The debate over anti-doping at the Tour de France has focused on the controversial late-night tests that woke riders like Tadej Pogačar and Jonas Vingegaard over the weekend. But one of cycling’s leading anti-doping experts says the sport could soon face a much bigger problem: gene doping.
How does/would gene doping work?
Peter Van Eenoo, head of the DoCoLab anti-doping laboratory in Ghent, told Dutch television program De Avondetappe that advances in gene therapy could eventually be adapted to enhance athletic performance, creating a new challenge for anti-doping authorities.
It’s not the first time there have been about something that sounds almost science fiction. WADA has had it on its radar over 20 years ago, but according to some, it could very well be a reality, or become one.
Unlike traditional drugs such as EPO, gene doping works by introducing genetic material that prompts the body to produce its own performance-enhancing substances, making it much harder to detect with existing testing methods. If used in cycling, or, well any endurance sport, it could potentially be done well before a race, with the body continuing to produce the desired proteins for weeks or even months.
That’s a plus if you’re doping; there’s no need to sneak in needles, blood bags or centrifuges like in the bad old days of the Festina Affair, Operación Puerto or the Lance Armstrong era. It would also leave far less physical evidence for investigators to find during a raid or anti-doping operation. That’s clutch if you’re gonna cheat.
Understanding genetic modification
“You introduce or modify genetic material,” Van Eenoo said Van Eenoo said on De Avondetappe, as reported by WielerFlits. “People used to think that meant changing DNA itself, but it doesn’t have to be that drastic. The COVID-19 vaccines, for example, are a form of gene therapy using mRNA.”
He warned that similar technology could theoretically be used to trigger the body to produce EPO or Human Growth Hormone (HGH.)
“My fear is that the same methodology that worked so well during the pandemic could one day be used as a new doping method,” he said. “We have three ways of detecting doping, but we don’t know whether we’re ready for this form.”
Fallout after the late-night testing
The comments come just days after the Tour was rocked by criticism of overnight anti-doping controls. Riders, teams and the Cyclistes Professionnels Associés (CPA) questioned the practice after several riders, including Pogačar and Vingegaard, were tested in the middle of the night. “Our position is clear that the CPA is extremely disappointed with the current direction of anti-doping in professional cycling,” the union said in a statement.
After the Dane crashed out of the Tour, many wondered if his lack of sleep–Vingegaard was woken at 2 a.m., might have contributed to decreased focus. Even the yellow jersey wondered that. But, the good ole UCI defended the tests, saying they are only carried out under very specific circumstances.
UCI weighs in on late-night doping tests at Tour de France
Van Eenoo said gene doping differs from conventional doping because the substance introduced into the body disappears quickly, while the biological effects can last for months.
“With traditional doping, you introduce products that are active themselves,” he said. “Here, you introduce something that your body uses to make those products. The genetic material may disappear within a few days, but the process it starts can continue for months.”
Is it testable?
He noted that gene doping would not be completely invisible. Abnormal changes could still appear in an athlete’s biological passport. So in theory, anti-doping officials would have indirect way to spot suspicious activity. However, he did say that indirect evidence is less powerful than directly identifying a banned substance such as EPO or testosterone.
Asked whether gene doping is already possible today, Van Eenoo didn’t exactly rule it out.
“I don’t dare say no,” he said. “That would be very naïve. I suspect not, but I’m not certain. It would be very difficult for an individual to do, but I think it could be within the capabilities of certain countries.”
As we’ve seen in the past, dopers have often been one step ahead of the testers. The recent run of controversial late-night controls at the Tour, and Pogačar’s comment that 2026 has been “a weird year” for testing, shows just that anti-doping may even be evolving, even as experts warn the next challenge could be something entirely different. The test in the middle of the night though, were apparently looking for something different–and seemingly “dated”: microdosing of stuff like bloodboosters or testosterone.
If done far in advance of the actual test after the race, there would be no evidence. It was what many riders used to cheat 20 years ago.
But still, it should be noted despite all these rumours, there has been zero evidence in pro cycling, or any endurance sport, is using any kind of gene doping.
Either way, the Tour rolls on. Since the controversial tests of Pogi and Vingegaard, several more riders have been tested, including Paul Seixas, according to Cycling Weekly. In fact, apparently the entire peloton was tested and had their biological passports updated on Monday.