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When my intro to genetics teacher in college explained to us how aging in cells worked, he told us that one of his professors had explained to him that a "cure"

When my intro to genetics teacher in college explained to us how aging in cells worked, he told us that one of his professors had explained to him that a "cure" for aging was about 10 years away. But that had been more than ten years earlier. My professor said that he had recently talked to that same professor again. The new ETA: about 10 years. This is one of those problems that seems easy to solve in principle, but the details are nasty. Frankly, I think there's a reason complicated life evolved so that it would age. The standard reason given is that eventually errors in replication accumulate and cancer results. I.e. we age to avoid cancer. But that is a ridiculous reason. There is a chance we might die of cancer if we grow too old, so we trade that possibility of death by cancer for a certainty of death by aging? It just doesn't make evolutionary sense. I have a feeling that whatever the real reason for aging is, it will take us a long, long time before we find a way around it.

javanix 16y ago
I doubt that we'll ever find a "reason" for aging. It's the result of an imperfectly optimized biological system - after all, humans are the result of one great big evolutionary algorithm. We've proven time and again that those run exponentially and are not perfectly accurate, especially in the presence of a dynamic environment.
- FlorinAndrei 16y ago
  If it's an imperfect mechanism, then look back at the huge chain linking you to the first living creature: adult body / sperm & egg / adult body / sperm & egg / adult body / ... How come that chain hasn't failed? Basically, you're just rephrasing the "aging through accumulation of errors" hypothesis. The problem is, errors should accumulate along the chain mentioned above, too. Yet they don't.
  - crystalis 16y ago
    The chain gets to weed out errors by starting with cells that got through functionally unblemished courtesy functioning error correcting mechanisms. Each new cycle gets a fully functional error correction mechanism, and is fault tolerant to the theoretical point of repopulation from a small point of individuals. An individual human body has error correcting mechanisms that do not benefit from being renewed every cycle- they deteriorate over time, Individuals suffer from problems larger systems don't - a few cancerous cells can poison the whole individual, but a few cancerous individuals are likely to die with few offspring, and their offspring are also more likely to die with few offspring. If an individual is left with only a few correctly functioning cells, they have no recourse for rebuilding themself. Species get a constant influx of fresh water, as it were, and individuals have to make do with a set quantity.
    - FlorinAndrei 16y ago
      Where does the fresh water come from? Your assumption is that sex cells are magically exempt from the accumulation of errors.
      - crystalis 16y ago
        It's not that they are magically exempt, but that the error filled ones are less reproductively viable, and die out. That contrasts directly with e.g., cancer cells, that become more prolific and lead to the death of the organism. (There's several points of 'selection' for sex cells- error free ones are, loosely speaking, more likely to successfully fertilize/get fertilized, and more likely to create viable offspring that themselves reproduce.) Edit: It's like the difference between being able to select the top 10% and selecting those with a score above 90%. The chain gets to "select" only those that perform above a set threshold, but the organism has to play out every hand it's dealt.
jwegan 16y ago
I think part of it might be that evolution only cares about how successful you are in passing on your genes. Why do salmon die after mating (its due to exhaustion)? There isn't really any reason they have too, but they successfully passed on there genes so there is little evolutionary pressure on what happens afterward. I think it is the same for aging. There isn't really a reason for aging, it just happens because there is less evolutionary pressure once humans pass the age when they normally procreate. Of course I don't have any qualifications and this is just my hypothesis so take it as you will.
- FlorinAndrei 16y ago
  IIRC, either Kurzweil or de Grey said exactly the same thing.
- v3rt 16y ago
  I believe the predominant evolutionary theory actually does have an explanation - sexual reproduction serves to produce offspring that are different from their parents and have a better shot of being adapted to a constantly changing environment on average (particularly relevant to parasites/diseases). These children still carry their parents' genes, though, so it is in the parents' best genetic interests to die once the kids are self-sufficient so as to avoid out-competing their own offspring.
  - deleted 16y ago
    [deleted]
  - asdflkj 16y ago
    W.R.T. humans, the predominant evolutionary theory does have an explanation, and it's exactly what jwegan said. Your scenario is only relevant to organisms who live in niches very far from our own. Humans have always lived in ecosystems large enough that our kids' share of the burden of our claims on resources is infinitesimal, and certainly no comparison to benefit that kids derive from their alive parents.
- tansey 16y ago
