🚨 Mental illness has just been traced to a single gene for the first time.
For decades, mental illnesses like schizophrenia were believed to arise from the complex interplay of numerous genes and environmental factors. Now, a groundbreaking study has identified the first single gene capable of triggering psychiatric disorders entirely on its own.
Researchers have pinpointed GRIN2A as this rare culprit. In some individuals carrying specific damaging variants of the gene, severe psychiatric conditions – including schizophrenia-like symptoms – can emerge as early as childhood, rather than the typical onset in late adolescence or early adulthood.
Perhaps most strikingly, several patients exhibited purely psychiatric symptoms with no trace of the seizures, intellectual disability, or developmental delays that were previously considered hallmarks of GRIN2A-related disorders. This finding dramatically reframes our understanding of how genetic mutations can lead to mental illness.
GRIN2A encodes part of the brain’s NMDA receptors, which are critical for communication between neurons. When the gene is faulty, it throws this signaling system into disarray.
Encouragingly, some affected individuals showed clear improvement when given L-serine, an inexpensive amino acid supplement that helps restore NMDA receptor function.
Though still in its early stages, the discovery raises the prospect of genuinely precision-based treatments for certain forms of mental illness – therapies that correct the root genetic cause rather than merely managing symptoms.
The results come from the world’s largest registry of GRIN2A patients and represent more than ten years of close collaboration between neurologists, psychiatrists, and geneticists across the globe.
["GRIN2A null variants confer a high risk for early-onset schizophrenia and other mental disorders and potentially enable precision therapy." Molecular Psychiatry, 2025]