Former double world champion Tyson Gay has signed up to work with sprint guru John Smith in Los Angeles.

Washington - Eight of the most gifted sprinters in the world are settling into their blocks on the start line of the 100m final at a major championship. The tension is almost unbearable; the rewards for success are huge.

To the spectators in the stadium and the millions watching on TV, it is a spectacle without equal in sport. But what very few of them will suspect is that it is statistically likely that at least one of those runners will have a genetic make-up allowing him to take performance-enhancing steroids for his entire career – and never fail a drug test.

Science fiction? Far from it.

Now imagine the starting blocks of a swimming final at an international event in Asia – the 2014 Asian Games in Incheon, South Korea, for example. It is quite feasible that half of the athletes about to dive into the water – perhaps as many as six out of eight depending on whether they are Chinese, Japanese, Korean or from another background – also have bodies that naturally allow them to take drugs, but not get caught.

Astonishing though it sounds, significant numbers of sportspeople are born to dope, and get away with it. The proportion ranges from about one in 10 of those with European ancestry to one in five with African heritage, and up to a staggering two-thirds of people in some Asian countries, notably Korea.

These shocking statistics go part of the way to explaining the vast difference between the numbers of elite athletes who are taking banned performance-enhancing drugs and the numbers being caught.

The most common type of drug test analyses urine to compare levels of testosterone (T) and another hormone, epitestosterone (E) to give a T/E ratio. This test can signify the use of all kinds of illegal drugs, including anabolic agents, which are the most commonly found drugs in dopers, 50 percent of positive drug tests being for steroids – or artificial testosterone.

When the T/E ratio exceeds four to one, it signifies possible doping. But people who have the “doping with impunity” gene variant – carriers have two copies of a version of a gene called UGT2B17 – do not return positive tests, even if they have been doping. The gene variant keeps the T/E level low, naturally. That means huge swathes of the population have a licence to dope.

Christiane Ayotte, a veteran in the fight against doping, says this is shocking and frustrating because tests exist which could catch more drug cheats – including those whose genetic make-up enables them to dope with impunity – but these tests are not used by all anti-doping organisations or national sports federations.

Ayotte said last week: “I am sure many people will be shocked by the fact that sportsmen and women can be doping under the radar.

“It would not be scientific to guess how many of all the tests in the world are still simple urine screening tests, which allow those with this gene to pass tests, but it remains the most common testing procedure.

“That is frustrating because it would not be so difficult to introduce other layers of testing, not just the T/E ratio, to catch people. But too many (anti-doping) organisations and federations don’t do it.”


Official figures on global testing in sport last year, collated by the World Anti-Doping Agency (Wada), show anabolic agents – steroids – remain the most commonly found illegal drug in the cheats’ armoury. More than half of all positive tests in the world last year were positive for anabolic agents, which placed them way ahead of the next most common category of banned drug, stimulants, which were responsible for 15.5percent of failed tests.

Steroids may seem “old- school” but even some of the cases of recent times have involved them, including the positive test just a few weeks ago of the US’s former world 100m champion, Tyson Gay.

He was caught because the testing used on his sample was a more advanced test – a carbon isotype test. These are typically used when a T/E ratio test has already flagged up a problem.

A Swedish study found the “doping with impunity” gene variant occurs in 66.7 percent of Asian populations and almost 10 percent of Caucasians. That study recommended that ascertaining every individual’s gene make-up would help to close the loophole open to those born to dope. But such profiling would be expensive, and possibly controversial among those who would regard it as a further invasion of privacy.

As the body that encourage national doping agencies and governing bodies to do more testing and more complex testing, Wada faces an uphill task. Wholesale changes in the Wada code, to be updated by 2015, will address this, as part of a range of new “smart” testing.

Another study into the “doping with impunity gene”, which looked at football players and was published in the British Journal of Sports Medicine, found that up to 81 percent of some Asian populations had the “impunity” gene variant, although this varied between countries. Around 30 to 40 percent of Japanese and Chinese have the gene, and almost double that in Korea. The study found the levels to be 10 percent in Caucasians and seven percent in Hispanic populations.

The BJSM, like the Swedish scientists, also recommended that athletes should have an “endocrinological passport” to prevent them exploiting the gene loophole.

Ayotte echoes this: “The best way forward would be to have subject base profiles.”

She explained that much like the biological passports common in sports like cycling, where an athlete’s blood is monitored over years, base profiles would flag up individual’s genetics that could be relevant.

David Epstein is an American expert on genetics in sport and the author of The Sports Gene, which delves into various ways that genetics influence sporting ability.

“If we really wanted to be technologically savvy about drug-testing, we’d have to have genetically personalised testing,” he told The Mail on Sunday. “If I were an athlete bent on cheating, and I was aware of that gene, I would certainly get tested for it (to confirm an advantage on the testers).

“If I were doing the drug testing, I’d want to do carbon isotope ratio testing on everyone, to get around this problem and look straight for synthetic testosterone, but that test is costly and infrequently done.”

Official Wada statistics show that certain major accredited labs in some Asian countries are returning many fewer negatives than counterparts elsewhere.

Of 267 000 drugs tests conducted globally last year, 1.19 percent had “adverse” findings – or were positive – with a further 0.57percent “atypical” and needing further investigation.

Rates of adverse findings were broadly in line with this at London’s major laboratory (0.74 percent adverse findings), and in Sydney (0.76 percent), Paris (1.97 percent) and Stockholm (0.14 percent). But the corresponding numbers in Tokyo were 0.16 percent, 0.34 percent in Beijing and 0.48 percent in Seoul.

It is impossible to know how many athletes are doping but passing tests because they have the “impunity” gene. It may just be coincidental that laboratories in the regions where the gene is most common are finding fewer cheats. Or it may not. - Daily Mail