Catechol-O-Methyltransferase Genotype Influences Cognitive Performance and Concussion History in College Football Players

Catechol-O-Methyltransferase (COMT) is a gene that is active in the breakdown of dopamine and norepinephrine in the prefrontral cortex. It has two alleles, Val and Met, yielding three possible genotypes (Val/Val, Val/Met, Met/Met). The Val allele promotes higher enzyme activity resulting in greater levels of dopamine degredation and lower dopamine levels in the prefrontal cortex. Research suggests that those with Met/Met and Val/Met genotypes have better cognitive performance due to the lower enzyme activity associated with the Met allele. Additionally, previous findings show that Val/Val and Val/Met populations have higher concussion rates, which may be due to higher levels of dopamine degredation due to the Val allele. PURPOSE: To investigate association between COMT and executive cognitive function in student-athletes and how certain genotypes affect concussion history. METHODS: 18 college football players (age 18 0.77 years) were genotyped for COMT. Participants then performed cognitive tests using Immediate Post-Concussion Assessment Cognitive Testing (ImPACT). ImPACT obtains concussion history and measures cognitive function by using several neuropsychological tests involving word discrimination, attention span, response variability, working memory and recall, and reaction time. RESULTS: 7 subjects were Met/Met genotype and 11 were Val/Met. Met/Met subjects scored higher on verbal memory test (p = .329), visual memory test (p= .080), and visual motor test (p = .163). Results also show that only 14% of Met/Met subjects reported history of concussions while 27% of Met/Val subjects reported suffering at least one concussion. CONCLUSIONS: While data collection is ongoing, our preliminary data supports previous findings that the Val allele decreases cognitive performance and increases risk of concussions.