How Doctors Help The Dopers

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Gene-based compounds will be much harder to track than a synthetic steroid like andro or a stimulant like ephedrine. That's because compounds delivered directly to muscle generally remain corralled there, rarely reaching the bloodstream or urine, where they could be traced. Though genetic treatments are not yet out of the lab, WADA has enlisted the help of researchers who have provided them with ideas for identifying competitors taking advantage of the new therapies. (Here's a hint: start with the record breakers.) "I don't think anyone will be competing in Athens with genetic enhancement," says Dr. H. Lee Sweeney, chairman of the department of physiology at the University of Pennsylvania School of Medicine and a consultant to WADA. "But I wouldn't be willing to make the same bet about Beijing."

By the Beijing Games in 2008, Sweeney predicts, athletes may be availing themselves of a genetic treatment designed for muscular dystrophy, years ahead of safety and efficacy trials, and years ahead of when patients may have access to the remedy. "I'm sure there are going to be scientists willing to set up illegal clinics to treat athletes who want genetic enhancement if they pay enough money," he says.

Because of their particular focus, muscular-dystrophy labs stand to provide a rich pipeline of potential doping agents. Muscular dystrophy is a genetic condition in which muscle can no longer repair the tiny abrasions that come from normal wear and tear, and begins to waste away. The disease mimics an exaggerated form of the stress that highly trained athletes inflict on their muscles. To restore the balance in favor of regeneration, researchers are isolating the myriad growth factors and other biochemical compounds that regulate the musclemaking factory.

So far, two major strategies hold the most promise: boosting levels of a hormone called insulin-like growth factor 1 (IGF-1), which encourages muscle repair; and removing myostatin, the body's natural check on uncontrolled muscle growth. Versions of IGF-1 are already available at pharmacies and nutritional-supplement stores, where they are marketed as muscle boosters, but scientists know that taking this oral form of the hormone does very little for building muscle and can have harmful effects on the heart. That hasn't stopped some athletes from trying it. "I'm convinced that some athletes are using a combination of IGF-1 and human growth hormone," says Nadia Rosenthal, an IGF-1 researcher at the European Molecular Biology Laboratory in Rome. The theory behind the combo is that human growth hormone signals the liver to secrete more IGF-1, keeping blood levels high. "These athletes know a little bit about how [the hormones] work, and for them, a millisecond could be the difference between gold or nothing," she says. What they don't seem to realize is that circulating IGF-1 is less effective, and more dangerous, than the version that is concentrated in the muscle.