• Gene Duplication May Be the Cause of Human Brains

    File under my favorite category “things that creationists say can’t happen and end up do happening”. A recent research article has shown that an incomplete gene duplication is likely responsible for humans having larger and more effective brains.

    ARHGAP11B is a gene that is an incomplete duplication of the gene ARHGAP11A. The P11A gene produces a GTPase, a member of a family of proteins that are involved in a variety of areas of the cell. The authors were looking for genes that were involved in the development of the human brain. Why was the cortex, the outer layer of the brain, larger in humans and other primates than in mice?

    First they had to identify the stem cells that become cortical cells. They did this by using fluorescent tags to the stem cells to see which cells became which type of tissue. Then they examined the cells that made up the cortex to see which genes were active in the cortex forming cells.

    There were 56 genes that were in humans, but not mice. Of those, ARHGAP11B, was the most active. As I mentioned, this gene is known to have formed from a gene duplication event (which neatly defeats all the creationist arguments regarding gene duplication). (And as soon as I find a copy of the reference I’ll post it.)

    The interesting thing is that that gene only exists in humans, Denisovans, and Neandertals. This is a human specific gene duplication event.

    But it gets even more interesting. The authors placed that gene into the mouse genome to see what would happen. Remember that this is an incomplete copy of a totally different gene.

    Mrs. Brisby meets Nicodemus. The Secret of NIMH. copyright Sullivan Bluth Studios

    The number of cortex stem cells doubled and their brains sometimes developed folds. These folds are not present in mice normally, but are present in primates. The gene also causes more stem cells that divide more frequently. Resulting in a larger than normal brain.

    I’ll let the authors speak about the result that

    emphasizes the likelihood that this gene was indeed important during mammalian evolution for the design of a new brain, bigger and more complex,

    So, there we go an incomplete gene duplication results in thicker cortexes, with more folding. The authors clearly state that they think there are more genes waiting to be discovered, but this is a pretty astounding result.

    It is very likely that a total accident is one of the reasons humans evolved into intelligent creatures.

    Category: EvolutionfeaturedGeneticsResearchScience


    Article by: Smilodon's Retreat

    • nicky

      Wonder what your habitual troll, Rex T., will possibly come up with now?

      • SmilodonsRetreat

        In all likely hood, he will ignore the topic for a few months, then bring it up again when he thinks we’ve forgotten about this experiment.

        More probably, he’ll say that because the gene duplication was “incomplete” it means that evolution still only produces bad things or something illogical like that. Somedays, i agree with Douglas Adams, some times I think coming out of the trees was a bad idea.

        But then I think of all we’ve accomplished, in spite of people like Rex. Hypocritical people who reject science, while at the same time benefiting from it. Then I think, no one else listens to him. Scientists keep on sciencing… in spite of creationists telling them what science can’t do. And then we get experiments like this, which show those creationists that they really are science stoppers and just flat out wrong.

      • RexTugwell

        Hey gents. I’m not sure how this experiment negatively affects my side. Maybe you could enlighten me.

        • SmilodonsRetreat

          Because it shows that the claims of the creationists are wrong. Gene duplication happens. It does generate novel features. Very, very novel in this case.

          All you have to do is find evidence that an intelligence did this. And you’d be correct. Of course, that’s all the ID team has had to do all along and since it’s the one thing that they know that they can’t do, they specifically say it’s not needed.

    • Jeff Grigg

      might be one of “all the creationist arguments regarding gene duplication”

      • SmilodonsRetreat

        Wow that’s pretty impressive, conflating gene duplication with chromosome duplication. Huge difference.

        “Statistical evaluation of the predictions of the gene duplication theory does not appear to be favourable to it. For example, the theory predicts a positive correlation between organismal complexity and gene number, genome size and/or chromosome number.”

        Hmmm…. no citation for that one. I wonder why. It appears to be a made up fact.

        Evo-Devo… that’s pretty funny. Using a evolutionary process to reject another evolutionary process. Again, this clown is making like either gene duplication is correct or evo-devo is correct. That’s certainly not the case… as both are known to occur.

        The Functional Challenge. Ohno, mentioned in this article, was working 30 years PRIOR to 2001. That was almost 50 years ago. Wow. That’s some industrial grade manipulation there. But what’s funny is that the article he links to explicitly rejects his own claims. He also continues to conflate gene duplication and chromosome duplication.

        The rest is just a mishmash of lies, half-truths, and total irrelevancies.

        But yes, thanks for that link. I see where a couple of people I argue with have gotten their ideas from now.

    • RexTugwell

      Hmmm. I don’t know. Nicky, what do you think about Dr. Retreat’s conclusions?

      • nicky

        I think that gene duplication is an important mechanism, our tri-colour vision from the general mammal bi-colour vision appears to be a good example.
        However, I do disagree with Ohno that it is the *only* mechanism. Apart from point mutations, deletions and inversions, there is symbiosis.
        The advent of the eukaryotic cell being he most important example.

        • SmilodonsRetreat

          There’s at least five methods for new genes to appear and they are not mutually exclusive.

    • RexTugwell

      Oh! Looky there. Uncommon Descent is reporting the same study on its website. Smiley, why don’t you mozey on over there and tell everyone why they should be worried about such research.

      Here’s my favorite pull quote from the article which I don’t find your report:
      (The researchers did not check to see if the mice actually got smarter,
      though that is a potential avenue of future research, Florio said).

