Scientists have identified GRIN2A as the first gene capable on its own of causing a mental illness, according to a new international study. Researchers found that specific mutations in the gene were linked to early-onset schizophrenia and other psychiatric disorders. “Our current findings indicate that GRIN2A is the first known gene that, on its own, can cause a mental illness,” said co-lead author Johannes Lemke. Evidence shows symptoms often appear in childhood or adolescence.
The study examined 121 individuals with likely disease-causing variants in GRIN2A and found that 25 had conditions such as mood, anxiety, psychotic, personality, or eating disorders. Nearly all carried a non-functional “null” variant. Some patients treated with L-serine reported improved psychiatric symptoms, including remission from hallucinations and paranoid episodes. The authors say genetic testing could enhance diagnosis and guide personalized care.