Multiple disease disorder

For years, scientists have struggled to identify specific genetic variations that put people at risk of schizophrenia. That may be because it’s eight different diseases, a study suggests.

Researchers at Washington University in St. Louis looked at the DNA of more than 4,000 people with schizophrenia, according to CNN. By matching gene variations with individual symptoms of the participants, they found several “gene clusters” that cause eight different classes of schizophrenia.

Past studies have shown that roughly 80 percent of the risk of developing schizophrenia is inherited, and that as many as 108 genes may be associated with the mental illness. This study, however, suggests that the interaction between genes may be the most important factor.

“Genes don’t operate by themselves,” wrote Dr. Robert Cloninger, one of the study’s lead authors. “They function in concert much like an orchestra.”