5 Most Common Mental Illnesses Share the Same Genes

A National Institute of Mental Health (NIMH) funded study published online in Lancet reveals that the five most common disorders—autism, attention deficit hyperactivity disorder, bipolar disease, schizophrenia, and major depression — all share similar genetic components.

"These disorders that we thought of as quite different may not have such sharp boundaries," said Dr. Jordan W. Smoller of Massachusetts General Hospital, one of the lead study authors.

The results suggest that a rethink in how these disorders are defined might be in order. Rather than focusing on symptoms, which can be attributed to one or more disorder, physicians could one day start to rely on specific gene mutations or biologic pathways to make a formal diagnosis.

And it also could lead to better treatments, said Dr. Bruce Cuthbert, director of the NIMH’s Division of Adult Translational Research and Treatment Development. "We are finally starting to make inroads where we have actual physiological mechanisms that we can target," he said. "We can really start to understand the biology instead of having to guess at it."