Concussion-associated gene variant COMT rs4680 is associated with elite rugby athlete status

Abstract

Objective: Concussions are common match injuries in elite rugby and reports exist of reduced cognitive function and long-term health consequences that can interrupt or end a playing career and produce continued ill health. The aim of this study was to investigate the association between elite rugby status and eight concussion-associated risk polymorphisms. We hypothesized that concussion-associated risk genotypes and alleles would be underrepresented in elite rugby athletes compared to non-athletes. Design: A case-control genetic association study. Setting: Institutional (university). Participants: Elite Caucasian male rugby athletes (n = 668, mean (standard deviation) height 1.85 (0.07) m, mass 102 (12) kg, age 29 (7) yr) and 1015 non-athlete Caucasian men and women (48% men). Interventions: Genotype was the independent variable, obtained via PCR of genomic DNA using TaqMan probes. Main Outcome Measure: Elite athlete status, with groups compared using χ2 and odds ratio. Results: The COMT rs4680 Met/Met (AA) genotype, Met allele possession and Met allele frequency were lower in rugby athletes (24.8%, 74.6% and 49.7%, respectively) than non-athletes (30.2%, 77.6%, and 54.0%; P < 0.05). The Val/Val (GG) genotype was more common in elite rugby athletes than non-athletes (odds ratio 1.39, 95% confidence interval 1.04-1.86). No other polymorphism was associated with elite athlete status. Conclusions: Elite rugby athlete status is associated with COMT rs4680 genotype that, acting pleiotropically, could affect stress resilience and behavioral traits during competition, concussion risk and/or recovery from concussion. Consequently, assessing COMT rs4680 genotype might aid future individualized management of concussion risk amongst athletes.