Team doctors specializing in genetics and neurology have discovered that mental illnesses such as schizophrenia are closely linked to mutations in the GRIN2A gene. Scientists say 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 supports the transmission of electrical signals between nerve cells and facilitates fundamental processes such as learning, memory, language and brain development.
In his article published in Molecular psychiatry, researchers have shown that the gene mutation reduces the activity of the NMDA electrical receptor, which supports neuronal communication, thus increasing the risk of developing mental disorders.
Of the 121 people tested, 85 had the GRIN2A variant, and 23 of them developed mental illness. These results show that mutation carriers are at much higher risk than those without the change. Furthermore, patients exhibited strictly psychological symptoms, which largely rule out environmental or contextual explanations.
This finding contradicts the general consensus on the polygenic origin of mental disorders. Until now, clinicians believed that these diseases resulted from the interaction of many factors, including genetic ones. This study shows 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 studies in which NMDA receptor deficiencies caused by the GRIN2A mutation were treated with the amino acid L-serine. Four patients with schizophrenia who took part in the study showed significant improvement: cessation of hallucinations, disappearance of symptoms of paranoia and improvement of behavior after treatment.
Because this study was conducted before the main study, the authors explain that it cannot yet be considered a definitive therapeutic method. However, they point out that the effectiveness of L-serine can be confirmed in a randomized, prospective, double-blind clinical trial.
Schizophrenia remains a great mystery
Schizophrenia is a mental illness that manifests itself with delusions, hallucinations, disorganized thinking and language, changes in behavior, and loss of motivation and pleasure. According to the World Health Organization (WHO), approximately 23 million people worldwide suffer from this disease, representing 0.29 percent of the world’s population. In adults, this rate increases to 0.43 percent, meaning 1 in 233 people develop it.
Specialists now understand its symptoms well and have identified the age ranges in which it usually appears. There are effective treatments and several risk factors have been identified, including genetics, neurochemistry, and external elements such as stress or drug utilize.
Still, science has not identified a single cause or fully explained the variability among those at risk. Some people develop the disease and others do not, even if both parents have been diagnosed with schizophrenia. There is also no clear strategy for preventing its occurrence.
This story first appeared in WIRED in Spanish and was translated from Spanish.