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DNA has a half life of 521 years. Even if a human could be maintained at a biological age of ~30 indefinitely, would the natural decay of his DNA not kill him i
by HenryKissinger 7y ago
DNA has a half life of 521 years. Even if a human could be maintained at a biological age of ~30 indefinitely, would the natural decay of his DNA not kill him in the long term?
- ISL 7y agoIf replicated and properly check-summed that half life could be extended by many orders of magnitude.
- earthboundkid 7y agoOn a long enough timescale, you’d either die in an accident or get depressed and kill yourself just randomly within a few hundred years. The oldest wooden houses are only one thousand years old. https://en.wikipedia.org/wiki/Kirkjub%C3%B8argar%C3%B0ur https://en.wikipedia.org/wiki/Kirkjub%C3%B8argar%C3%B0ur The human body is way more delicate and less likely to survive. Even with extreme motivation, no human will see the death of our Sun, let alone the heat death of the universe.
- tempestn 7y agoIt depends; if you could hypothetically buy yourself a few hundred years, that might be long enough for other techniques to preserve consciousness. Brain state backups, say. Not saying that will happen, but it's not inconceivable.
- kiba 7y agoI don't really think brain state backup as extending your life.
- tempestn 7y agoNot on its own, but it would be the final piece in living effectively forever, since it could protect against accidents that would eventually take out even people who never aged or got sick. Unless you mean that a copy of your brain would not longer be 'you'. In that case I just disagree. We don't know the level of fidelity required, but it seems extremely likely to me that if my brain were copied to a sufficient level of precision, whatever that level might be, the copy would continue my subjective experience.
- markyc 7y ago> the copy would continue my subjective experience. it may, but it wouldn't be "you". "You"'d experience death, and something else will exist independent of "you", but with most of the same features and memories.
- tempestn 7y ago"I" am my thought patterns and memories. It would be me as much as I'm still me when I wake up each morning.
- codeisawesome 7y agoI agree with this - but Altered Carbon had this interesting couple scenes where more than one copy of a dude exists. What’s “you” in that event? If we can guarantee teamwork of the clones, we have a new status symbol - else we have created some severe ego/identity problems.
- AmericanChopper 7y agoYeah I agree with this. As soon as two copies of you exist, your life experiences immediately diverge, and I wouldn’t say you could reasonably be considered the same person. I also think that copying your conscious state from one body to another creates a new person in any case. Everybody except you (including the copy) may consider the new person to be exactly the same as you, but you will now be dead.
- hexaga 7y ago[citation needed] Somewhat tongue in cheek, but the point remains. What leads you to believe this? As another reply touches on, there's a straightforward way to verify whether that is the case (for oneself, and not an external observer): Given a perfect clone, uploaded copy, etc, are you as aware of the clone's experience as you are of your own? If the answer is no, why would that change if the original ceases to exist? If the answer is yes, the first thing I'd want to know is _how_ exactly the information (of awareness) is possibly synchronized between hosts (presumably in realtime, at that!).
- earthboundkid 7y agoIt's really bizarre that people who don't believe in "souls" somehow think that they would be alive if a sufficiently similar mind existed somewhere. Like, okay cool, nice to know a similar mind will be out there in some computer, but that's not me, so why does that help me?
- jakeogh 7y agoMaybe our state can survive reboot... https://news.ycombinator.com/item?id=21374458 https://news.ycombinator.com/item?id=21374458
- ricree 7y agoThe wood in houses is dead and no longer able to repair wear and decay. There are known trees whose ages easily exceed a thousand years: https://en.m.wikipedia.org/wiki/List_of_oldest_trees#Individual_trees_with_verified_ages https://en.m.wikipedia.org/wiki/List_of_oldest_trees#Individ...
- hamandcheese 7y agoAlso, humans have a tendency to remove themselves from harms way. Trees, alive or dead, don’t enjoy such an advantage.
- earthboundkid 7y agoInteresting. The clonal trees aren't much like humans (disconnected, mostly in suspended animation), but other trees make a good point of comparison.
- GarrisonPrime 7y agohttps://en.wikipedia.org/wiki/Ship_of_Theseus https://en.wikipedia.org/wiki/Ship_of_Theseus
- meddlepal 7y agoIs to be human to be a fleshy meat bag? If the only thing that is actually human about us is our consciousness and we can figure out how to extract that into a digital device then I don't see why there's theoretically any time limit to our existence other than the ability to procure materials. I think this is generally where our species is heading..., we are going to continue to further blend ourselves with technology.
- monkeycantype 7y agoI like the idea of a fleet of nanobots that transparently and progressively replace defective neurons with API endpoints, until ultimately I get a chat message, "Hi MonkeyCanType, just wanted to let you know you've been 100% software for two years now. Would you like to chat about your options for printing a new body? We currently have specials on fire engines and triceratops."
