First Single Gene Cause Found for Mental Illness

The field of mental health genetics has witnessed a major development with the identification of the GRIN2A gene as a singular cause of schizophrenia and other psychiatric disorders. This breakthrough research, published in Molecular Psychiatry, directly challenges the long-standing belief that conditions like schizophrenia result solely from the interplay of multiple genetic and environmental factors (polygenic causes).

Professor Johannes Lemke, Director of the Institute of Human Genetics at the University of Leipzig Medical Centre, led the German study. Professor Lemke stated that the current findings indicate that GRIN2A is the "first known gene that, on its own, can cause a mental illness," distinguishing it from the polygenic models previously assumed.

Researchers analyzed data from 121 individuals carrying genetic alterations in GRIN2A. A striking finding was that these specific gene changes were associated not only with schizophrenia but also with other mental illnesses that developed in childhood or adolescence, preceding the typical adult onset of schizophrenia. The team also noted that some participants displayed only psychiatric symptoms, despite GRIN2A changes usually being linked to conditions like epilepsy or intellectual disability.

The GRIN2A gene is crucial for regulating the electrical excitability of nerve cells. Variants found in the gene led to reduced activity of the NMDA receptor, a key molecule involved in brain signaling, learning, memory, and cognition. This disruption provides a concrete genetic target for intervention.

Collaborating with Dr. Steffen Syrbe, the clinicians demonstrated therapeutic potential: in an initial treatment series, patients experienced marked improvements in psychiatric symptoms after receiving L-serine. L-serine is a dietary supplement that functions by activating the NMDA receptor, suggesting that treatments targeting this underlying biological cause are possible.

This discovery holds substantial implications for public health, potentially allowing for earlier screening and intervention before the full manifestation of symptoms, thereby improving prognosis. Moreover, associating mental illness with identifiable genetic changes can help reduce stigma.

Experts emphasize, however, that while a major stride, schizophrenia remains complex. The study involved a relatively small sample size, and many cases of schizophrenia continue to involve polygenic and non-genetic factors. Genetic testing is not yet recommended for routine clinical use pending further validation and ethical review.

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🔖 Sources

Scientists discover first gene proven to directly cause mental illness

" Breakthrough Study Identifies GRIN2A as a Single Gene Cause of Schizophrenia and Mental Illness"

Scientists Identify First-Ever Single Gene That Can Directly Cause Mental Illness

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Keywords: First Single Gene Cause Mental Illness

First Single Gene Cause Mental Illness

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