SPORTS stars owe a degree of their success to their parents – more specifically, the genes they inherited. “There’s no doubt that genetics plays some role in athletic performance,” says Stephen Roth, a geneticist at the University of Maryland. Heritability studies on identical and non-identical twins suggest that up to 80 per cent of differences in athletic prowess can be attributed to genes, not training.
Exactly which of our many genes make up a winning genome is tricky to pin down, but there are some candidates that appear to be tied to top performance.
In 1998, researchers discovered differences between two variants of the gene that codes for angiotensin-converting enzyme, which helps heart tissue to grow in response to training and muscles to use oxygen. One form of the gene confers useful traits on endurance athletes such as marathon runners. The other has been linked to success in sports that require shorter bursts of power, and is common among elite swimmers.
Another candidate gene is ACTN3. The fibres that form muscle come in two varieties, fast twitch and slow twitch, and ACTN3 controls how much of each fibre a person has. Slow twitch fibres are better at using oxygen over longer periods of time, making them handy for endurance events. Power athletes such as weightlifters, on the other hand, need the quick power bursts provided by fast twitch fibres.
Performance isn’t all about muscle, though. There’s also the mental toughness required to stick at…