Association between GRIN2A promoter polymorphism and recovery from concussion

Abstract

Objective: To determine genetic variability within the N-methyl-D-aspartate receptor 2A sub-unit (GRIN2A) gene promoter and its association with concussion recovery time. The hypothesis tested was that there would be a difference in allele and/or genotype distribution between two groups of athletes with normal and prolonged recovery.

Methods: DNA was extracted from saliva collected from a total of 87 athletes with a physician-diagnosed concussion. The (GT) variable number tandem repeats (VNTR) within the promoter region of GRIN2A was genotyped. The long (L) allele was an allele with ≥25 repeats and the short (S) allele was an allele with <25 repeats in the GT tract. Participants’ recovery time was followed prospectively and was categorized as normal (≤60 days) or prolonged (>60 days).

Results: LL carriers were 6-times more likely to recover longer than 60 days following the concussive event (p = 0.0433) when compared to SS carriers. Additionally, L allele carriers were found more frequently in the prolonged recovery group (p = 0.048).

Conclusion: Determining genetic influence on concussion recovery will aid in future development of genetic counselling. The clinical relevance of genotyping athletes could improve management of athletes who experience concussion injuries.

• Brain injury
• NR2A sub-unit
• calcium

Acknowledgements

We would like to thank Michael D. Brown, Dr. Jamie Mansell, Dr. Dani Moffit and Dr. Tracey Covassin for their review of this research. We are grateful to the Jayne Haines Center for Pharmacogenomics and Drug Safety, Temple University School of Pharmacy for the help in establishing the protocols and conducting the genotyping experiments.

Declaration of interest

The authors report no conflicts of interest. Funding was received in part by the Eastern Athletic Training Association (EATA) grant (award number p0219092).