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Biotech Medicine Science

Ancient Virus DNA Discovery Could Be a Breakthrough In How Diseases Are Treated 53

concertina226 (2447056) writes "Understanding how retroviruses are passed down through our DNA could be the key to helping researchers re-programme normal cells to become stem cells for treating diseases. Researchers from Canada and Singapore have discovered that the ancient viruses which entered our ancestors' genomes thousands of years ago have altered the way our cells behave; the material left by dead viruses in our cells is the answer. 1,000 copies of one particular class of retroviruses, known as the human endogenous retrovirus HERV-H, is still in our genome, and while the HERV-H retrovirus DNA is dead and cannot replicate itself, it continues to send out messages telling the embryonic stem cell how to become other cells in the body, and this is what makes the cells pluripotent."
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Ancient Virus DNA Discovery Could Be a Breakthrough In How Diseases Are Treated

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  • Not "thousands" (Score:5, Insightful)

    by bargainsale ( 1038112 ) on Monday March 31, 2014 @03:57PM (#46625325)
    "which entered our ancestors' genomes thousands of years ago"

    Millions. One might hope that errors of three orders of magnitude would be uncommon on Slashdot.
    • Re: (Score:1, Insightful)

      by Anonymous Coward

      "which entered our ancestors' genomes thousands of years ago"

      Millions. One might hope that errors of three orders of magnitude would be uncommon on Slashdot.

      While I agree, it technically does not say how many thousands.

      • From the National Geographic article:

        More than 1,000 copies of HERV-H litter the human genome. The DNA sequences are unique to humans and great apes, apparently invading primates less than 20 million years ago, said evolutionary geneticist Cedric Feschotte of the University of Utah, who did not take part in this research.

        What I would like to know is what did mammals, reptiles, and other organisms do before this.

    • Re: (Score:3, Informative)

      by Opportunist ( 166417 )

      More likely billions. If that "dead" virus DNA gives our cells the ability to specialize, they're pretty much the requirement for complex organisms that aren't just a collection of identical cells. And that in turn means that pretty much everything but single cell organism (and groups thereof) need that DNA sequence.

      • by bargainsale ( 1038112 ) on Monday March 31, 2014 @04:09PM (#46625451)
        Exactly so. The actual article says "millions" though. Perhaps the submitter himself didn't read TFA?
        • I'm thinking the submitter is so busy submitting articles that he doesn't have time to read them, or even to comment on anything else.
        • Good lord, you don't submitters actually write their own summaries, do you?

          No, it's your basic Slashdot cut-and-paste job. At least one other person has copy-pasted the "thousands" version in a post so it looks like the article writer thought they were writing for rednecks [youtube.com], but have since been corrected.

      • Re:Not "thousands" (Score:4, Interesting)

        by Samantha Wright ( 1324923 ) on Monday March 31, 2014 @04:15PM (#46625501) Homepage Journal
        The oldest known animals only go back 665 million years. It's relatively unlikely that our cell differentiation mechanisms are much older than that, so "billions" is a bit overambitious.
        • by Anonymous Coward

          Sorry, but thank you for playing:

          The first evidence of multicellularity is from cyanobacteria-like organisms that lived between 3 and 3.5 billion years ago.

          https://en.wikipedia.org/wiki/Multicellular_organism

          • Oh, don't worry, I double-checked Wikipedia too. :) If those were truly multicellular (and the evidence is inconclusive as to whether or not some of them were even cells) then it's very likely they developed it independently. Continuing to quote Wikipedia:

            Multicellularity has evolved independently at least 46 times,

            ...and that's without discussing pluripotency, which is the ability to differentiate various kinds of cells. It's very unlikely that Metazoa separated from Protozoa more than a billion years ago.

            (Better luck next round, hero.)

          • by ceoyoyo ( 59147 )

            Read your link more carefully. True multicellular organisms have differentiated cells and must somehow figure out how to create more of themselves, as an organism. That's where pluripotent stem cells come in. The very early forms of "multicellular" life, like those cyanobacteria, are more like colonies of cooperating individuals.

