Last Thursday, we hosted a ScienceLive chat on "Science at the Olympics " in which we asked researchers for their views on the new scientific innovations set to enter the Olympic stage this week in London. We intended to discuss prosthetics and performance-enhancing drugs, but unfortunately our blood-doping expert, Don Catlin, was unable to join us. Catlin is an expert on drug use in sports and a professor emeritus at the University of California, Los Angeles (UCLA). He founded the UCLA Olympic Analytical Laboratory, which is a national testing site for performance-enhancing drugs and is used by the NCAA, the National Football League, Major League Baseball, and the U.S. Olympic Committee.
After the chat we sent him your questions about athletes' use of agents such as erythropoietin (EPO), which produces extra red blood cells, and human growth hormone (HGH), which increases strength. He also discussed epitestosterone, a hormone that is almost identical to testosterone but does not improve athletic ability. It is used to mask high levels of testosterone. Readers also asked about the implications of biological passports that record individual athletes' doping test results and the high-profile Bay Area Laboratory Cooperative (BALCO) scandal, which outed several prominent professional athletes for using performance-enhancing drugs. Below are his responses.
Q: What new doping methods are you most concerned about?
D.C.: My main concern involves attempts to thwart the current tests by using mini-doses of EPO and EPO-like drugs and HGH. There are people who search for ways to use doping agents and not get caught. They are performing clandestine clinical research but they do not have ethics committee approval, and of course they do not file reports on their studies. Nevertheless the "subjects" provide details to each other that describe their doses, the dates of the tests, and the test outcomes. In one sense their model is powerful because it relies on human testing doses and results. However, it lacks controls and lots of features of legitimate pharmacology protocols. We do not know how many people are involved, but there is some evidence that mini-doses of EPO may be avoiding positive test results. Eventually a low dose will not provide efficacy for the participants.
Q: Do you feel the biological passport system will hold up as a way of catching doping athletes?
D.C.: The theory behind the passport program is very sound, and all physicians can relate to it because they use it every day in their work. In practice the passports are very difficult to prove drug use. They cannot rely on legitimate clinical studies. They do rely on huge databases, but outliers can be complicated. The response range of the human body on the relevant variables is huge. By this time I would have expected more cases to have been publicized. The people making the decisions must be very careful—which is no doubt why there are not so many cases. The data are not available for review. I have data from my own studies but not from studies being conducted by the University of California, Irvine. I expect that in time, passports will result in more defensible cases of doping. It is one more tool in the armamentarium of the antidopers.
Q: Did the BALCO files provide any new information regarding the use of steroids and HGH?
D.C.: It did not provide any new information to me. I had been expecting this type of doping for several years; however, when I spoke at conferences about the possibility it was difficult to generate interest in a theoretical possibility. The BALCO affair was exceedingly important because it proved, without doubt, that designer drugs, epitestosterone to normalize the testosterone-epitestosterone ratio, etc., was in fact going on. What bothered me then and now is that Victor Conte, the president of BALCO, was able to use a legitimate commercial laboratory to work out the pharmacokinetics of testosterone and epitestosterone. The lab should have alerted the authorities that one of their clients was involved in aiding doping efforts.
I doubt that Patrick Arnold [the chemist who created the designer steroid tetrahydrogestrinone] knew that derivatized THG would break down in the injection port of the gas chromatography-mass spectrometer (GC-MS) instrument. That was probably beyond his chemical knowledge but it did prolong our studies of THG. Eventually, it required a major change in the way we screen for anabolic steroids. Now we use liquid chromatography-mass spectrometers because it does not require derivatization.
Q: Do you agree that certain compounds/drugs/chemicals/vitamins should be deemed illegal for competition? Why?
D.C.: Yes. I do believe that we should continue to use urine testing to enforce doping. I have thought about other ways to do that, but none will work. If we give up testing and allow all drugs, we will virtually compel athletes to dope because the drugs do enhance performance. If there is no testing all athletes will be equal again but all will be on drugs. Some will push the envelope and take high doses so there will be lots of adverse effects. We have to recognize that there are difficulties with urine testing. It is not the "perfect" solution, but on balance it is useful and better than the no-testing alternative. I believe that the authorities should do as much as they can to enforce doping control. There are probably alternative programs such as a volunteer doping control program. I also believe that the WADA [World Anti-Doping Agency] list could be reduced a bit.