Cardiovascular health exists as a spectrum of wellness and disease states. Moreover, a significant portion of what defines these states is due to genetics. We hypothesize that there exist genes and pathways that dually contribute to both disease and extreme health states. Interrogating the ‘adaptive’ tail of the distribution for individuals with extreme phenotypes, such as high maximum oxygen uptake (VO2max) in endurance athletes, will inform prevention, cause and treatment of pathogenic (‘maladaptive’) conditions. 1 To date, most genetic studies in the athlete population have examined a subset of genes (out of more than 21,000 in the genome), using small sample sizes and qualitative measures of performance. To the best of our knowledge, there has not been a comprehensive genetic study of endurance athletes with strict quantitative eligibility criteria.2-4
The ELITE project (Exercise at the Limit – Inherited Traits of Endurance) intends to investigate the world’s best endurance athletes, i.e. individuals with extremely high VO2max. A primary goal is to determine what role genetic variation plays in athletic ability. One of the ancillary goals of the project is to understand the unique genetic differences contributing to extreme fitness in women versus men. We will sequence and analyze the genomes of elite level competitive athletes from various countries (including USA, Scandinavia, UK, Japan, and Brazil) who are highly successful in one of several endurance sports (such as running, cross country skiing, triathlon, cycling, rowing). We have recruited 750 elite athletes (142 women and 608 men) who have been consented and undergone enhanced whole exome sequencing and/or MEGA chip GWAS analysis. Inclusion criteria for the study restricts to the highest tail end (>99.98th percentile or 1/5000), i.e. VO2max >63 ml/kg for women and >75 ml/kg for men. Even with differential eligibility, skewed recruitment (1:4) is a challenge.
Our preliminary results show tantalizing evidence for potentially beneficial genetic variants in several highly plausible genes. Additionally, pilot burden testing on a subset of the athletes also showed promising results. While already promising, rigorous analysis, increased sample size and orthogonal replication is required as our next step.
- Mattsson CM, Wheeler M, Waggott D, Caleshu C, Ashley EA. Sports genetics moving forward - lessons learned from medical research. Physiol Genomics. 2016; 48(3):175-182.
- Bouchard C, Sarzynski MA, Rice TK, Kraus WE, Church TS, Sung YJ, Rao DC, Rankinen T. Genomic predictors of the maximal O₂ uptake response to standardized exercise training programs. J Appl Physiol (1985). 2011; 110(5):1160-70.
- Eynon N, Morán M, Birk R, Lucia A. The champions' mitochondria: is it genetically determined? A review on mitochondrial DNA and elite athletic performance. Physiol Genomics. 2011;43(13):789-98.
- Pitsiladis YP, Tanaka M, Eynon N, Bouchard C, North KN, Williams AG, Collins M, Moran CN, Britton SL, Fuku N, Ashley EA, Klissouras V, Lucia A, Ahmetov II, de Geus E, Alsayrafi M; Athlome Project Consortium. Athlome Project Consortium: a concerted effort to discover genomic and other "omic" markers of athletic performance. Physiol Genomics. 2016;48(3):183-90.