Catechol-O-methyltransferase gene and obsessive-compulsive symptoms in patients with recent-onset schizophrenia: Preliminary results

The catechol-O-methyltransferase (COMT) gene is a candidate gene for schizophrenia because of its role in the breakdown of dopamine in the prefrontal cortex. The COMT gene contains a functional polymorphism changing enzyme activity that has been associated with some neuropsychiatric (endo)phenotypes, e.g. cognitive performance and anxiety. In this study we investigated the association between the COMT Val¹⁵⁸Met polymorphism and obsessive-compulsive symptoms in patients with schizophrenia. Severity of obsessive-compulsive symptoms in 77 male patients with recent-onset schizophrenia was assessed using the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), and the COMT Val¹⁵⁸Met polymorphism was genotyped for these patients. We found a significant effect of the COMT genotype on Y-BOCS scores: the Val/Val genotype was associated with the highest Y-BOCS scores, whereas patients with the Met/Met genotype had the lowest Y-BOCS scores. Our data suggest that the COMT high-activity Val allele is associated with more obsessive-compulsive symptoms in young patients with schizophrenia. These results support the hypothesis that the COMT Val¹⁵⁸Met polymorphism may be a modifier gene for the symptomatology of schizophrenia.