      • Re:Not "thousands" (Score:4, Insightful)

        by ColdWetDog ( 752185 ) on Monday March 31, 2014 @05:53PM (#46626405) Homepage

        No,they're not required. That's the funny part. There are primates which do a wonderful job of going from fertilized egg to organism without the viral DNA. It's just that the viral DNA is very active in a class of stem cells and not active in other cells. It was thought that all of this 'junk DNA' - which includes most of the incorporated retrovirus DNA - didn't do anything.

        Now they know it does something. Only in stem cells. That's weird. And fun. But it's not clear that this is useful or will cure cancer or allow you to get a date.

        As usual, it's interesting science hyped beyond measure.

        • They just should have asked some computer scientists. There's plenty of stuff in a computer that looks useless once booting is finished.

          • There's plenty of stuff in a computer that looks useless once booting is finished.

            Like, say, Windows? //rim shot

        • by TheCarp ( 96830 )

          > Now they know it does something. Only in stem cells. That's weird. And fun

          So it is a boot sector infection.

      • That assumes that these genes are the ONLY way for cells to specialize and that it could never happen without them. How often are questions of genetics THAT simple? More likely these genes turned out to be helpful to a process which was already occuring and that is why evolution preserved them.

      • by ceoyoyo ( 59147 )

        Not billions. Complex multicellular life likely formed around 600 million years ago. Before that it was all unicellular. It would be a nice story if a virus combining with a eukaryotic cell sparked multicellular life, as prokaryotic cells combined to produce eukaryotic cells.

    • by Anonymous Coward

      Well technically, a million is a thousand thousands, so they are correct, it's just that it's a lot of thousands. But from what I can tell, HERV-H entered our ancestor species genome 30 million years ago, so they're actually four orders of magnitude out.

    • "which entered our ancestors' genomes thousands of years ago"
      Millions. One might hope that errors of three orders of magnitude would be uncommon on Slashdot.

      There are 2 different articles linked here. They are very similar but differ slightly.

      From the first Article:

      More than 1,000 copies of HERV-H litter the human genome. The DNA sequences are unique to humans and great apes, apparently invading primates less than 20 million years ago, said evolutionary geneticist Cedric Feschotte of the University of Utah, who did not take part in this research.

      So the sequences invaded PRIMATES "less than" 20 million years ago.

      From the second

      Researchers from Canada and Singapore have discovered that the ancient viruses which entered our ancestors' genomes thousands of years ago have altered the way our cells behave; the material left by dead viruses in our cells is the answer.

      And here it says "Thousands" which are actually probably in the hundreds of thousands.

      • It now says:

        Researchers from Canada and Singapore have discovered that the ancient viruses which entered our ancestors' genomes millions of years ago...

    • Millions ARE thousands! Many of them!

      Have our ancestors carried these genes for millions of years? By most counts our species is only about 1 million years old so I would believe it if someone told me we carried genes that were only 100s of thousands of years old. Then again, we could have inheritted this from our non-homosapien ancestors so I would believe milliions of years too. Maybe I should stfu and rtfu?

  • by Alan Kennington ( 33546 ) on Monday March 31, 2014 @04:16PM (#46625511) Homepage

    There's too much that sounds wrong to me in this story.

    1,000 copies of one particular class of retroviruses, known as the human endogenous retrovirus HERV-H, is still in our genome, and while the HERV-H retrovirus DNA is dead and cannot replicate itself, it continues to send out messages telling the embryonic stem cell how to become other cells in the body, and this is what makes the cells pluripotent.

    Maybe the 1000 copies could be correct, but that sounds a bit too high. But the last phrase and this is what makes the cells pluripotent sounds quite wrong. Does this mean that pluripotency didn't happen before this virus got into the genome? This would have to be at least 600 million years ago then. I note that the date in Australia is now 1 April 2014 already.

