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Did a Genome Copying Mistake Lead To Human Intelligence?
A new study suggests that the sophistication of the human brain may be due to a mistake in cell division long ago. From the article: "A copyediting error appears to be responsible for critical features of the human brain that distinguish us from our closest primate kin, new research finds.
When tested out in mice, researchers found this 'error' caused the rodents' brain cells to move into place faster and enabled more connections between brain cells."
The subtitle also has a stylistic difference from the article text--it has no comma or other punctuation. Every sentence of comparable length in the rest of the article (around 15 of them) has a comma, colon, dash, etc., with only one exception, supporting my "someone else wrote the title and subtitle" theory, perhaps someone more interested in page views than providing information.
This is why I love Slashdot - we'd rather spend ages analysing a secondary popular science article to death than talking about the interesting findings of the primary research! The author and/or editor deserve a break for trying to engage the attention of a general audience about a piece of significant work, and succeed in presenting the key points in relatively non-technical language. Both 'mistake' and 'error' are in any case used quite frequently by biologists when discussing mutations - a quick pubmed search will find many examples in the scientific literature (e.g. http://www.ncbi.nlm.nih.gov/pubmed/14616055 - this does not imply that the DNA polymerase is intelligent!).
Speaking of 'mistakes', this research discovered an interesting error in the human genome reference sequence. It turns out that the duplication event was previously obscured by 'mis-assembly' of the closely related copied sequences (the SRGAP2 gene was copied so recently in evolutionary terms that the copies hadn't diverged enough to be easily distinguishable). The researchers did some of their own sequencing using DNA from a 'hydatidiform mole' ( http://en.wikipedia.org/wiki/Hydatidiform_mole ), a non-viable pregnancy that only contains genetic material from the father - the lack of confounding allelic variation makes it easier to get clear cut results.