Is there a gene for stupid?
Maybe. Maybe not.
An article in the February 15 edition of Scientific American by Ferris Jabr reported that pharmacologist John Hepler and associates recently discovered a gene in the brains of mice that codes for a signaling protein that “significantly boosted brainpower with seemingly no negative consequences.” Jabr writes:
People have this gene, too, and it is active in the same brain area. In other words, we may have a gene in our heads that is actively making us dumber.
Hepler et al were studying the CA2 section of the hippocampus when they discovered that neurons in that area appeared to be blocked from participating in learning and memory processes when they were saturated with signaling protein RGS14.
When they bred mice who lacked the gene for RGS14 the CA2 neurons were no longer blocked and the mice exhibited some interesting differences in learning and behavior. Scientific American reports that:
The genetic tweak affected more than physiology—it changed how the mice performed on memory tests, too. The experimenters presented two identical objects to knockout mice, which lacked the RGS14 gene, and to normal mice. Four hours and again 24 hours later, the researchers switched one of the objects with a new object. The knockout mice spent far more time exploring the new object than the normal mice did, indicating that the altered rodents had a better memory for distinguishing familiar and strange objects. Knockout mice also learned to navigate a water maze and locate a submerged platform faster than normal mice did. The scientists observed no detriments from removing the RGS14 gene.
“Why would we have a gene that makes us dumber?” asks Serena Dudek, a neuroscientist at the National Institute of Environmental Health Sciences and a co-author of the study, which was published in the September issue of the Proceedings of the National Academy of Sciences USA. “We don’t know. But if the gene is conserved by natural selection, there must be some reason. Intuitively, it seems there should be a downside to having this gene knocked out, but we haven’t found it so far. It may be that these mice are hallucinating, and you just can’t tell.”
And this is where I get frustrated that I don’t have unlimited access to journal articles (or an unlimited budget to buy it with) because based on what they’re saying here it sounds to me that while the gene may have something to do with spatial learning, it might also have evolved as a safety mechanism controlling neophobia – not stupidity.
I suppose that one might be able to test this by looking at the action of CA2 in young animals during different stages of development when neophobia typically ebbs and wanes, but since mice reach maturity within weeks of being born, I’m not sure they’d be viable candidates for this.
Either way, I’m sad to say that I don’t think they’ve discovered a genetic cure for stupidity.