The right loves genetic explanations for poverty or mental illness. But science fingers society.
Oliver James in The Guardian:
When the map of the human genome was presented to the world in 2001, psychiatrists had high hopes for it. Itemising all our genes would surely provide molecular evidence that the main cause of mental illness was genetic – something psychiatrists had long believed. Drug companies were wetting their lips at the prospect of massive profits from unique potions for every idiosyncrasy.
But a decade later, unnoticed by the media, the human genome project has not delivered what the psychiatrists hoped: we now know that genes play little part in why one sibling, social class or ethnic group is more likely to suffer mental health problems than another.
This result had been predicted by Craig Venter, one of the key researchers on the project. When the map was published, he said that because we only have about 25,000 genes psychological differences could not be much determined by them. “Our environments are critical,” he concluded. And, after only a few years of extensive genome searching, even the most convinced geneticists began to publicly admit that there are no individual genes for the vast majority of mental health problems. In 2009 Professor Robert Plomin, a leading behavioural geneticist, wrote that the evidence had proved that “genetic effects are much smaller than previously considered: the largest effects account for only 1% of quantitative traits”. However, he believed that all was not lost. Complex combinations of genes might hold the key. So far, this has not been shown, nor is it likely to be.
More here.