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Scientists Discover How To Track Natural Errors In DNA Replication

Posted by samzenpus on from the points-of-failure dept.

BarbaraHudson writes Researchers figured out how to label and keep track of new pieces of DNA, and learned to follow the enzyme responsible for copying those pieces. Their research focused on enzymes called polymerases. These enzymes create small regions in DNA that act as scaffolds for the copied DNA. Scientists assumed that the body deletes the scaffolds containing errors, or mutations, and the standard computer models supported this theory. However, the actual research showed that about 1.5 percent of those erroneous scaffolds are left over, trapped within the DNA. After running models, scientists now believe they can track how DNA replicates and find the most likely areas where these scaffolds with errors turn up. The erroneous scaffolds usually appear close to genetic switches, those regions that turn on when genes activate. The mutations damage the switch, which results in genetic disease, as well as increasing the likelihood of cancer.

19 comments

  1. Does this explain... by Anonymous Coward · · Score: 0, Troll

    how Republicans were first created? They have a pretty serious error inherent to their kind.

    1. Re: Does this explain... by Anonymous Coward · · Score: 0

      http://youtu.be/RWpU8sX10_4

    2. Re: Does this explain... by Anonymous Coward · · Score: 0

      Do you have a link that works? You know damn well that the only videos that play on that shithole site are the ads. The content doesn't work. It hasn't for years, but that doesn't stop you old people from still trying to use it. That is proof that you are old and irrelevant like a Republican. Maybe you are one of them.

  2. It's amazing... by smaddox · · Score: 3, Insightful

    It's amazing that we're able to learn so much (regardless of how little it really is) about something so mind-bogglingly complicated. Biological processes make quantum mechanics look like child's play.

    1. Re:It's amazing... by BarbaraHudson · · Score: 1

      Look at the medical advances over the last 30 years, and it's kind of hard to imagine where we're going to be in another 30.

      --
      "Transparent" is a shit show that trades on every stereotype going. A man in drag is NOT a transsexual.
    2. Re:It's amazing... by aliquis · · Score: 0

      When look at how far we'd develop if we all were religious fundamentalists.

      That's what scares me in Europe and in "my country" Sweden the most.

      People should be free to call out the nasty destructive bullshit for what it is.

      How much of value has people in say Saudi Arabia produced / capita vs the people of the US in the last 50 years?

    3. Re:It's amazing... by Anonymous Coward · · Score: 0

      It's amazing that we're able to learn so much (regardless of how little it really is) about something so mind-bogglingly complicated. Biological processes make quantum mechanics look like child's play.

      what the fuck are you talking about? all biological processes are governed on a smaller scale by atomic and quantum processes which are not at all well understood, otherwise we would be able to predict how those biological processes worked by calculation

  3. Ha! by The+Wild+Norseman · · Score: 1

    Scientists Discover How To Track Natural Errors In DNA Replication

    "Scientists"?! Yeah, "scientists" from the NSA, maybe!!!! Those fuckers will stop at NOTHING to track every damn little thing and now this?! What did poor little DNA ever do to you, you fascist bastards?!

    --
    "A government is a body of people usually -- notably -- ungoverned." -Shepherd Book
  4. Problem for Evolution by labnet · · Score: 1

    Isn't this a problem for Evolution proponents.
    Evolution requires that beneficial DNA mutations win out over non-beneficial.

    Lets say DNA is like a self replicating VM. The VM has built in error correction but occasionally a copy error occurs. The premise of evolution, is this copy error is occasionally beneficial and the non beneficial errors eventually die out, but the spectrum of copy errors can cause vastly different outcomes. Sometimes a copy error may change an eye color, or cause a miscarriage.
    The question is, does the rate of beneficial mutations outweigh the rate of non-beneficial so the NEW functionality is created and functional entropy is halted?
    My pragmatic side says, If I changed random bytes in a VM, I wouldn't eventually get a facial recognition system, I'd get slowly decaying VM.
     

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    46137
    1. Re:Problem for Evolution by sjames · · Score: 1

      The part you're missing is selection. The harmful mutations either fail to reproduce altogether or they reproduce at a lower rate than the good ones. Actual experiments show that you can actually randomly mutate a program and if you have a good selection function, you can actually evolve new functionality.

      The catch is that the evolution tends to 'find' really odd solutions.

    2. Re:Problem for Evolution by Anonymous Coward · · Score: 1

      http://www.nature.com/nature/journal/v485/n7396/full/nature10995.html

      "Evidence of non-random mutation rates suggests an evolutionary risk management strategy"

      http://www.the-scientist.com/?articles.view/articleNo/27910/title/Are-mutations-truly-random-/

      "Do genetic mutations really occur at random spots along the genome, as researchers have long supposed? Maybe not, according to a study published online today (January 13) in Proceedings of the Royal Society B, which proposes a mechanism for how new mutations might preferentially form around existing ones."

      The general consensus has been that there are "hot spots" that experience more DNA mutations than other areas. These usually have markers, such as "pseudo-genes", where the genetic code is more likely to be altered. It has been assumed by some that some time around 65 million years ago, current species all simultaneously experienced a kind of locking in of genetic code so that we don't have much change in those last 65 million years, compared to say the Cambrian Explosion very early on.

      Hope that helps a bit with your line of thinking.

      Ultimately, one big issue isn't with rate of mutation in a certain area, but something that has caused studies to be done about the rate of simultaneous mutation. If we breed a sexually reproducing organism that has experienced a mutation back with the general population that does not share that mutation, it tends to "breed out" that mutation. Hybrids are formed and then the trait is basically lost.

