Gene Doping May Not Elude Testing

Aug. 12, 2004 -- Doping using gene therapy rather than performance-enhancing drugs may not be as stealth as many have predicted. New research shows that gene doping may be detectable with currently available testing methods.

Many antidoping officials predict that doping using gene therapy will soon become the next challenge in keeping amateur and professional athletes clean.

Rather than using drugs to boost athletic performance by stimulating the production of red blood cells, proteins, or other endurance- and muscle-enhancing substances, gene therapy uses genes that are injected and transferred directly into a person's own cells. This will enable the production of substances that are identical to substances already produced naturally by our bodies.

Although most anabolic steroids and other banned performance-enhancing drugs are detectable in urine tests, it's been speculated that gene doping would be much harder to detect. In other words, would it be possible to tell if an athlete was born genetically gifted or had received the performance-enhancing genes as a result of gene therapy?

Gene Doping Detectable

In a letter published in the August issue of Molecular Therapy, French researchers say they found good reason to believe gene doping may be detectable.

In their study, monkeys were genetically doped with erythropoieten (EPO), a hormone that stimulates red blood cell formation and is often used to increase endurance in sports. Treatment with the hormone currently requires repeated injections and is detectable by antidoping urine tests.

But in this case, the EPO gene was injected directly into the monkey's muscle tissue. Researchers say muscle is a likely target for gene dopers, because it's easily accessible and plentiful.

Contrary to what had been predicted, the results of the experiment showed that the EPO protein produced by the genetically doped monkeys was different than the EPO protein produced naturally by nonenhanced animals and the injected gene produced was detectable by DNA screening. They say further tests are needed to determine if EPO gene doping would be detectable in urine tests.

"Although other methods of gene transfer exist and may be exploited for gene doping, and such methods are yet to be investigated, our results provide encouraging evidence that doping by gene transfer will likely not go undetected at least when skeletal muscle is the target," write researcher Françoise Lasne of thetNational Anti-Doping Laboratory in Chatenay-Malabry, France, and colleagues.