      I’d also be interested in whether the mice would be able to thrive and reproduce.
      Keep up the good work, Smilodon.

      • SmilodonsRetreat

        Oh looky, a goal post shift. How unexpected…

        So, the entire premise of that article is based on intelligence, when the authors specifically said that they weren’t looking at intelligence. How interesting. A textbook example of a goal-post shift… or maybe begging the question.

        They totally don’t address the actual issues I mentioned. That the gene is a result of a gene duplication that resulted in a novel (new, unusual, never seen before) effect.

        Amazing how they totally glossed over that… no, not amazing… typical.

        They aren’t worried about anything, because they don’t care. Just like you don’t care. Anything that they think will support their views.

        This is a fantastic example of evolution that ID proponents say can’t happen. But it did. All there is to it.

        • RexTugwell

          Yeah, we’ve seen novel effects before. Four-winged fruit flies, eyes growing out of legs, legs growing out of heads. No goal post shift, just the air being let out of your balloon.

          • SmilodonsRetreat

            Nope, it’s a goal post shift. The point is not to measure intelligence. The point is where the unique trait of thicker cerebral cortex and the folding pattern comes from.

            You whining about intelligence is the same as whining to Donald Prothero (a paleontologist) that he didn’t adequately explain epigenetics.

            You’re purposefully moving the point away from the results because they make your ideas look bad.

            But, OK, tell you what. You use ID to explain exactly how the human brain developed. In at least equivalent detail to what this paper provides.

            • RexTugwell

              Sorry to break this to you, Smiley but no one I know denies gene duplication. I’m starting to think you’re just manufacturing claims that not even ID proponents don’t believe.
              – denial of gene duplication
              – no beneficial mutations
              – can determine the benefit or detriment of a mutation by only looking at the DNA

              All straw men. What’s up with that?

            • SmilodonsRetreat

              Nope. You might want to have a talk with your fellow ID proponents then. I continue to be amazed that you don’t even know what your “side” thinks about certain subjects.

              Of course, those ideas on those subjects can change at a moments notice.

              Luskin sure thinks that gene duplications can’t be useful. http://www.evolutionnews.org/2011/01/a_fishy_story_about_antifreeze043141.html

              And Behe suggested as much in his and Snooks paper. Of course Bozorgmehr thinks that gene duplciation in constrained.

              With all of the evidence against them, they still think that gene duplications can’t increase information or whatever, since that is demonstrably untrue, then THEY are the ones with the problem.

              You can probably find some ID proponent who exclaims the virtues of gene duplication to the heavens. And that’s fine.

              It really highlights the basic problem with Intelligent Design. It’s not even a coherent notion yet. The leaders (and the proponents online) don’t even have a good idea of what it does, how it does, what it means, and who the designer is (hint, it’s not god because god doesn’t exist).

              As far as the last, YOU have determined whether a mutation is beneficial or detrimental just by looking at it. You think that sickle cell anemia is detrimental. Of course, like most ID proponents, you won’t take a stand on a position about it, you’ll wiffle and waffle so that you can say “I never said that’.

              Honestly, I’m getting seriously tired of you and other ID people. You don’t actually do anything useful. You just misrepresent, misdirect, change the subject etc.

              For example, you haven’t brought up your claims about intelligence in several posts now. Do you accept that you claims are wrong or just ignore it because you won’t admit to being wrong.

              When we first started this dialogue years ago, I thought that you might be willing to see the evidence for yourself, but you don’t care about evidence. You just care about your belief system.

              So now, here’s your chance…. defend ID. Go for it. State the premises of ID and defend them. I don’t think you actually will (or can), but try. Show us the alternative to evolution and the evidence for it. Show how evolution is wrong and ID is right. Go ahead. We both know you won’t though.

            • RexTugwell

              I have been defending ID and you’ve been defending the creative power of Darwinian evolution. Based on past exchanges with you like your review of Darwin’s Doubt and misrepresentations of the ID side and laughable papers that require a suspension of critical thinking, I’d say thinks are going quite well for me.

              Shall I provide yet another parameter of fine-tuning?

            • RexTugwell

              BTW, you’re homework for tonight is to read (notice how I didn’t say re-read) chaps 10 and 11 in Darwin’s Doubt.

            • SmilodonsRetreat

              Do you think that there will be any true statements in it?

            • SmilodonsRetreat

              1) Meyer is a liar. You should accept that.

              2) Suspension of critical does sound exactly like you.

              3) Even if every possible metric could not vary by more than 0.000000000000000000001% it’s still not evidence for god.

          • nicky

            I’m sure these mice were as least as clever as you (no I mean after the duplication, I’m not trying to insult here), but alas they did not get the language genes to show off. 🙂

    • Smilodon, you may be interested in another page at creation.com. Notice the sentence just before the references: “The diversity we see today could be partly due to a range of frogs surviving outside Noah’s Ark—the wide geographic distribution today of so many frog families suggests this.”


      Outside the ark? Hmm, if frogs, or anything else, could survive and did survive without being on the ark, then what was the point of the ark? And what about the wide geographic distribution of lots of other biological entities on Earth? Apparently a lot of things survived “outside of Noah’s Ark”. It’s pretty funny to see creationists say things that contradict their biblical fairy tales.