  The reason for sticking around after mating is to protect your children. In this sense, there is definitely an evolutionary pressure to live longer. The longer an organism takes to mature, the more advanced it can become. Consequently, the longer you live as a mature individual, the longer you can mate to produce more children and protect the ones you already produced.
gte910h 16y ago
I honestly don't think we're throwing very much effort into the work.
rosser 16y ago
So we're perpetually closer to curing aging than we are to energy-positive fusion? If only they were reversed, we'd be able to support the population explosion in millenarians before they got here...
- mechanical_fish 16y ago
  Hee hee. All in support of my cynical hypothesis: the predicted future is always at least ten years away because that's slightly longer than the longest research grants. [1] See, if you predict a breakthrough in five years and are then awarded a seven-year grant, you're setting yourself up for a lot of embarrassment when it comes time to apply for a renewal. The future is in the future, and until you're absolutely certain of success it's important to keep it there. ;) --- [1] that's the predicted future. The actual future isn't in the future at all. It arrives every day, without warning, as a fait accompli. There's no money in predicting the near future: you must either predict the far future, or make the near future.
FlorinAndrei 16y ago
"I think there's a reason complicated life evolved so that it would age. The standard reason given is that eventually errors in replication accumulate and cancer results. I.e. we age to avoid cancer. But that is a ridiculous reason." Exactly. Any justification along those lines falls flat on its face when you realize it should also apply to the sperm and egg. Yet it doesn't apply in that case.
s3graham 16y ago
The "reason" for aging seems almost self-evident to me. The goal is to pass on [mutated] genetic information. Post-reproduction, you're simply a drag on local resources. Hypothetical populations that didn't age and die would have killed themselves off due to lack of food.
- MikeCapone 16y ago
  Anything that happens after reproduction is in an evolutionary blind spot. Aging is the result of evolutionary neglect, not design.
  - s3graham 16y ago
    I disagree. If my parent stays around and eats all my food, I'm carrying bad genes that cause me to die pre-reproduction.
    - fizx 16y ago
      True. The thing I wonder about is whether the development of sentience and culture is swinging evolution's pendulum away from the resource needs of the young, and toward valuing the experience and knowledge of the elders.
    - MikeCapone 16y ago
      That would be the case, and what I said up-thread was badly formulated. But it still remains that in the way things happened, aging is evolutionary neglect. We've evolved repair mechanisms that help us pass our genes, and also parents who take care of their children (since it takes quite a while for a human child to become self-sufficient), but through most of history, humans died pretty young and so we never had time to evolve repair mechanisms for the kind of damage that happens when you are 50-60, etc.
      - electromagnetic 16y ago
        I'm sorry, cite your evidence please. Humans have never 'died young', it's complete bullshit, our life expectancy has changed not our longevity. Genghis Khan died at 65 in 1227. Julius Caesar was murdered at 56 years old in perfect health in 44BC. Augustus died at 77 in 14AD. Ramesses The Great is believed to have died between 90-93 years old, in 1213BC. I'm sorry, that's 3000+ years where we know our longevity hasn't changed, especially considering all of these men entered warfare. People living to 100 with all their mental and physical strength is rare, however people living to their 60's is not and has never been. Our genes evolved to fight childhood diseases and injuries, so that those who make it through have the potential to live well into their 60's without a problem. Incidentally, those who get sick less frequently in childhood tend to have a longer lifespan as is. However the whole notion that humans only lived till 30 is absurd, because it's simply not true for any of recorded history. Yes it was the average, however that was under a very different culture. Ramesses II successor was his 13th son, who lived to his early 80's. Many of his other children either died very early or died through injury or mid-life disease. His first born for instance died from a blow to the head in his 40's. Please, don't confuse life expectancy and longevity, the two are vastly different. The former has changed drastically, the latter hasn't. Regardless of whether we avoid disease today or 3000 years ago, we'll likely hit 90 years before dying of old age 'naturally' (IE from a lack of longevity).
sketerpot 16y ago
And there's the beauty of Aubrey de Gray's plan: it's not about finding a Cure for Aging. It's about finding a number of techniques that will allow us to extend people's life-spans long enough to find out how to extend their life-spans more, which will give more time for research, and so on. It's a much more realistic approach than "finding a way around aging," which is how the problem is usually miscast.
- jacquesm 16y ago
  And Achilles never really overtook the hare right ?
Tichy 16y ago
I think it likely that aging has evolved, that is, nature wants us to die (or some organisms at least). It certainly doesn't care how long we live. That doesn't mean that we can't come up with out own motivations and schemes. There is also (afaik) at least one organism that can live forever, a jellyfish.

