Five major psychiatric disorders — autism, ADHD, bipolar disorder, depression and schizophrenia — have genetic links, scientists say.
Previously, psychiatric disorders were diagnosed based chiefly on behavior rather than biology, Fox News wrote.
For instance, symptoms of hyperactivity and inattentiveness might be diagnosed as attention deficit-hyperactivity disorder, while mood swings might suggest bipolar disorder.
However, the Psychiatric Genomics Consortium analysis of the genomes of more than 61,000 people — including 33,000 with one of the five disorders and 28,000 without — suggested that genetic variations may be key in the development of psychiatric disorders.
According to UPI, the researchers "found four regions of the genetic code where variation was linked to all five disorders."
Lead researcher Dr. Jordan Smoller, a psychiatry professor at Massachusetts General Hospital, told CBS:
"There were several regions of the genome, several variations that seemed to increase the risk for all five. It's important to realize, of course, that this is a small part of the genetic component of these disorders, but it points to a shared biology."
The research indicated that while the onset of psychiatric disorders could be attributed to factors including environment, experience and trauma, genetics could identify heightened risk.
UPI cited Dr. Bruce Cuthbert of the National Institute on Mental Health, which funded the research, as saying that regardless, doctors and researchers were still learning how to diagnose mental illnesses with the precision of physical illnesses.
And Nick Craddock, professor of psychiatry at Cardiff University, said:
"This is a scientific method that helps understand what is going wrong in the brain, the chemicals, the brains systems, that are important in illness."