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Acquired Characteristics May Be Inheritable

A story from a week or so back in Technology Review describes research coming to the surprising conclusion that Jean-Baptiste Lamarck may have been right — that acquired characteristics can be passed on to offspring, at least in rodents. Lamarck's ideas have been controversial for 200 years, and dismissed in mainstream scientific thinking for nearly that long. "In Feig's study, mice genetically engineered to have memory problems were raised in an enriched environment — given toys, exercise, and social interaction — for two weeks during adolescence. The animals' memory improved... The mice were then returned to normal conditions, where they grew up and had offspring. This next generation of mice also had better memory, despite having the genetic defect and never having been exposed to the enriched environment."

16 of 242 comments (clear)

  1. Interesting... by drosboro · · Score: 5, Informative

    Lamarck is one of those guys who's name is generally synonymous with bad science (he's about as villified as Darwin is deified). I'm actually a bit (pleasantly) surprised that someone would invest the time into this sort of study.

    That being said, the article is rather short in one important area: a suggested mechanism for this sort of inheritance. Without that, it's bound to be mired in controversy for some time.

    1. Re:Interesting... by MoellerPlesset2 · · Score: 5, Informative

      Lamarck is one of those guys who's name is generally synonymous with bad science (he's about as villified as Darwin is deified).

      What? I've heard Larmarck's evolutionary ideas ridiculed but villified?
      He wasn't that unscientific. He was just wrong.

      Or are you thinking of Lysenko? Now that particular advocate of inherited-acquired-characteristics was indeed a villain, a lousy scientist and a political tool.

    2. Re:Interesting... by cryptoluddite · · Score: 5, Insightful

      Article doesn't say what interactions the adult mice had with their offspring. The benefit may have just been passed to the next generation through regular learning, modeling, etc.

      I don't know about lab mice, but rat packs have a pretty complicated social structure (for example nominating food tasters to try new sources of food) so I'd bet that mice can teach their young a lot more than researchers might suppose.

    3. Re:Interesting... by Kandenshi · · Score: 5, Insightful

      Here's my personal suggested mechanism.

      Enriched environments have long been known to make mice 'happier' in addition to being better at solving various tests, and having larger brains, etc. This stress-reducing effect has been known to be maintained long after the rats are removed from the enriched environment.

      The change in the mother rats should fully be expected to be partially shared with the pups. The womb is not a completely separate environment that just happens to exist inside the mother, her experiences shape what sort of chemicals(beneficial or detrimental) are delivered to the baby.

      A healthier, less stressed out mother is likely to nurture her babies properly while they're in utero, and uterine environment that's not bathed in stress hormones is generally a preferable one for the baby's neurological development.
      TFA also mentions that an opposite effect occurs, where highly stressed mothers had babies that then also abused their pups tend to have pups that themselves are poorer mothers. They don't mention if problem solving tests were given to these rats, but I'd fully expect that they'd show deficits in tests of memory and intelligence.

      The researchers in the article say that this is a completely shocking discovery, I'd be shocked if it didn't happen. The stress response affects not only the mother, but also the baby, and those changes can be noticed in their later lives. Quel surprise.

    4. Re:Interesting... by drosboro · · Score: 5, Informative

      Actually, I've just taken a peek at the original article in J. Neuroscience, as posted in the comments below.

      The interesting thing is that this seems to be passed on at embryogenesis - so it's quite distinct from learning. It's also quite distinct from other epigenetic inheritance studies, which have demonstrated that some of mom's behaviour can result in changes in the offspring's tissues. If this is in fact happening at the embryo stage, it is a whole different pathway.

    5. Re:Interesting... by williamhb · · Score: 4, Insightful

      That being said, the article is rather short in one important area: a suggested mechanism for this sort of inheritance. Without that, it's bound to be mired in controversy for some time.

      This is an unfortunate shortcoming of science at the moment. A tested result is rejected until there is a suggested mechanism; as soon as a mechanism is suggested, it is all too often treated as "true" even if the mechanism itself has never been experimentally tested at all but was just plucked out of the air. The one that instantly springs to mind is the 2005 result that being cold can after all make you susceptible to catching a cold. The paper is reasonable and itself admits that its "suggested mechanism" (that capillaries in the nose constrict, reducing access by the immune system) was not itself tested by the authors, but was just an idea they came up with when their actual experiment -- do people sitting around with their feet in bowls of icy water catch colds more often -- gave a positive result. Nonetheless, that mechanism very quickly started getting bandied around as if it were gospel.

    6. Re:Interesting... by ceoyoyo · · Score: 4, Informative

      Yes, it does. The article says that the changes are still evident even when the pups are raised by control rats, NOT their mother.

      It also says the change is not permanent - it only lasts a few months. I didn't notice any mention of whether the mother rat still functions at a high level when she's pregnant. If she does, the change could be due to the environment in utero, which would be consistent with the effect fading over time.

