No Evidence of a Common DNA Variant Profile Specific to World Class Endurance Athletes

There are strong genetic components to cardiorespiratory fitness and its response to exercise training. It would be useful to understand the differences in the genomic profile of highly trained endurance athletes of world class caliber and sedentary controls. An international consortium (GAMES) was established in order to compare elite endurance athletes and ethnicity-matched controls in a case-control study design. Genome-wide association studies were undertaken on two cohorts of elite endurance athletes and controls (GENATHLETE and Japanese endurance runners), from which a panel of 45 promising markers was identified. These markers were tested for replication in seven additional cohorts of endurance athletes and controls: from Australia, Ethiopia, Japan, Kenya, Poland, Russia and Spain. The study is based on a total of 1520 endurance athletes (835 who took part in endurance events in World Championships and/or Olympic Games) and 2760 controls. We hypothesized that world-class athletes are likely to be characterized by an even higher concentration of endurance performance alleles and we performed separate analyses on this subsample. The meta-analysis of all available studies revealed one statistically significant marker (rs558129 at GALNTL6 locus, p = 0.0002), even after correcting for multiple testing. As shown by the low heterogeneity index (I2 = 0), all eight cohorts showed the same direction of association with rs558129, even though p-values varied across the individual studies. In summary, this study did not identify a panel of genomic variants common to these elite endurance athlete groups. Since GAMES was underpowered to identify alleles with small effect sizes, some of the suggestive leads identified should be explored in expanded comparisons of world-class endurance athletes and sedentary controls and in tightly controlled exercise training studies. Such studies have the potential to illuminate the biology not only of world class endurance performance but also of compromised cardiac functions and cardiometabolic diseases.

Major genetic effects on airway-parenchymal dysanapsis of the lung: the Humboldt family study

We examined familial resemblance and performed segregation analysis for the maximal expiratory flow rate at 50% of vital capacity (Vmax50) and the ratio of Vmax50 to forced vital capacity (FVC), based on data from 309 nuclear families with 1,045 individuals in the town of Humboldt, Saskatchewan, in 1993. Vmax50 is considered as an index of airway function and Vmax50/FVC is considered as an index of airway-parenchymal dysanapsis. Both Vmax50 and Vmax50/FVC were preadjusted for host characteristics (age, height, and weight), environmental factors, and history of respiratory symptoms and diseases in four separate groups (mothers, fathers, daughters, and sons). Both Vmax50 and Vmax50/FVC showed low father-mother correlations and significant parent-offspring and sibling-sibling correlations. Segregation analysis indicated that for residual Vmax50, the model of no-parent-offspring transmission with possible heterogeneity between two generations fitted the data as well as did the general model with arbitrary transmission probabilities. The Mendelian hypothesis for Vmax50 was rejected, which was consistent with our previous findings for other indexes of airway function. For residual Vmax50/FVC, however, a single locus explained all the familial resemblance and both no-parent-offspring-transmission hypotheses [tau(AA) = tau(AB) = tau(BB) = qA and tau(AA) = tau(AB) = tau(BB)] were rejected. The study provides evidence for a single locus influencing airway-parenchymal dysanapsis.