4 ms·

This is a MUCH better explanation: https://www.ncbi.nlm.nih.gov/pubmed/25459141 https://www.ncbi.nlm.nih.gov/pubmed/25459141 Killing off the misbehaving cells

by nonbel 7y ago

This is a MUCH better explanation: https://www.ncbi.nlm.nih.gov/pubmed/25459141 https://www.ncbi.nlm.nih.gov/pubmed/25459141 Killing off the misbehaving cells is an obvious solution but this must also shorten the organisms lifespan via organ failure. You only get so many divisions from the zygote before a cell line must be killed off, put into senescence, or it starts malfunctioning due to accumulated mutations (~60). A good solution produces as many differentiated functional cells as possible while minimizing divisions from the zygote. Really, this article shows a fundamental misunderstanding of how our bodies work.

eloff 7y ago
So just waving away the insane technology leaps required, if we had a digital copy of our DNA we could theoretically create pristine new stem cells and inject them into our bodies as needed to replace aging cells. You might make such a master copy at birth, or more likely in such a world, you're conceived from the master copy which your parents carefully edited before deciding to have you. Fundamentally we could live a really long time in the far future, which is maybe closer to us today than we are to 0 A.D.
- nonbel 7y ago
  The "master copy" would be at conception. Even after a few divisions it is unlikely any of the cells carry the exact same DNA. And just because you made it from zygote to birth does not mean your master copy was "pristine". But yeah, if you could somehow replace your tissue stem cells in situ with ones that are closer to the original state it would generally allow your body to continue functioning for much longer. I mean some of those mutations could be beneficial to your particular environment too, but in general... Yeah.
  - neetdeth 7y ago
    You don’t have any single non-degraded copy but you do have billions of degraded copies. Assuming errors are non-correlated, one ought to be able to reconstruct the original sequence given enough of them. The idea would be to use some far-future technology to enable a kind of DNA repair that cells themselves can’t do, using non-local information from other cells in the organism.
    - nonbel 7y ago
      Most mutations are probably large scale chromosomal missegregation, etc where huge chunks get moved around or duplicated/deleted rather than just replacing/removing/adding a single nucleotide. From what I have read something like that happens about once every 10 divisions per cell line. So I think that could be more difficult than you expect.
      - eloff 7y ago
        I think the same statistical methods apply to cancel the noise.
        nonbel 7y ago
        I doubt it, it isn't like the average is going to correspond to the actual original sequence.
  - bohm 7y ago
    It's worth pointing out that YC startup foreverlabs.com does freeze your stem cells for precisely that reason.
    - eloff 7y ago
      Interesting! Not a bad idea given there will likely be more stem cell based treatments available in the future. The cost benefit analysis seems to make sense to me.

by nonbel 7y ago

eloff 7y ago

So just waving away the insane technology leaps required, if we had a digital copy of our DNA we could theoretically create pristine new stem cells and inject them into our bodies as needed to replace aging cells. You might make such a master copy at birth, or more likely in such a world, you're conceived from the master copy which your parents carefully edited before deciding to have you. Fundamentally we could live a really long time in the far future, which is maybe closer to us today than we are to 0 A.D.

nonbel 7y ago
The "master copy" would be at conception. Even after a few divisions it is unlikely any of the cells carry the exact same DNA. And just because you made it from zygote to birth does not mean your master copy was "pristine". But yeah, if you could somehow replace your tissue stem cells in situ with ones that are closer to the original state it would generally allow your body to continue functioning for much longer. I mean some of those mutations could be beneficial to your particular environment too, but in general... Yeah.
- neetdeth 7y ago
  You don’t have any single non-degraded copy but you do have billions of degraded copies. Assuming errors are non-correlated, one ought to be able to reconstruct the original sequence given enough of them. The idea would be to use some far-future technology to enable a kind of DNA repair that cells themselves can’t do, using non-local information from other cells in the organism.
  - nonbel 7y ago
    Most mutations are probably large scale chromosomal missegregation, etc where huge chunks get moved around or duplicated/deleted rather than just replacing/removing/adding a single nucleotide. From what I have read something like that happens about once every 10 divisions per cell line. So I think that could be more difficult than you expect.
    - eloff 7y ago
      I think the same statistical methods apply to cancel the noise.
      - nonbel 7y ago
        I doubt it, it isn't like the average is going to correspond to the actual original sequence.
- bohm 7y ago
  It's worth pointing out that YC startup foreverlabs.com does freeze your stem cells for precisely that reason.
  - eloff 7y ago
    Interesting! Not a bad idea given there will likely be more stem cell based treatments available in the future. The cost benefit analysis seems to make sense to me.