- nscalf 7y agoI can buy the accident thing on a long enough time scale, even though I would imagine that emergency medicine would improve over time so it would have to be increasingly more severe of a problem. However, the “get depressed and kill yourself” argument holds no weight to me. Depression is a common thing, but such severe depression that you have suicidal tendencies is not in the cards for most humans. Humans are extremely flexible, and it really seems like some people don’t have naturally severe depressive episodes even with strong external tendencies. Beyond that, I can say that depression is often combated, in some of the less extreme cases, by recognizing it incoming and developing tools to keep yourself from spiraling. I’ve dealt with depression, and have had plenty of external things start a spiral. After many years of dealing with it, I have learned how to prevent it from getting overwhelming. I really don’t see the end of an indefinitely life occurring via suicide, assuming you’re not in isolation or alienated, or some crazy circumstance.
- nitrogen 7y agoassuming you’re not in isolation or alienated That seems like a big assumption over centuries.
- ggggtez 7y agoThis argument doesn't hold water. This assumes that depression is purely something you must be born with, and you can't get it from environmental factors. The thing is, if you really lived for hundreds of years, society would be radically different. Imagine... You can't get promoted because no one above you ever retires. You can't get an entry level job, because everyone has 200+ years experience! People struggle to work the grind until they are 65 already. But you can't retire, because your death is so far away. You need to keep grinding another 500+ years... That kind of world would likely have a lot of systemic issues with depression.
- mixmastamyk 7y agoIt’d be tough to survive on only 100 years savings.
- pferde 7y ago
- rolltiide 7y agoWe can make our minds feel whatever we want. If you never want to feel lonely or unhappy we can do that. We currently cant keep our minds from becoming dependent on an external source of what it can naturally generate.
- solveit 7y agoI would be happy to dwell on solving that problem for the next few centuries.
- chrisco255 7y agoDo you have a source on this figure? There are trees that live for thousands of years. How does their DNA preserve itself if what you say is true?
- grimgrin 7y ago> By comparing the specimens' ages and degrees of DNA degradation, the researchers calculated that DNA has a half-life of 521 years. That means that after 521 years, half of the bonds between nucleotides in the backbone of a sample would have broken; after another 521 years half of the remaining bonds would have gone; and so on. > The team predicts that even in a bone at an ideal preservation temperature of −5 ºC, effectively every bond would be destroyed after a maximum of 6.8 million years. The DNA would cease to be readable much earlier — perhaps after roughly 1.5 million years, when the remaining strands would be too short to give meaningful information. https://www.nature.com/news/dna-has-a-521-year-half-life-1.11555 https://www.nature.com/news/dna-has-a-521-year-half-life-1.1...
- aeternum 7y agoThis is assuming a dead cell. Living cells have many DNA repair mechanisms.
- samus 7y agoThat half-life probably applies if the molecular machinery inside each cell does not repair the DNA anymore. DNA repair is a skill that is as ancient as life itself, and thanks to it there are organisms (so far only plants and fungi though) that can live on for thousands of years.
- JMTQp8lwXL 7y agoMost of your cells are replaced every decade [0]. In replication, a fresh copy of DNA is created. [0]: https://www.snopes.com/fact-check/does-body-replace-itself-seven-years/ https://www.snopes.com/fact-check/does-body-replace-itself-s...
- ramraj07 7y agoMost cells, yes. All? No. Most neurons in your brain will have to last your lifetime, and IIRC some of your stem cells will have to last with the same dna strands for most of your lifetime. However if some bases in the DNA molecule get chemically degraded then error correction mechanisms should kick in and (mostly) correct them.
- viklove 7y agoIf your cells aren't replicating... what do they need DNA for?
- JMTQp8lwXL 7y agoYour DNA is read during the life of the cell for maintaining cell function, e.g, creating proteins.
- ramraj07 7y agoThe cells DNA is still the source of all information for it's functioning, when a cell has to make new protein it reads the sequence from the DNA first.
- Udo 7y agoOver long enough time scales, replication errors and base pair flips will accumulate, and it's likely these effects will become problematic way before the stated in vitro half life of 521 years. However, since we're talking about technologically enhanced life anyway, this opens the door to employing correction mechanisms that will actively repair such defects in vivo. In the end though, risks keep accumulating, both external and internal to the body. Intelligent biological life without digital backups does not seem to be the right platform for surviving time spans in excess of, say, a few hundred years.
- adrianN 7y agoThe DNA in germline cells has an unbroken chain of replication all the way back to the primordial soup.
- pixelbash 7y agoSeems like solving one would by definition solve the other? Edit, spelling