She noted that all five of the conditions tackled in the study can share certain clinical features and symptoms, including variation in mood, mental impairments, and even psychosis.
"Therefore, the question is whether the identified shared genetic risk factors are related to the diseases or to the shared clinical symptoms," Redei said. "Shared genetic contribution can identify some key regulators in the brain, and can also help to find new drug targets," she said.
Simon Rego, director of psychology training at Montefiore Medical Center at the Albert Einstein College of Medicine in New York City, agreed that the findings are "an important next step" in understanding mental illness.
As more gene studies are conducted and analyzed, scientists will "be in a better place to identify shared cause of psychiatric disorders at a molecular level," he said. "Ultimately, [this could] generate new models for drug interventions and possibly even prevention."
For more information on mental disorders, visit the U.S. National Institute of Mental Health.
SOURCES: Jordan Smoller, M.D., professor of psychiatry, Harvard Medical School, associate vice chair, department of psychiatry, Massachusetts General Hospital, Boston; Simon Rego, Psy.D., director, psychology training, Montefiore Medical Center/Albert Einstein College of Medicine, New York City; Alessandro Serretti, M.D., Ph.D., Psychiatry Institute, University of Bologna, Italy; Eva Redei, Ph.D., David Lawrence Stein Professor of Psychiatry, Feinberg School of Medicine Northwestern University, Chicago; Feb. 28, 2013, The Lancet, online
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