Gene Doping

Doping, which is the use of banned substances to enhance an athlete’s performance, has been a significant concern in the sports community for a while now. But with advances in technology, it became possible to detect PEDs (Performance Enhancing Drugs) through testing the samples of blood and urine of athletes.

The progress of research on genes has made gene therapy possible. It is the modification of genes to produce therapeutic effects, especially in cases of genetic diseases. Gene therapies, if used ethically, are potentially life-saving in many instances. However, the fear of gene therapies being exploited for the sake of selfish purposes has also significantly increased.

Gene doping is one such case where specific genes can be modified to help an athlete enhance his performance in sporting events. The World Anti-Doping Agency defines it as the ‘non-therapeutic use of gene therapy’.

Gene doping can be considered as a branch of gene therapy. Hence, it works just like gene therapy. The genetic material containing the desired trait is delivered to the target cells through various vectors (usually viral). These viral vectors release a transgene in the target cells. Once the transgene is successfully incorporated into the cell, it replicates itself and expresses the desired trait.

Some potential candidates for gene doping are EPO, GH, IGF1, VEGFA, etc. EPO (erythropoietin) is a gene that encodes a glycoprotein hormone which increases the number of RBCs and thus the amount of oxygen supplied to the muscles. When introduced in an athlete’s body as an extra copy through gene doping, the EPO gene is believed to lead to overexpression of EPO, thus increasing blood supply to various organs. This, in turn, leads to increased oxygen binding capacity and higher endurance.

But this obviously comes with a price to pay. Doping with EPO could lead to serious side effects like hematocrits, which increases the likelihood of myocardial infarction and strokes.

In the early 2000s, Repoxygen, a drug containing a viral vector transferring EPO transgene, was developed to treat anaemia. This was soon found to be administered to young female athletes in Germany to maintain constant expression of EPO. However, Repoxygen is currently prohibited by the World Anti-Doping Agency.

The current tests to detect doping include testing samples of blood and urine of athletes. While this method effectively detects foreign substances in the blood, it isn’t an effective method to detect gene doping. The main issue with the detection of gene doping is that once the transgene is introduced in an athlete’s body, it is almost identical to its endogenous counterparts.

The current methods involve spotting the viral vectors in the athlete’s body. However, this method requires information about the exact location of the injection. Collection, storage and analysis of the samples in a short period also makes this method quite ineffective. Monitoring the immune response of the athletes is also considered a viable method. But it can’t be solely trusted as the athlete could also have an immunological response to different viral infections.

Above all comes the question of fairness and ethics. Jamaica’s Usain Bolt currently holds the world record for the 100m sprint, which he was able to run in 9.58 seconds. How would you feel about a ‘super athlete’ with doped genes breaking his record by a considerable margin? Would you consider it a fair record abiding by the basic ethics of sports? Thanks to the World Anti-Doping Agency and other sports organizations, there is a hope to sustain the idea of fair play in sport while also protecting the athletes from adverse health effects of gene doping.