4 ms·
Disclaimer: I’m not in these fields but I am curious enough about how the mechanisms work at a high level that I feel confident about the rest of this post. Tw
by yazaddaruvala 5y ago
Disclaimer: I’m not in these fields but I am curious enough about how the mechanisms work at a high level that I feel confident about the rest of this post.
Two things to keep in mind:
1. Biology has never selected genes to maximize longevity, only to maximize healthy breeding. There are very likely tons of genes that make sense as a growing child but are harmful at a later age, e.g. a post menopause/vasectomy adult does not need the genes to create gametes but those same genes may be causing cancerous issues for some.
2. Gene therapy (at least CRISPR-Cas9 like things) are in theory reversible[0]. Diagnose the cancer. Delete the notable gene or just make a point mutation to disable it. Treat/wait the cancer into remission. Re-add the notable gene or re-enable it with a point mutation. Hopefully such a strategy would minimize any long term effects and eliminate the cancer.
[0] There may be cases where a bio-engineer could design an effective yet irreversible edit. However, that seems like it would require serious effort and I doubt it would have enough value to be approved by the FDA for use.
- konschubert 5y agoAlso, evolution isn't "complete". It's not done optimising. And sometimes, some things evolve and there just isn't enough evolutionary pressure to remove stuff that does't hurt. Men have nipples.
- koheripbal 5y agoCancer definitely hurts.
- monopoledance 5y ago> Men have nipples. Just sayin', that has little to do with "remove stuff that does't hurt", but the fact that there is very little difference between men and women besides sex steroid levels. In particular, women do not have any genes men don't. The Y-chromosome adds the tiniest modification to gonadal development in embryos and that's it; androgens do the rest. With the right hormone levels, men can develop fully functional breasts; without estrogens, women don't.
- manmal 5y agoAdding to point 2, gene therapy‘s effects seem to wear off after a couple of years.
- majkinetor 5y ago> Biology has never selected genes to maximize longevity, only to maximize healthy breeding. That is assumption which is hard to validate. There is a case for longevity as children with longer living dedicated parents in the context of abundant resources will out survive those that are ditched by their parents. > Delete the notable gene or just make a point mutation to disable it. The article say that effect is the same with deletion and drug in mice. Why would you delete the gene when you can temporally prevent its function ? > Delete the notable gene or just make a point mutation to disable it. Treat/wait the cancer into remission. Yet nobody did nothing remotely close in humans, even for stuff that looks like highly beneficial in all contexts such as GULO gene.
- koheripbal 5y agoI agree with your sentiment, but this condition... > in the context of abundant resources ...has only been true for a tiny number of generations and so likely has not had a large evolutionary influence.
- majkinetor 5y agoAbundant is probably too strong word. Obviously the system can't work to the extreme due to the limited resources, but there is lot of possible contexts that can last for a long time.
- fasteo 5y ago>>> 1. Biology has never selected genes to maximize longevity, only to maximize healthy breeding. There are very likely tons of genes that make sense as a growing child but are harmful at a later age, e.g. a post menopause/vasectomy adult does not need the genes to create gametes but those same genes may be causing cancerous issues for some. This is being debated, in the sense that there is a relationship between longevity and breeding. How ? For a human to be able to have kids every 2-3 years - instead of 6-7 in apes - older individuals have to be healthy enough to bring a calorie surplus to the mothers.