Researchers have discovered in mice how one of the few genes definitively linked to schizophrenia, called SETD1A, likely confers risk for the illness. Mice genetically engineered to lack a functioning version of the enzyme-coding gene showed abnormalities in working memory, mimicking those commonly seen in patients. Restoring the gene’s function corrected the working memory deficit and counteracting its deficiency also repaired neuronal circuit deficits in adult mice — suggesting clues for potential treatment strategies.