Many distinct psychiatric diseases share a common genetic structure, according to new research by scientists at Massachusetts General Hospital (MGH) and the Psychiatric Genomics Consortium, an international team of investigators. Psychiatric disorders affect more than 25 percent of the population in a given year. In the largest-ever study of its kind, published in the journal Cell, researchers identified more than 100 genetic variants that affect the risk for more than one mental health condition.
A gene is made up of segments of DNA; an alteration in the DNA sequence produces a gene variant, which can increase or decrease the risk for disease. Many individual gene variants that affect the risk for specific psychiatric disorders have been identified. However, genes are often pleiotropic, meaning they produce multiple effects in the body.
Identifying gene variants that influence the risk for more than one psychiatric disorder is an important step toward improving the diagnosis and treatment of these conditions, says the study’s senior author, Jordan W. Smoller, MD, ScD, director of MGH’s Psychiatric and Neurodevelopmental Genetics Unit and a professor of Psychiatry at Harvard Medical School (HMS). “Understanding how specific genetic variations may contribute to a broad spectrum of illnesses can tell us something about the degree to which these disorders may have a shared biology,” says Smoller.