Study finds 36 genes tied to OCD and tic disorders

At Rutgers, DNA samples donated by families have sat in a repository for as long as 20 years. Modern sequencing has now put them to work: a Rutgers-led international collaboration identified 36 genes tied to obsessive-compulsive disorder (OCD) and chronic tic disorders, including Tourette syndrome.

The study analyzed DNA from nearly 4,000 people diagnosed with one or both conditions. Researchers used whole-exome sequencing, which reads the protein-making sections of genes, and compared affected individuals with their parents and controls. In some cases, mutations appeared in a child but in neither parent, giving researchers clues about genes that may contribute to the disorders.

Many of the genes are shared by OCD and chronic tic disorders. That fits the clinical picture: both conditions often begin in childhood and can occur together in the same people and families. The genes also overlap with pathways previously linked to autism and schizophrenia, suggesting that different psychiatric conditions can involve related disruptions in brain development and communication.

The mechanism is still being mapped. The identified genes appear to affect neurotransmitter signaling—the chemical messaging between nerve cells—and gene activity is concentrated in brain regions involved in movement, decision-making and habit formation, including parts of the cortex and striatum. Researchers Gary Heiman and Jay Tischfield said the work expands the field from a few strong genetic clues to more than 30 potential targets for treatment development.

So what changes in practice? Not a new medicine today. The result gives researchers a broader set of biological starting points for designing drugs aimed at underlying mechanisms rather than symptoms, while families and clinicians gain a clearer explanation of why OCD and chronic tic disorders can travel together. The study remains a genetic research finding, and any therapy based on these targets still lies ahead.