New insights and perspectives on the genetics of obsessive-compulsive disorder.

Psychiatric genetic research has exploded in search of polygenic risk factors over the past decade, but because of the complexity and heterogeneity of mental illnesses, using the current understanding of the genome has not reached the conclusion of finding a cause for psychiatric disorders. Obsessive-compulsive disorder is a relatively common and often debilitating neuropsychiatric disorder that has not been the primary focus in psychiatric research. Clinicians and researchers who have dedicated to investigate the genetics of obsessive-compulsive disorder have detected a strong genetic involvement. This review will provide an update and a new perspective on the current understanding of the genetics of obsessive-compulsive disorder, which includes epidemiological data, family and twins studies, candidate gene studies, genome-wide association studies, copy-number variants, imaging genetics, epigenetics, and gene-environment interaction.