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After Death, Hundreds of Genes Spring Back to Life

Posted by EditorDavid on from the walking-dead dept.

Two surprising studies reveal new information about what genes do after death. Slashdot reader gurps_npc writes: You think your body stops after death, but up to two days later certain genes may turn on and start doing stuff for another two days before they give up the ghost. We are all zombies for up to four days after death.
Gizmodo reports that in fact "hundreds" of genes apparently spring back to life. "[P]revious work on human cadavers demonstrated that some genes remain active after death, but we had no idea as to the extent of this strange phenomenon."

16 of 62 comments (clear)

  1. Its simple by bazmail · · Score: 3, Interesting

    The death of suppression genes allow some of the surpressed to activate post mortem. But to no end. They die soon.

    1. Re:Its simple by RyanFenton · · Score: 5, Interesting

      A large portion of our (and virtually all other life) is partially composed of virus-inserted code.

      To a virus, life isn't really a thing to begin with, only DNA interactions, with rare opportunities to copy.

      From that perspective, death of the host body just means it's bacteria party time, and even if 99% of organelles used to copy are kaput, almost all viruses are bacteria-predators anyway. So, hiding away in human DNA for a few hundred generations or whatever is just a distraction from getting to the (ambiguous) goal of a bacteria to infect.

      So, now that they're not suppressed, some random virus code passively sends a request to the organelles to write a copy of themselves for the 83rd billionth time, and this time don't get their message scrambled. All this happens trillions of times, infects perhaps millions of bacteria that manage to escape, which spread off into the world to keep the messy process going.

      Niches for DNA code are massively multidimensional, and even though the possibility space for success is outrageously sparse, the life that lives in the outer reaches of possiblity doesn't have be intelligent to know it's a bad idea, and so spreads where we can't imagine. Things like life that only has the chance to reproduce every few hundred years (using another life form's mechanisms to keep their DNA active in the meantime), or has to jump between 3 species in order to continue a full reproduction cycle.

      Heck, the only reason we can move around and talk and stuff is because some odd other microlife got mixed in with an ancestors cells to become mitocondria. With that, we can live away from immediate energy sources, and use sugars. To this day, bacteria are constantly mixing DNA with eachother, getting into the oddest combinations, with some help from viruses, who get everyone else involved in the party.

      And from a microscopic perspective, we're mostly mobile apartments for bacteria, that protect the bacteria/helpful viruses we like from the bacteria/viruses that tend to wreck the apartment. Fortunately, most bacteria are boring tenants, and most viruses only target bacteria.

      Ryan Fenton

    2. Re:Its simple by quantaman · · Score: 2, Insightful

      A large portion of our (and virtually all other life) is partially composed of virus-inserted code.

      To a virus, life isn't really a thing to begin with, only DNA interactions, with rare opportunities to copy.

      From that perspective, death of the host body just means it's bacteria party time, and even if 99% of organelles used to copy are kaput, almost all viruses are bacteria-predators anyway. So, hiding away in human DNA for a few hundred generations or whatever is just a distraction from getting to the (ambiguous) goal of a bacteria to infect.

      [...]

      Niches for DNA code are massively multidimensional, and even though the possibility space for success is outrageously sparse, the life that lives in the outer reaches of possiblity doesn't have be intelligent to know it's a bad idea, and so spreads where we can't imagine. Things like life that only has the chance to reproduce every few hundred years (using another life form's mechanisms to keep their DNA active in the meantime), or has to jump between 3 species in order to continue a full reproduction cycle.

      I'm not sure this story holds up. The moment a virus gene is inserted into our genome its reproductive cycle becomes tied to ours. Even if some virus DNA could escape our cells and infect bacteria post-mortem they'd just become ordinary viruses.

      The only way for genes to retain function is for that function to be subject to natural selection. But as long as those virus genes are trapped in a human DNA strand the only way for them to propagate is through people, and the moment they escaped they'd be tied to that new organism. There's nothing in human reproduction that ensures that transplanted virus strands stay functional viruses.

      A gene going through a multi-species reproductive cycle sounds interesting, but I'm really skeptical it's happening. At least in humans that cross-species jump is just too difficult.

      --
      I stole this Sig
  2. Re:last chance to spread genes by Opportunist · · Score: 2

    Somehow doubtful. When talking about some corpse getting stiff, this is usually not what is meant.

    --
    We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
  3. Click bait? by turbidostato · · Score: 4, Interesting

    What's that article beside click-bait?

    "previous work on human cadavers demonstrated that some genes remain active after death" What does mean "remain active" with regards to genes? For all that I know (and I own a Biology major) genes just "stay there" (more or less) for RNA to make use of them so, what this does mean? That supressing factors, as they are supressing no more after death, allow for some genes to be expressed after death? What a surprise! I don't mean the details not to be worthnoting as I'm not aware too many time/money has been thrown towards that target but that the general assertion is of little surprise. We already knew death is not an event but a process (despite all legal interest in the contrary).

    1. Re:Click bait? by Wuhao · · Score: 5, Funny

      For all that I know (and I own a Biology major)

      Owning people is morally wrong. I really think you should let that poor student go.

    2. Re:Click bait? by turbidostato · · Score: 5, Funny

      I am a CEO, you insensitive clod!

  4. Re:last chance to spread genes by lucm · · Score: 2

    the opposite would be even more impressive.

    --
    lucm, indeed.
  5. Your computer changes after you turn it off! by shess · · Score: 4, Funny

    Sometimes, after you turn your computer off, activity does not immediately cease! There are various thermal adjustments which continue to happen for hours after power down! Sometimes random electrical signals can be sent for no apparent reason!

    Seriously, the human body is a complicated chemical plant without centralized control. Some stuff keeps happening. Other stuff doesn't. Big deal.

    1. Re:Your computer changes after you turn it off! by BlackPignouf · · Score: 3, Funny

      The solution is obvious, ask Poettering to integrate a systemd process to terminate every gene that isn't properly killed.

    2. Re:Your computer changes after you turn it off! by KiloByte · · Score: 2

      And he would require everyone who dies the old way to adjust to his change.

      --
      The creatures outside looked from Alt-Right to Antifa; but already it was impossible to say which was which.
  6. Re:last chance to spread genes by Anonymous Coward · · Score: 2, Funny

    Citation needed (for adult bedtime horror story time)

  7. Pre-print article by drunken_boxer777 · · Score: 2

    Here is the pre-print article:

    http://www.biorxiv.org/content...

  8. Random stuff by duckintheface · · Score: 2

    As the cellular systems decay, there is probably lots of random stuff going on. Normal feedback pathways don't work. It's impossible to predict. But there is not really a reasonable mechanism for evolutionary selection for these processes so even the ones that make sense (like stress reaction or immune stimulation) are just vestigial precesses. Not interesting.

    --
    "He took a duck in the face at 250 knots." -- William Gibson, Pattern Recognition
    1. Re:Random stuff by sjames · · Score: 4, Interesting

      I can imagine one (not saying it is at work here). If some residual activity reduced the chances of harmful (to the still living) bacteria taking hold, it might confer a slight advantage to the still living relatives of the deceased.

  9. Nobody yet? OK. by Hognoxious · · Score: 2, Funny

    Things unexpectedly activating is usually due to a virus that goes by the common name of systemd.

    --
    Confucius say, "Find worm in apple - bad. Find half a worm - worse."