Association ofGNB3C825T Polymorphism with Peak Oxygen Consumption

Abstract

The C825T single nucleotide polymorphism (SNP) in the guanine nucleotide-binding protein, beta polypeptide 3 ( GNB3) gene gives rise to a splice variant, GNB3s that has enhanced G protein activation and signal transduction activity. This variant has been reported to be associated with cardiovascular disease, diabetes and obesity. We studied this SNP in 95 healthy 18 to 30 year-old African American university students to determine its association with aerobic capacity and cardiorespiratory fitness as measured by peak oxygen consumption (VO (2)peak). We also tested the effect of heart rate variability (HRV) as an independent predictor of VO (2)peak. We tested the association of the SNP and HRV with VO (2)peak in a multivariate regression analysis with appropriate adjustments of covariates, under dominant and recessive models. We found a significant independent association of the 825T allele with VO (2)peak under the dominant model (beta-coef.=-0.101, P=0.0442). We also observed that HRV marginally influenced VO (2)peak. This finding suggests that GNB3 C825T polymorphism is associated with VO (2)peak which is influenced by autonomic modulation of heart rate in African Americans.

Is there an interaction between BDKRB2−9/+9 and GNB3 C825T polymorphisms and elite athletic performance?

“…Rankinen et al (2002b) found that the GNB3 C825T polymorphism plays a minor role in heart rate and body fatness regulation in African Americans, as well as in the responsiveness of resting blood pressure to endurance training in African American women. This polymorphism was also associated with VO 2max in non‐athletes (Faruque et al, 2009), and our group recently reported a higher frequency of the TT genotype in Israeli elite endurance athletes than in sprinters of the same origin (Eynon et al, 2009).…”

GNB3 C825T Polymorphism and Myocardial Recovery in Peripartum Cardiomyopathy

“…Black subjects with the GNB3 TT genotype had a greater heart rate response to the cold pressor test of sympathetic activation (28), suggesting the GNB3 polymorphism may influence vascular tone through alterations of autonomic function. Metabolic stress testing revealed an association between the GNB3 T allele and poorer peak oxygen consumption and altered heart rate variability, further suggesting that the T allele may be associated with autonomic modulation and cardiovascular stress response (29). …”

GNB3C825T Polymorphism and Elite Athletic Status: A Replication Study with Two Ethnic Groups

“…It is associated with VO 2max in nonathletes [5] , and Eynon et al recently reported a higher frequency of the TT genotype in Israeli elite endurance athletes than in sprinters of the same origin [4] . Whether the latter results can be extrapolated to other populations remains to be elucidated.…”