Genetics is rarely as straightforward as a single gene driving a lone health outcome. But a new study has uncovered what could be a rare exception. Changes to just one gene, called GRIN2A , have now been tied to psychiatric symptoms, including early-onset schizophrenia . "Our current findings indicate that GRIN2A is the first known gene that, on its own, can cause a mental illness," says co-lead author Johannes Lemke, a geneticist from Leipzig University in Germany. Mental health disorders,