ADHD Shares Links with Four Mental Disorders

Scientists have identified genetic links between five major psychiatric disorders -- ADHD, autism, bipolar disorder, depression, and schizophrenia.

The study, published in The Lancet, showed that there were specific genetic variants that influence a range of childhood and adult-onset psychiatric disorders, says Jordan W. Smoller, M.D., one of the lead researchers in the study and a psychiatry professor at Massachusetts General Hospital.

There was some evidence that there are shared links among disorders -- some families are affected by multiple kinds of disorders -- but this was the first time that researchers were able to see specific DNA variations.

An interesting finding from the study showed that so-called “calcium channels” in the brain affected how brain cells communicated. “This seemed to be associated with all of these disorders, so it raises the possibility that treatments that target those channels might have broad effects,” says Smoller.

If you have a family member with one of these disorders, it doesn’t mean you will develop the disorder, adds Smoller. “While we know that all psychiatric disorders seem to run in families to a degree, we also know that genes are not destiny.”

The findings could change the way we define and diagnose these disorders, based on the biological causes. “Some of the disorders we think of as clinically distinct have more of a relationship than we might have thought,” says Smoller.