalopods ends their lives

                     1. matthewdgreen · 1791029251 · focus · HN ↗

                        Everyone involved in this discussion understands that evolution doesn’t create things for a purpose, that it’s just the result of selection pressures. Everyone also uses the more active phrasing because it’s much more convenient. Unless you think you’re talking to someone who genuinely doesn’t understand the nature of the process, it’s not useful to be pedantic about it.

                        1. yieldcrv · 1791038020 · focus · HN ↗

                           We’re agreeing actually and not talking to you at all

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