javanix 16y ago

I doubt that we'll ever find a "reason" for aging. It's the result of an imperfectly optimized biological system - after all, humans are the result of one great big evolutionary algorithm. We've proven time and again that those run exponentially and are not perfectly accurate, especially in the presence of a dynamic environment.

FlorinAndrei 16y ago
If it's an imperfect mechanism, then look back at the huge chain linking you to the first living creature: adult body / sperm & egg / adult body / sperm & egg / adult body / ... How come that chain hasn't failed? Basically, you're just rephrasing the "aging through accumulation of errors" hypothesis. The problem is, errors should accumulate along the chain mentioned above, too. Yet they don't.
- crystalis 16y ago
  The chain gets to weed out errors by starting with cells that got through functionally unblemished courtesy functioning error correcting mechanisms. Each new cycle gets a fully functional error correction mechanism, and is fault tolerant to the theoretical point of repopulation from a small point of individuals. An individual human body has error correcting mechanisms that do not benefit from being renewed every cycle- they deteriorate over time, Individuals suffer from problems larger systems don't - a few cancerous cells can poison the whole individual, but a few cancerous individuals are likely to die with few offspring, and their offspring are also more likely to die with few offspring. If an individual is left with only a few correctly functioning cells, they have no recourse for rebuilding themself. Species get a constant influx of fresh water, as it were, and individuals have to make do with a set quantity.
  - FlorinAndrei 16y ago
    Where does the fresh water come from? Your assumption is that sex cells are magically exempt from the accumulation of errors.
    - crystalis 16y ago
      It's not that they are magically exempt, but that the error filled ones are less reproductively viable, and die out. That contrasts directly with e.g., cancer cells, that become more prolific and lead to the death of the organism. (There's several points of 'selection' for sex cells- error free ones are, loosely speaking, more likely to successfully fertilize/get fertilized, and more likely to create viable offspring that themselves reproduce.) Edit: It's like the difference between being able to select the top 10% and selecting those with a score above 90%. The chain gets to "select" only those that perform above a set threshold, but the organism has to play out every hand it's dealt.

jwegan 16y ago

I think part of it might be that evolution only cares about how successful you are in passing on your genes. Why do salmon die after mating (its due to exhaustion)? There isn't really any reason they have too, but they successfully passed on there genes so there is little evolutionary pressure on what happens afterward. I think it is the same for aging. There isn't really a reason for aging, it just happens because there is less evolutionary pressure once humans pass the age when they normally procreate. Of course I don't have any qualifications and this is just my hypothesis so take it as you will.

FlorinAndrei 16y ago
IIRC, either Kurzweil or de Grey said exactly the same thing.
v3rt 16y ago
I believe the predominant evolutionary theory actually does have an explanation - sexual reproduction serves to produce offspring that are different from their parents and have a better shot of being adapted to a constantly changing environment on average (particularly relevant to parasites/diseases). These children still carry their parents' genes, though, so it is in the parents' best genetic interests to die once the kids are self-sufficient so as to avoid out-competing their own offspring.
- deleted 16y ago
  [deleted]
- asdflkj 16y ago
  W.R.T. humans, the predominant evolutionary theory does have an explanation, and it's exactly what jwegan said. Your scenario is only relevant to organisms who live in niches very far from our own. Humans have always lived in ecosystems large enough that our kids' share of the burden of our claims on resources is infinitesimal, and certainly no comparison to benefit that kids derive from their alive parents.
tansey 16y ago
The reason for sticking around after mating is to protect your children. In this sense, there is definitely an evolutionary pressure to live longer. The longer an organism takes to mature, the more advanced it can become. Consequently, the longer you live as a mature individual, the longer you can mate to produce more children and protect the ones you already produced.

gte910h 16y ago

I honestly don't think we're throwing very much effort into the work.

