Researchers, for the first time, have pinpointed a genetic hotspot that confers risk for both bipolar disorder and depression. People with either of these mood disorders were significantly more likely to have risk versions of genes at this site than healthy controls. One of the genes, which codes for part of a cell’s machinery that tells genes when to turn on and off, was also found to be over-expressed in the executive hub of bipolar patients’ brains, making it a prime suspect. The results add to mounting evidence that major mental disorders overlap at the molecular level.