COMT Val158Met polymorphism and executive functions in obsessive-compulsive disorder.

This study investigated the association between the catechol-O-methyl transferase (COMT) Val158Met polymorphism and executive functions in 101 patients with obsessive-compulsive disorder (OCD) and 100 healthy-control subjects (HS). Results showed that there was no significant difference for the genotype distributions between the OCD and HS groups. OCD-Met carrier subgroup's TMT B-A difference and lexical fluency scores were found to be significantly poorer than both HS subgroups. These findings suggest that lower activity of COMT associated with the Met allele, leading to higher levels of dopamine in the prefrontal cortex, lead to poorer executive function in OCD.