An anonymous reader writes "The world's largest brain study to date, with a team of more than 200 scientists from 100 institutions worldwide collaborated to map the human genes that boost or sabotage the brain's resistance to a variety of mental illnesses and Alzheimer's disease. The study also uncovered new genes that may explain individual differences in brain size and intelligence. From the article: 'Following a brain study on an unprecedented scale, an international collaboration has now managed to tease out a single gene that does have a measurable effect on intelligence. But the effect – although measurable – is small: the gene alters IQ by just 1.29 points. According to some researchers, that essentially proves that intelligence relies on the action of a multitude of genes after all.'"