The Misunderstood Gene

Where did people get the idea that traits like intelligence could be determined by individual genes? That's what University of Oxford neuropsychology professor Dorothy Bishop wants to know. Writing for the Guardian's science blog, Bishop wonders where we got the idea that people's mental and physical traits can be predicted from their genes. Some genes are all-or-nothing predictors of certain traits, such as Huntington's disease, Bishop says. But most times, the interactions between genes are much more complex. Height, for instance, is determined by several different genes, each of which adds or lessens a person's height. Certain genes that influence traits like obesity, can be counteracted by a person's behavior and environment. "This means that we get a very different impression of the strength of genetic influences on a trait if we look at the impact of a person's whole genome, compared with looking at individual genes in isolation," Bishop says. The idea that you can test for a musicality gene in your child, or whether or not you have an optimism gene "is just plain wrong," she adds.