The New York Times highlights the “testosterone loophole” in anti-doping tests reporting on a recent study that finally explains the phenomena that allows some athletes to get away with indiscriminate use of exogenous testosterone. This is the same study that has been discussed in the blogosphere for over a month on various doping and steroid-related websites including MESO-Rx, Steroid Report, Trust But Verify and Rant Your Head Off. But the New York Times story will provide mainstream exposure to the weakness in current doping protocols implemented by WADA using the testosterone:epitestosterone (T:E) ratio test (”Some Athletes’ Genes Help Outwit Doping Test,” April 30).
Researchers have long known that some men, Asians in particular, seemed to be able to take the drugs without getting caught, although no one had identified the cause of the phenomenon. Without gene testing, there is no way to know whether any athletes have exploited this doping loophole, but Dr. Catlin says he suspects some athletes discovered their invulnerability by accident and took advantage of it.
Men with the gene deletion still metabolize testosterone, Dr. Schulze says. But, she adds, she does not know where the hormone goes. “We have no idea,” she said. “That’s what we’re trying to find out.”
The gene in question adds a chemical, glucuronide, to testosterone. That converts it from a substance that dissolves in oil into one that dissolves in water and urine.
Athletes with a specific gene deletion (UGT2B17 homozygous deletion/deletion genotype) are genetically predisposed to pass the testosterone doping test.
The results were unambiguous: the test worked for most of the men, showing that they had taken the drug. But 17 of the men tested negative. Their urine seemed fine, with no excess testosterone even though the men clearly had taken the drug.
It was, researchers say, a striking demonstration of a genetic discovery. Those 17 men can build muscles with testosterone, they respond normally to the hormone, but they are missing both copies of a gene used to convert the testosterone into a form that dissolves in urine. The result is that they may be able to take testosterone with impunity.
The New York Times also reports that the “prevalence in other groups is not known.” But this is inaccurate. As reported in MESO-Rx last month, there is a lot of data on other groups involving the UGT2B17 gene.
(Thanks to Rehan Jalali of TSRF for alerting me to the Times article.)
Is it conceivable that every Major League Baseball player could use performance-enhancing dosages of testosterone and never test positive for a banned substance? Sure, although unlikely, the information is out there. There are more than a few chemists who could figure out how to exploit a testosterone loophole in drug testing:
I could figure out how to take a fair amount of testosterone and you’d never catch me, and if I can say that, a lot of others can too.
Who said that? Patrick Arnold? Bruce Kneller? Maybe another creator of designer supplements? Actually, it was Don Catlin, the former director of UCLA’s Olympic Analytical Testing Lab and founder of the Anti-Doping Research Institute.
This statement reflects Catlin’s firsthand knowledge of loopholes for testosterone detection in existing drug testing protocols. If the sport relies exclusively on the testosterone:epitestosterone ratio (T:E ratio) test with an allowable ratio of 4:1 or 6:1, then this allows athletes to use performance-enhancing amounts of testosterone without exceeding that ratio.
Recently introduced carbon isotope ratio (CIR) test seeks to determine whether the testosterone metabolites are synthetic(plant-based) or natural (endogenous). This may not be foolproof; but has been used to corroborate elevate T:E ratios (e.g. Floyd Landis case).
However, depending on the sport, the CIR test may never be used unless an athlete fails the T:E ratio test. Furthermore, some sports don’t even use the CIR test (e.g. Major League Baseball)
In these cases, an athlete can exploit the testosterone loophole in testing.
The “cream” used by BALCO was not a novel undetectable designer steroid or sophisticated method of administering steroids. It was simply a variation of the testosterone and epitestosterone cocktail that had first been used over 20 years ago to fool drug testers.
BALCO athletes simply used a transdermal delivery system to administer the testosterone and epitestosterone mixture. Transdermal testosterone has a slower release and results in lower peak blood concentrations. This makes is easier for athletes to use the prohibited anabolic steroid testosterone and remain within the 4:1 to 6:1 acceptable T:E ratio as well as avoiding excessive absolute levels of metabolites.
Even after the entire BALCO scandal, the “testosterone loophole” has not been closed. The “cream” is just as effective as ever for a professional baseball player. And no solutions to this loophole contained within the Mitchell Report.