    • by Altus ( 1034 ) on Monday March 31, 2014 @04:21PM (#46625567) Homepage

      I think we are looking at a bad summary as usually the articles dateline is March 31st, but thank you for reminding me to get off of the internet for the next ~48 hours.

    • For a long time, scientists thought that this retrovirus DNA was just junk sitting around in the cells.

      I have always said, "Junk DNA isn't." From time to time, articles like this prove me correct.

      Having said that, stem cells must specialize in order for an embryo to develop into an adult. The "human endogenous retrovirus" can't be responsible for the specilization of stem cells, because at some point in history, there was a first time that a human was infected by this retrovirus; and somehow, that human's parents managed to develop normally.

      Also, my cat was once an embryo, and stem cell specilization took

      • Humans haven't existed for 20 million years.

      • Of the many millions of primates infected with retroviruses like this, some of those infections replaced egg or sperm DNA that was previously responsible for the specialization of stem cells. When the replacement DNA didn't also drive specialization, I suspect the offspring was naturally aborted (or grew as a tumor until it killed its mother).

        Sometimes though, the virus mutation that replaced the DNA also happened to be able to create the same or similar encoding. Voila, this virus is more successful, bec

  • Hierarchical evolution (AKA "tree of life") may be technically wrong. Viruses and other microbes have probably crossed genes among many species and perhaps even phylum (especially early on when wiring was more similar).

    It may have even sped up evolution because "good ideas" could cross tree boundaries such that a given branch didn't have to re-invent everything from scratch. Branch A may have the best eyes and branch B have the best immune system. If genes from A and B can be intermixed among two species th

    • by Firethorn ( 177587 ) on Monday March 31, 2014 @05:35PM (#46626229) Homepage Journal

      This could pose a problem for evolution in court because one can no longer claim "evolution predicts a tree of life".

      Not sure why. It's moving past where Evolution was taught when I was in High School, but in college and since this sort of stuff started popping up, first noticed with Bacteria, which turn out to share DNA quite often.

      Indeed, I believe that the more complex methods of DNA transfer existing only weakens young-earth creationist arguments. Leaves them with less wiggle-room in trying to refute Evolution.

      Remember, the core theory of 'evolution' doesn't require only the sexual method of DNA sharing, though that's perhaps the easiest to explain to kids. Bacteria sharing chunks of DNA coding for antibiotic resistance is getting into advanced territory.

      Finding out that 'life' is more of a messy ball with lots of weird interconnects is more in line with what you'd expect from evolution than some sort of 'neat' process controlled by some sort of designer.

    • by ceoyoyo ( 59147 )

      I think you've got it backwards. The weaker creationist/intelligent designers claim that microevolution happens but "types" can never change into other "types". Swapping genetic material between widely separated branches is one way that could happen.

    • by dryeo ( 100693 )

      What's the problem. Trees often have branches grafted to themselves and even branches grafted to different trees, across species as well. This just makes the tree of life more realistic, branches grafting to other branches equals species exchanging genes. Just need a good arborist or biologist to explain it to the court.

  • by John Bokma ( 834313 ) on Monday March 31, 2014 @05:42PM (#46626293) Homepage
    Darwin's Radio by Greg Bear. I read it recently, and can recommend it.
  • 200 types of cells making up the human body, and this "junk" tells them how to be themselves, and when.

    "Not to worry though" - that's reassuring.

    • 200 types of cells making up the human body, and this "junk" tells them how to be themselves, and when.

      Fascinating. I guessed it would be much more than 200.

      • by ceoyoyo ( 59147 )

        Depends on how you define a "type." You can make reasonable arguments for as few as 3. Or as many as you want.

  • What's the problem, just add acid!
  • We should be careful in attributing an effect of viruses observed on human embryonic stem cells to an important role on human embryogenesis and evolution. ES cells are grown in tissue culture conditions, which are related to embryonic conditions, but are not the same. Without knowing the mechanism whereby HERV-H affects ES cell self renewal, it seems just as likely that it is due to some artifact of cell culture as it is due to an effect of evolution.

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