Impact of BDNF Val66Met polymorphism on olfactory functions of female concussed athletes.

Background: Concussions exert persistent effects on asymptomatic athletes, especially women. Among chief mechanisms of concussion recovery are alterations of neuronal plasticity. Olfactory function, often impaired following a concussion, greatly involves plasticity and, therefore, appears as a good candidate to study the deleterious effects of concussions. The BDNF Val66Met polymorphism (BDNF_Met), which reduces availability of BDNF in the brain, has surprisingly been associated with better recovery following concussion. Objective: This study examines the mediating effect of BDNF_Met on olfactory functions in asymptomatic concussed female athletes. Methods: Participants, 105 female university athletes, were divided into four groups based on their history of concussion (Concussion/No concussion) and BDNF polymorphism (BDNF Val66Val/Val66Met). Odour threshold, discrimination and identification were measured using the Sniffin' Sticks Inventory Test. Results: Concussed female BDNF_Met athletes performed significantly better than BDNF_Val counterparts on threshold ( F(1, 34) = 4.73, p < 0.05), discrimination ( F(1, 52) = 5.36, p < 0.05), identification tests ( F(1, 52) = 5.65, p < 0.05) and total olfactory scores ( F(1, 34) = 9.54, p < 0.05). Conclusion: These results support a genotypic effect of the BDNF Val66Met polymorphism on long-term olfactory function following a concussion in young female athletes. [ABSTRACT FROM AUTHOR]