4101Identification of genetic variants associated with the cardiovascular disease risk factor, low aerobic fitness - The HUNT study

Abstract

Abstract Abstract Background: Low maximal oxygen uptake (VO2max) is a strong and independent risk factor for all-cause and cardiovascular disease (CVD) mortality. Although physical activity is a major determinant of VO2maxlevel, genetics contribution is estimated to be ∼50%. Methods We performed a genetic association study on 123.545 single-nucleotide polymorphisms (SNPs) and directly measured VO2max in 3470 individuals (exploration cohort). The candidate SNPs were subsequently analyzed in a separate cohort of 718 individuals (validation cohort), in addition to 7 wild-card SNPs previously associated with VO2max, but not included on the chip used in the exploration cohort. Sub-analyses were performed for each gender. In silico analysis and genotype-phenotype databases were used to predict physiological function of the SNPs. Results In the exploration cohort, 42 SNPs were associated with VO2max (p<5.0×10–4). Six of the candidate SNPs were also found to be associated with VO2max in the validation cohort (p<0.05, either in men, women or both), in addition to three wild-card SNPs. By using these nine SNPs we created a genetic score for inborn VO2max-level. Together, these nine SNPs explained ∼8% of the variation in VO2max, and discriminate individuals with inborn high versus low VO2max based on simultaneous carriage of multiple favorable alleles. The cumulative number of favorable SNPs correlated negatively with the presence of several CVDrisk factors, e.g. waist-circumference, visceral fat, fat %, cholesterol levels and BMI. In silico analysis indicated that several of the SNPs influence gene expression across multiple organs, including adipose tissue, skeletal muscle and heart. Conclusion We identified six novel genetic variants associated with VO2max, and validated three SNPs previously associated with fitness related traits. Acknowledgement/Funding K.G. Jebsen Foundation, the Norwegian Health Association, the Liaison Committee between the Central Norway Regional Health Authority (RHA) and NTNU