      We see this in White Tigers, in that it isn't actually albinism, but a certain trait that appears that creates the white coloration. If those white tigers are bred back with the general tiger population, the trait is lost, so we have to inbreed the tigers. This has been considered inhumane and banned in most countries.

      We've also see media icon Neil Tyson tweet about "which came first, the chicken or the egg" about which he said that something that was "not quite a chicken" came before. Several people pointed out that something that is a significant variation from another species will either not be able to produce viable offspring with the existing population, or will have that odd trait bred out of a line.

      And that's why research has been done to try to find a reason for multiple simultaneous mutations to occur in order to explain mutations that are necessarily complex enough that they would not survive breeding back with the general population. It's all part of the ongoing "irreducible complexity" arguments that have led into some wild theories being claimed as "proven" when they have not. One instance of this is in the Dover trials with Professor Behe, where the lawyers not only used straw-man arguments against Behe, but also made claims that "co-opting" genetic material was generally accepted as fact, when it is far from it.

      http://www.discovery.org/a/14251
      "The NCSE, Judge Jones, and Citation Bluffs About the Origin of New Functional Genetic Information" - Casey Luskin, Evolution News & Views, March 2, 2010

    3. Re:Problem for Evolution by BarbaraHudson · · Score: 2

      Of course, there's also the fact that each of us harbors about 60 mutations - stuff we didn't inherit from either parent.

      --
      "Transparent" is a shit show that trades on every stereotype going. A man in drag is NOT a transsexual.
    4. Re:Problem for Evolution by Anonymous Coward · · Score: 0

      This isn't "a problem for Evolution proponents". This is, in fact, required for Evolution.

      Your message suggests that for Evolution to be successful, that "the rate of beneficial mutations must outweigh the rate of non-beneficial so the NEW functionality is created and functional entropy is halted".

      However, successful evolution does not require this. If you think about it, it's easy to see why: you are neglecting the effects of natural selection in Evolution.

      From an evolutionary standpoint, it would not matter even if 99% of mutations turned out to be invariably fatal, as long as there was 1% which did not and was beneficial, provided that the species reproduces easily enough that it can absorb this much loss (plus other losses such as due to predation or accidental death) without resulting in a downward trend in population over time. As long as the species population is stable or growing overall, the individuals with damaging mutations will be less likely to survive and procreate, while those with beneficial mutations will not only survive, but will successfully procreate at a rate higher than the unmutated individuals (presumably because they are less likely to die before procreating). Over time, the individuals with beneficial mutations will tend to dominate the population due to their increased probability of successfully procreating versus the unmutated or damagingly mutated ones.

      Regarding your example: cellular life is not like a computer program (VM or otherwise). A typical computer program has a single processor which is doing all of the work, and if that processor gets stopped somehow (e.g. sent into an endless loop or triggers a segmentation fault), then the whole thing is stopped cold. Cellular life, on the other hand, is like a huge number of individual programs all executing in parallel, such that if one program goes nuts, other adjacent programs aren't stopped from proceeding anyway. A better metaphor would be a cellular automata such as John Conway's "Game of Life".

      In your example, if there was some overall reason why programs which were more successful at facial recognition were more likely to be able to get reproduced (and possibly mutated), while ones that were less successful were more likely to be terminated, then over time, the population of programs would be gradually dominated by ones that that were more successful at this task. Given billions of processors running for billions of years in such a scenario, eventually you will get one or more programs which perform adequately at facial recognition (for some definition of "adequately"), and how adequately the best ones perform will tend to increase over time. It may take a long time, but eventual success is pretty much mathematically mandated by virtue of the fact that it becomes increasingly improbable for it not to have happened yet as time increases.

      In general, Evolution requires three things:
      1) A population of "things" which are capable of reproduction and death,
      2) Reproduction is imperfect in that sometimes something substantially "like" but not exactly "the same as" the original occurs.
      3) Individuals subject to some criteria are more likely to reproduce themselves than others (typically by avoiding death before reproduction).

      If you have these things, then eventually, over time, the population will tend to consist of those individuals which are the best fit to the criteria. This applies not just to living objects, but also to other things which obey the above postulates. For instance, consider how cell phones evolve:

      1) They reproduce (someone makes a new model very like an old one, if the old one is selling well) and die (if nobody likes it enough to buy it).
      2) They are mutated (manufacturers try to make changes to appeal to consumers. Some are good ideas, while others are not.)
      3) The consumers apply various criteria (battery life, size, etc.) to decide which cell phones to buy. Less successful ones don't get bought.

      Similar arguments could be made for cell phone

    5. Re:Problem for Evolution by labnet · · Score: 1

      Those are interesting points.

      I read 'Darwins Black Box' by Behe many years ago, and thought he made good rational arguments about irreducible complexity.

      When a genetic mutation occurs, there will be a continuum of effect, from new feature to no effect to death.
      Natural selection will only have a certain forcing effect that is weighted to the 'death' end of the scale.

      The problem I have with evolution, is the vast majority of any random mutation will be non beneficial and that this process will happen faster than natural selection can remove these defects from the population.

      --
      46137
    6. Re: Problem for Evolution by Anonymous Coward · · Score: 0

      Look at the modern bacteria genome, you need a population with size > threshold for genomes to purge the junk.

    7. Re:Problem for Evolution by Anonymous Coward · · Score: 0

      boxcar2d.com

  5. Re:Netcraft confirms, DNA is found in semen by Anonymous Coward · · Score: 0

    [X] I have used SLASHDOT BETA to find a sex partner

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