Is the 5-HT(1Dbeta) receptor gene implicated in the pathogenesis of obsessive-compulsive disorder?

Obsessive-compulsive disorder (OCD) is a psychiatric condition for which strong evidence of a genetic component and serotonergic system involvement exists. Recent studies have shown that sumatriptan, a selective ligand of the serotonin (5-HT)(1Dbeta) autoreceptor, modifies OCD symptoms. The aim of this study was to investigate the presence of linkage disequilibrium between the 5-HT(1Dbeta) receptor gene, which has a variant caused by a silent G to C substitution at nucleotide 861 of the coding region, and OCD. DNA was collected from 67 probands who met DSM-IV criteria for OCD and from their living parents or siblings. Transmission Disequilibrium Test/sib-Transmission Disequilibrium Test analyses were then conducted with the DNA data. Thirty-two families were informative for the analysis, which showed a preferential transmission of the G allele to the affected subjects. If the results are confirmed, there may be important implications for the 5-HT(1Dbeta) receptor gene in the pathogenesis and treatment of OCD.