rosser 16y ago

So we're perpetually closer to curing aging than we are to energy-positive fusion? If only they were reversed, we'd be able to support the population explosion in millenarians before they got here...

mechanical_fish 16y ago
Hee hee. All in support of my cynical hypothesis: the predicted future is always at least ten years away because that's slightly longer than the longest research grants. [1] See, if you predict a breakthrough in five years and are then awarded a seven-year grant, you're setting yourself up for a lot of embarrassment when it comes time to apply for a renewal. The future is in the future, and until you're absolutely certain of success it's important to keep it there. ;) --- [1] that's the predicted future. The actual future isn't in the future at all. It arrives every day, without warning, as a fait accompli. There's no money in predicting the near future: you must either predict the far future, or make the near future.

FlorinAndrei 16y ago

"I think there's a reason complicated life evolved so that it would age. The standard reason given is that eventually errors in replication accumulate and cancer results. I.e. we age to avoid cancer. But that is a ridiculous reason." Exactly. Any justification along those lines falls flat on its face when you realize it should also apply to the sperm and egg. Yet it doesn't apply in that case.

s3graham 16y ago

The "reason" for aging seems almost self-evident to me. The goal is to pass on [mutated] genetic information. Post-reproduction, you're simply a drag on local resources. Hypothetical populations that didn't age and die would have killed themselves off due to lack of food.

MikeCapone 16y ago
Anything that happens after reproduction is in an evolutionary blind spot. Aging is the result of evolutionary neglect, not design.
- s3graham 16y ago
  I disagree. If my parent stays around and eats all my food, I'm carrying bad genes that cause me to die pre-reproduction.
  - fizx 16y ago
    True. The thing I wonder about is whether the development of sentience and culture is swinging evolution's pendulum away from the resource needs of the young, and toward valuing the experience and knowledge of the elders.
  - MikeCapone 16y ago
    That would be the case, and what I said up-thread was badly formulated. But it still remains that in the way things happened, aging is evolutionary neglect. We've evolved repair mechanisms that help us pass our genes, and also parents who take care of their children (since it takes quite a while for a human child to become self-sufficient), but through most of history, humans died pretty young and so we never had time to evolve repair mechanisms for the kind of damage that happens when you are 50-60, etc.
    - electromagnetic 16y ago
      I'm sorry, cite your evidence please. Humans have never 'died young', it's complete bullshit, our life expectancy has changed not our longevity. Genghis Khan died at 65 in 1227. Julius Caesar was murdered at 56 years old in perfect health in 44BC. Augustus died at 77 in 14AD. Ramesses The Great is believed to have died between 90-93 years old, in 1213BC. I'm sorry, that's 3000+ years where we know our longevity hasn't changed, especially considering all of these men entered warfare. People living to 100 with all their mental and physical strength is rare, however people living to their 60's is not and has never been. Our genes evolved to fight childhood diseases and injuries, so that those who make it through have the potential to live well into their 60's without a problem. Incidentally, those who get sick less frequently in childhood tend to have a longer lifespan as is. However the whole notion that humans only lived till 30 is absurd, because it's simply not true for any of recorded history. Yes it was the average, however that was under a very different culture. Ramesses II successor was his 13th son, who lived to his early 80's. Many of his other children either died very early or died through injury or mid-life disease. His first born for instance died from a blow to the head in his 40's. Please, don't confuse life expectancy and longevity, the two are vastly different. The former has changed drastically, the latter hasn't. Regardless of whether we avoid disease today or 3000 years ago, we'll likely hit 90 years before dying of old age 'naturally' (IE from a lack of longevity).

sketerpot 16y ago

And there's the beauty of Aubrey de Gray's plan: it's not about finding a Cure for Aging. It's about finding a number of techniques that will allow us to extend people's life-spans long enough to find out how to extend their life-spans more, which will give more time for research, and so on. It's a much more realistic approach than "finding a way around aging," which is how the problem is usually miscast.

jacquesm 16y ago
And Achilles never really overtook the hare right ?

Tichy 16y ago

I think it likely that aging has evolved, that is, nature wants us to die (or some organisms at least). It certainly doesn't care how long we live. That doesn't mean that we can't come up with out own motivations and schemes. There is also (afaik) at least one organism that can live forever, a jellyfish.