Quoting from WebMD: "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."

SOURCES: Lasne, F. Molecular Therapy, August 2004; vol 10. News release, American Society of Gene Therapy.