CALGARY -- A joint study of pediatric saliva has uncovered genetic risk factors for obsessive-compulsive disorder (OCD) that could potentially lead to earlier diagnosis and improved treatment.

The spit study, conducted collaboratively by research teams at the University of Calgary and The Hospital for Sick Children (SickKids) in Toronto, identified a genetic variant within the PTPRD gene commonly found in those at greater risk of OCD traits.

"Our group made the first finding of a genome-wide significant risk gene relevant to childhood OCD," explained Dr. Paul Arnold, MD, PhD, co-principal investigator, a professor and director of The Mathison Centre for Mental Health Research & Education at the Cumming School of Medicine, in a statement. "We’ve known that OCD runs in families, but we hadn’t identified and validated specific genetic risks of OCD symptoms in children and youth until now."

Saliva samples from more than 5,000 children and youth were studied and compared to the survey responses of participants using the Toronto Obsessive-Compulsive Scale developed by Dr. Arnold and the SickKids team.

While millions of genetic variants appeared in the samples, a specific variant was discovered in those determined to be at risk.

Dr, Jennifer Crosbie, a clinical psychologist at SickKids, says identifying the variant could pave the way to improving assessment and treatment.

"OCD can present very differently and at various ages in each individual, adding to the challenge of treatment and diagnosis," said Crosbie. "Studies like this one are an important step towards developing precision medicine approaches for mental health."

The study's findings are available at Translational Psychiatry.