For the First Time, Mutations in a Single Gene Have Been Linked to Mental Illness

"A team of physicians specializing in genetics and neurology discovered that mental illnesses such as schizophrenia are closely linked to mutations in the GRIN2A gene. The scientists mantain that identifying this genetic risk factor opens up the possibility of designing preventive therapies in the future. The GRIN2A gene regulates communication between neurons by producing the GluN2A protein. When functioning optimally, it promotes the transmission of electrical signals between nerve cells and facilitates essential processes such as learning, memory, language, and brain development."

"In their article, published in Molecular Psychiatry, the researchers demonstrated that the gene mutation reduces the activity of the NMDA electrical receptor, which aids in neuronal communication, thereby increasing the risk of developing mental disorders. Of the 121 individuals studied, 85 had a GRIN2A variant and 23 of them developed a mental illness. These results show that carriers of the mutation have a significantly higher risk than those without variations."

"The finding contradicts the general consensus on the polygenic origin of mental disorders. Until now, clinicians have considered that these diseases arise from the interaction of multiple factors, including genetic ones. This study demonstrates for the first time that a mutation in a single gene can decisively influence the development of a mental disorder. The report also cites previous research that treated NMDA receptor deficiency, caused by the GRIN2A mutation, with L-serine, an amino acid."

Mutations in the GRIN2A gene impair production of the GluN2A protein and reduce NMDA receptor activity, weakening neuronal electrical communication critical for learning, memory, language, and brain development. In a cohort of 121 individuals, 85 carried GRIN2A variants and 23 of those developed a mental illness, indicating significantly higher risk among carriers. Affected patients presented strictly psychiatric symptoms, minimizing environmental explanations. The findings show that a single-gene mutation can decisively influence mental disorder onset, challenging polygenic models. Prior treatment of NMDA deficiency with L-serine produced marked symptomatic improvements in four schizophrenia patients, suggesting therapeutic potential.

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