Endophenotypes of obsessive-compulsive disorder: Current status and future directions

► Twin studies show that OCD stems from a complex mix of general and specific factors. ► The study of endophenotypes may facilitate research into the etiology of OCD. ► Several promising biological and cognitive endophenotypes have been identified. ► Research is needed to identify endophenotypes associated with general etiologic factors. ► Research is needed to identify endophenotypes linked to symptom-specific etiologies.