Scientists in North Carolina say they have identified a gene that affects IQ, a finding that, if confirmed, would be a significant step toward understanding the genetic basis for intelligence.
The new research could also have ethical implications because the effect of the gene appears to be quite dramatic: The scientists say that males who inherit a particular version of the gene have, on average, an IQ that is 20 points lower than males who don't.
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The researchers studied about 300 children with an average age of 10. The children, all Caucasian, came from six counties in the Cleveland area. As a group, males '” but not females '” who had the variant gene had IQ scores about 20 points lower than males who didn't.

This made me laugh. Quick, without a tissue sample, list ten men that have this gene.