Study Suggests Schizophrenia Is Actually Several Genetically Distinct Disorders

By John Lugo

Jonathan Bailey, NHGRI

According to a new Washington University study, schizophrenia isn’t a single disease, but eight distinct disorders caused by multiple genes working together.

The research group focused on finding a stronger association between genes and schizophrenia, after previous research mainly centered on single genes and failed to find a strong correlation.

“In the past, scientists had been looking for associations between individual genes and schizophrenia,” says Dragan Svrakic, one of the study’s investigators and a professor of psychiatry at Washington University. “When one study would identify an association, no one else could replicate it. What was missing was the idea that these genes don’t act independently. They work in concert to disrupt the brain’s structure and function, and that results in the illness.”

After comparing the genomes of 4,200 people with schizophrenia and 3,800 people without it, the researchers identified groups of interacting gene clusters that contribute to eight different types of schizophrenia. The group hopes that with this new information, it will be possible to target treatments to individual patients.

Robert Cloninger, a Washington University psychiatric geneticist and one of the study’s senior investigators, also believes this approach could help scientists better understand other complex diseases.

“People have been looking at genes to get a better handle on heart disease, hypertension, and diabetes, and it’s been a real disappointment,” Cloninger says. “Most of the variability in the severity of disease has not been explained, but we were able to find that different sets of genetic variations were leading to distinct clinical syndromes. So I think this really could change the way people approach understanding the causes of complex diseases.”