    7. Re:Interesting... by im_thatoneguy · · Score: 5, Insightful

      How is that a shortcoming of science?

      1) The researches found a result.
      2) Proposed a possible mechanism.
      3) Stated the mechanism was untested and might just be bullshit they cooked up at the pub.

      4) People misreport guess of researchers as "Fact!" ...
      6) "Shortcoming of science!" (and profit?)

      It's sort of like saying that the urban legand "People think we only use 10% of our brain even though research has shown this to be almost certainly false." is a shortcoming of science.

      People talk. People like to have "all the answers". The problem is with gossip not science. 'Science' hasn't ruled on the subject yet. The official stance of 'science' is that the mechanism is unknown.

      Just as 'science' has only found that mouse mothers subjected to certain conditions can pass along the effects to their children even after the conditions have ceased. The mechanism should be discovered before any other conclusions can be reached. The summary is attempting to assign far more consequence to the study than study can provide. The shortcoming is with vague and speculative reporting not science. /rant

    8. Re:Interesting... by TapeCutter · · Score: 4, Insightful

      "This is an unfortunate shortcoming of science at the moment."

      I agree with most of your post but disagree with your conclusion.

      Contrary to the GP's claim there is no requirement in science for a "suggested mechanisim", the results of the experiment are far more important than the explaination. For example, nobody has yet explained gravity but few doubt it exists and that we can acurately predict it's behaviour via models.

      However it is common practice for papers to offer (clearly labelled) speculation in the hope that "someone else" will look for evidence and cite your paper if they find it. A failure to understand the difference between clearly labeled speculation and repeatable experimental results is definitely a "shortcoming" but it is not a "shortcoming of science". Worse still the "shortcoming" of which you speak is often indistingushable from willfull ignorance.

      "A tested result is rejected until there is a suggested mechanism" - This is simply false.

      IMHO the "unfortunate shortcoming of science" is the apparent inability of it's philosophy to rate a mention in high school science classes. This is not due to a lack of trying, see: Sagan, Dawkins and Randi. My own SPECULATION as to why is it so, is that most people ( including the majority of educators ) simply want certainty and cannot accept a philosophy that shuns it, so the philosophy part is ignored and science becomes a library of factiods that are discovered via inspiration, rather than found via critical thinking.

      --
      And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
    9. Re:Interesting... by Abreu · · Score: 4, Informative

      So does he work for the discovery institute?

      Close, he was employed by Joseph Stalin

      --
      No sig for the moment.
  2. Actual article by Anonymous Coward · · Score: 5, Informative

    Here's the actual article.

  3. Histone modifications by Rand310 · · Score: 5, Informative

    We're just learning that Histone/DNA modifications can be inherited.

    Histones (the spools around which DNA is stored) tell when the DNA source code should be 'active' vs 'inactive'. And these histones have a huge data space in the form of possible modifications (methylation, acetylation, etc.).

    When DNA is replicated, these histones too are replicated at the same time. And they seem to be replicated in a semiconserved manner similar to DNA (half go to 'old' strand, half go to 'new' strand). And that there is a whole series of touring-like proteins that can 'read' 'write' or 'erase' these modifications.

    If these modifications are made during an organism's life, they can be inherited by offspring.

    Not only is the code being copied, but the 'marks' that tell which/when/where to read the code at any given time/condition too can be passed down. And that these marks can be written in real time rather than waiting for mutations in the code itself.

    There was a recent study that XO females who inherited the X from their father had markedly different dispositions than those who inherited the X from their mother. DNA modification that is unique to how the male or female deal with their own X chromosome could be being passed down to offspring.

  4. Wait, how does it get passed? by Richard.Tao · · Score: 4, Insightful

    Females have all the eggs made before they're born, so how could the genetic material in them be affect by the conditions that the mother grew up in? Sperm DNA seems like it could be modified by the father according to living conditions, but it seems odd to think that environmental information in the brain would be passed down to the testes and such... It seems more plausible to think it's just the mice had a better mother.

  5. Re:Finally... by RuBLed · · Score: 4, Funny

    Interesting eh? So how did it explained religion?

    Is it where the first ones get all the good stuff and the offsprings only get to dream/think about it? Well I could understand that if the scenario was giving dozens of virgins to one guy, the rest would only dream about it. In that case it would be a supply and demand problem, not an inherited one. (or in our case as /.ers, it might not even matter if there's an abundance in the supply anyway.)

  6. Not a joke... by chill · · Score: 4, Interesting

    In Soviet Russia, Lamarckism as interpreted by Lysenko in agriculture, was the state mandated approach and genetics was essentially outlawed until the 1960s. Geneticists were fired from jobs, sent to work camps, prison or just executed.

    --
    Learning HOW to think is more important than learning WHAT to think.
  7. Females aren't born with all their eggs by PIPBoy3000 · · Score: 4, Informative

    This was a common misconception until recently. You can read about it here.