Is rejuvenation or significant life extension even on the radar yet?

I do. Not me, of course - I want to live forever. But I think about the politician and billionaire class that rules the world, and I think how even more doomed humanity would be if none of them ever went away. Entropy must always be there to rescue us from ourselves.

There would still be death of course– accident, suicide, murder; just a slower turnover. I’ve wondered if murder might be more common if the elite didn’t retire or die, but then of course with longer lifespans the up and coming might be willing to be commeasurably patient.

Yeah. I used to read books about life extension and futurism, back in the 1980s and 90s. One common thing that that came up was how there was a lot of political and financial pressure against longevity research from life insurance companies and religious groups. Pretty much every book mentioning life extension I ran across back then would have a section devoted to some priest talking about how it’s important that people age and die because that leads to fear and despair, which leads to faith; therefore aging and death are good things. It used to be that about the only way to do serious research on longevity was to have some private backer, because a successful experiment in prolonging the life of a lab animal would otherwise get funding shut down.

The political environment changed since then, resulting in serious research into the matter being allowed. But in practice it’s not a very old field due to it being artificially stunted for so long.

Genetics is thought to account for only about 20-30% of longevity^, surprisingly. This is significant, but hardly the full story. Epigenetics, the system that affects which genes and proteins are actually transcribed is shaped by upbringing, lifestyle and even recent experiences - turns out to be very significant. Much of this was dismissed until recently as “junk DNA”, the majority, which differs a lot more in mice and humans than the encoded genes which are largely similar, and what is meant when saying people and gibbons share 98% of DNA..

^Some studies range from 7-50%, but 20%, probably a little more, reflects the better ones.

https://mcpress.mayoclinic.org/healthy-aging/how-much-do-genetics-influence-the-aging-process/

I think this is also tied into the “cope” that we’ve been doing for millennia.

The status quo is usually contrasted with living eternally; not even being able to end your life. People talk about how “boring” it would be and it makes them feel a bit better about the lifespan and healthspan we currently have.

So in some cases people find the idea of life extension distasteful because of this framing. They dont stop to think it’s just some BS we tell ourselves, and unkillable immortality is not a physical possibility in our universe.

I was going more by stuff like this. I get the impression that the older a person is, the bigger the effects of genetics.

We found 281 genetic markers that are 61% accurate in predicting who is 100 years old, 73% accurate in predicting who is 102 years old or older and 85% accurate in predicting who is 105 years old or older. In other words, the prediction gets better with older and older ages beyond 100 which goes along with our hypothesis that the genetic component of exceptional longevity gets greater and greater with older and older age.

These 281 markers point to at least 130 genes, many of which have been shown to play roles in Alzheimer’s, diabetes, heart disease, cancers, high blood pressure, and basic biological mechanisms of aging.

I would argue that the older one is, the greater the importance of the epigenetics. In Europe, about 1 in 5000 people currently live to be 100. I think this study better than the one you cite. It is hard to be accurate and adequately powered given the paucity of 105 year olds.

This study (free, full paper below) stresses not just DNA maintenance and genes, but mRNA quality, noncoding RNAs, transcription methylation and modification of various RNAs, mTOR and translation fidelity, mitochondria, proteodynamics, autophagy … it is a complicated subject!

Yes, which is basically irrelevant to the question. Living things are constantly generating a prodigious amount of entropy. That doesn’t imply that the entropy is all in our bodies. You can keep one part of a system going indefinitely, so long as you run down other parts.

Sure, it is just that you put someone on healthcare that wants to outlaw/is outlawing the only effective medical means that has significantly extended life expectancy.

You also should do something about antibiotics.

Even if we could some how manage to rejuvenate other organs or prevent physiological senescence of the body as a system, the brain appears to have a ‘genetic clock’ that controls gene expression which drives neural and cognitive function. From a previous thread on the topic:

Stranger

Hitting the nail on the head! In the Japanese anime series, “Ghost in a Shell”, the premise was that the human brain could successfully be moved to a synthetic body and thus lengthen lifespan indefinitely. Unfortunately, the fatal flaw with that scenario is the natural deterioration of the human brain itself.

A possible solution (which admittedly we are nowhere near to being able to do at present) would be to introduce young cells into the brain to replace the dying ones, and rely on the brain’s own learning ability to ensure they wire themselves up correctly. But that’s firmly in sci-fi territory at present.

And of course there’s other sci-fi-ish concepts like uploading; but really, that’s the point. It’s wrong to claim radical life extension is impossible “because of entropy” or whatever, there’s a number of theoretical ways to pull it off. The body is just a squishy machine after all, it doesn’t run on magic; we just don’t have the knowledge needed to keep it properly repaired indefinitely. But just because it’s not impossible that doesn’t mean we’ll be able to do it anytime soon.

And whoever makes significant inroads in that direction it won’t be America, what with the way we’ve gone to war on science. Our life expectancy is going to get shorter, not longer for the foreseeable future.