OUR Olympic superstars Usain Bolt and Elaine Thompson have not only made sporting and international news recently, they have also made it into the medical news arena.

Medscape, the leading online global information source for health care professionals worldwide, which offers the latest medical news and expert perspectives, published an article at the end of August entitled ‘ Can a Genetic Test tell if your kid is the next Usain Bolt?‘

The article asked the question: ‘Are there genes that predict superior performances in particular sports?’; and went on to describe how Bolt and Thompson captured the men’s and women’s 100 and 200 metres for their country as the world watched Jamaican sprinters outpace their competition at the 2016 Olympic Games.

The article reported that the performances of these athletes have led many spectators to speculate on the role of genes in sporting ability.

GENETIC TESTS

In questioning whether genetic tests could be done for athletic ability, the article wondered whether marathon runners from Kenya breathe oxygen faster and whether genetic traits allow the Chinese to dominate ping-pong.

The answer to such questions could make a huge difference to the multibillion-dollar business of sports, fitness and nutrition, with some firms already offering to test the genes of those who aspire to become athletes. Based on the results, they claim they would offer an individually tailored training regimen or vitamin prescription. This, they say, could steer a 10-year-old child with the potential to become the next great swimmer away from a fruitless effort to technically master a craft and into the nearest swimming pool.

SOME ARE SCEPTICAL

However, some geneticists are balking at such propositions. A consensus statement made by 24 prominent geneticists and exercise physiologists from around the world has declared that genetic tests have no role to play in the identification of talent or the individualised prescription of training to maximise performance.

They oppose the claims made by companies such as AnabolicGenes, which promise to analyse your DNA in order to have a clear view on how your body responds to diet and training, or Genomic Express, which suggests that it can tell whether you have a genetic advantage in either athletic power or endurance events.

Admitting that genes matter in athletic achievement, however, the geneticists agree that being tall helps basketball players, for example, since genes help to determine a person’s height. More subtle genetic traits can also make a big difference.

At the 1964 Winter Olympics, Eero Antero Mantyranta, a skier from Finland, easily swished past his competition to win two gold medals and a silver medal in the cross-country skiing events. When tested, Mantyranta’s blood showed high levels of erythropoietin (EPO), a hormone produced by the kidney that stimulates the formation of red blood cells by the bone marrow. With increased levels of EPO, there would be increased numbers of red blood cells, and since the red blood cells carry oxygen within a person’s bloodstream, the increased amount of oxygen present results in an increased capacity for exercise and improved performance.

Genetic research revealed a single mutation had occurred to Mantyranta’s erythropoietin receptor gene, giving him 50 per cent more red blood cells than the average person. Whilst this process had naturally occurred in this athlete, decades later, cyclist Lance Armstrong admitted to obtaining injections of the synthetic version of this hormone, and so was heavily penalised and disqualified from future cycling events for his lying and cheating.

RESEARCH INTO THE ROLE OF GENES

A handful of examples similar to that of Mantyranta have occurred in the history of sports, and so some geneticists believe such instances are worthy of research. Consequently, there is now a study called ELITE, which looks at the genes of the fittest people on Earth, with the intention to discover the genes that make these people somewhat superhuman. Once discovered, the genes could be studied to help scientists, for example, develop drugs that could benefit others.

One example is an aerobics instructor in Dallas, Texas, whose low-density lipoprotein level (LDL) was astonishingly low at 14mg/dl, where 129mg/dl was the average blood level reading of people in the United States. Research into the genes of this woman as well as that of another woman with a similar profile helped develop what is called PCSK9 inhibitors — a new class of cholesterol-lowering drugs.

Would such discoveries and testing help unlock a child’s athletic potential?

Certainly, there will come a day when we will know so much more than we do today, and some kind of an advisory could then be put together. Until then, however, we ought to proceed cautiously along this route of research and make no premature announcements.

Studying genes is a complicated process, since important athletic traits usually result from a complex interaction of multiple genes as well as environmental factors. Consequently, studying genes is only the beginning, as culture, personality, climate and altitude, as well as social support all may play important roles in an athlete’s development.

Derrick Aarons MD, PhD is a consultant bioethicist/family physician, a specialist in ethical issues in medicine, the life sciences and research, and is the Ethicist at the Caribbean Public Health Agency (CARPHA). (The views expressed here are not written on behalf of CARPHA)