By the time the last athletes received their medals at the London Olympics, a record number of competitors had undergone testing for performance enhancers. The International Olympic Committee took over 6,000 blood and urine samples to screen for performance-enhancing drugs that athletes could use to boost their abilities. Despite this massive effort to keep the competition fair, the committee is already predicting even greater efforts in future games as it contends with athletes who risk trying a new way to boost performance: gene doping.
Though no athlete has been found guilty of gene manipulation yet, the idea that certain power genes could enhance athletic prowess no doubt presents a strong temptation. Currently, gene therapy is undergoing testing in people with inherited disorders such as muscular dystrophy and sickle cell anemia. Ambitious and unscrupulous athletes could use the same technology to gain a competitive advantage.
The temptation is bolstered by mounting evidence that certain elite athletes naturally possess these genes. Naturally occurring variations of over 200 genes have been identified as important to athletic success. One gene variant carried by Finnish cross-country skier Eero Mäntyranta is the erythropoietin receptor gene EPOR, which causes him to produce extra red blood cells, boosting his oxygen-carrying capacity by 25 to 50 percent. This probably helped him earn his seven Olympic cross-country ski medals.
Another, the I variant of the ACE gene found in 94 percent of the Sherpa people in Nepal and in elite British long-distance runners, is associated with increased endurance. However, the gene by itself, working in isolation, likely does not guarantee any improved athletic performance. For example, about half of Eurasians and 85 percent of Africans carry at least one copy of this endurance gene variant.
Athleticism is not likely associated with just one particular form of a gene but results from a combination of traits that provide a natural advantage. Becoming an elite athlete requires extraordinary dedication, hard work and professional training.
As gene therapy to treat medical conditions gains momentum and results, the sporting world might be suspicious of patients treated with this therapy. If someone undergoes gene therapy using a variant like the EPOR gene to cure familial erythrocytosis type 1, the athlete could be ineligible to compete in the Olympics if the committee bans gene manipulation altogether.
Neither gene therapy nor gene doping are ready for prime time, but that is unlikely to stop an unscrupulous person from offering these services or an unethical athlete from trying them. Given the fame and money that come with athletic greatness, gene doping will inevitably become an issue in future Olympic Games and other athletic events. As sports governing bodies develop tests to identify gene doping, they will have to consider how to differentiate between naturally gifted athletes and those deliberately modifying their genes.