A Functional Polymorphism in the COMT Gene and Performance on a Test of Prefrontal Cognition

OBJECTIVE: In the prefrontal cortex, the enzyme catechol O-methyltransferase (COMT) is critical in the metabolic degradation of dopamine, a neurotransmitter hypothesized to influence human cognitive function. The COMT gene contains a functional polymorphism, Val158Met, that exerts a fourfold effect on enzyme activity. The current study investigated whether prefrontal cognition varies with COMT genotype. METHOD: Val158Met was genotyped in 73 healthy volunteers. A task of prefrontal cognition, the Wisconsin Card Sorting Test, was also administered. RESULTS: Subjects with only the low-activity met allele made significantly fewer perseverative errors on the Wisconsin Card Sorting Test than did subjects with the val allele. CONCLUSIONS: These data are consistent with those of previous studies, suggesting that a functional genetic polymorphism may influence prefrontal cognition.