As a cluster of unusual profiles came across the screens in a Tokyo drug-testing laboratory examining urine from Asian Games athletes last October, it was evident something was wrong. Indeed, these were the first signs athletes were using the potent anabolic steroid dihydrotestosterone (DHT).
Ten Chinese athletes were caught with the banned male hormone before and during the Asian Games, and two more Chinese female weightlifters were caught a month later at the World Championships.
All were found with excessive amounts of DHT, and the results have propelled the International Olympic Committee's medical commission to devise an acceptable test for the drug within the year.
It is but the latest example of how the athletes stay ahead of the pharmacologists in the war on drugs in sports. Now that DHT has been identified, athletes probably will move on to something else.
Donald Catlin, director of the IOC-accredited laboratory at UCLA, said pharmacologists have monitored DHT for several years, but had not approved a standard test for the hormone because they did not have proof athletes were using it.
"It takes a situation like this where there is a remarkable series of cases," he said.
Because it is a naturally produced substance in men and women, DHT from an external source, just like testosterone, is difficult to detect. DHT is more difficult to verify than testosterone because it is 10 times as potent and is an effective muscle-building agent in smaller doses.
But drug testers say they have an advantage because, unlike testosterone, DHT alters a number of related chemical ratios in the body.
The standard measure will be similar to testosterone, which is based on a ratio to another hormone, epitestosterone. If an athlete has a 6-1 ratio, testosterone to epitestosterone, he or she is declared positive because that exceeds the natural 1-1 ratio. With DHT, there will be about six ratios to help laboratories make a case.
DHT is available as a pharmaceutical only in France. It comes in a gel and is rubbed into the skin. It is preferred to testosterone, which is taken by injection.