London - The London Olympics may turn out to be one of the cleanest in history in terms of banned substances, but behind the scenes, scientists fear the next big challenge to fair play in sport – gene doping.
Over the past decade, scientific advances in the understanding of how genes control muscle activity have alarmed experts within the World Anti-Doping Agency (Wada). They believe using genes, rather than drugs, will be the next way to illicitly boost athletic performance without fear of detection.
Although scientists are unanimous in believing genetically enhanced athletes did not participate in London 2012, they are almost equally unanimous in saying there will be an attempt to misuse the technology in a future Olympics.
“We don’t have any evidence [of current gene doping],” says Professor Steve Harridge, an expert on muscle physiology at King’s College London.
“But in the future, as gene-therapy techniques become more refined, it becomes more likely, although I think we are many years away from that.
“The attraction of gene doping is that it is much harder to detect. But there are dangers because you don’t know what it is going to keep on doing. The overall control of muscles can be brutally changed by the sudden introduction of a gene.”
Other experts believe gene doping will not be so easily dismissed as too difficult or risky by those who are prepared to go to physical and ethical extremes to win medals.
“We don’t know that gene doping would work, but it’s technically feasible,” says sports ethicist Professor Andy Miah, the director of the Creative Futures Research Centre at the University of the West of Scotland. “If you look at the investment of Wada over the past 10 years, this is their key issue. It’s hard to argue with the view that is real in a lot of sports.”
Wada defines gene doping as the non-therapeutic use of genes to enhance athletic performance. The Montreal-based agency, set up in 1999, has spearheaded a campaign to develop scientific methods of detecting its illicit use in sport.
The issue took off in 2004 after the publication of studies by Dr Lee Sweeney of the University of Pennsylvania, showing it was possible to create genetically modified (GM) mice with enhanced genes for producing a natural stimulant called insulin-like growth factor (IGF-1) in their muscles.
The enhanced genes increased the mice’s muscle strength by 30 percent or more, enabling them to run faster and longer on treadmills compared with ordinary mice.
Sweeney was almost immediately swamped by enquiries from athletes who wanted to get their hands on the technology. It was evident this type of research was seen as the next possible stage in the continual evolution of sport doping.
At the time, Sweeney said the availability of this technology for human use was not going to be anytime soon, but the temptation for organisations in some countries with the resources and know-how might be too great to resist.
“One can imagine with enough money you could put together a programme to genetically engineer your athletes in such a way it would be undetectable unless you were to remove tissue from that athlete.” There would be no signature in the blood or runing to indicate genetic manipulation.“
The GM mice in Sweeney’s experiment were modified as embryos. Such “germ-line” gene therapy, where genes in every cell of the body are altered, is banned in Britain and many other countries.
But Wada is concerned about the possibility of adapting gene-therapy technology used in legitimate medicine to modify specific tissues of athletes, such as leg muscles, even though clinical trials on patients have proved largely ineffective and even dangerous.
In 2005, Wada held an international gene doping symposium in Stockholm, where it became clear this was the key new area of interest.
“Gene doping will in all likelihood soon be with us, and I would not be surprised if the first tentative steps had already been taken,” said Professor Theodore Friedmann of the University of California, San Diego.
“The genes are available and you make them. All it takes is three or four well-trained post-docs [post-doctoral students] and a million or two dollars,” says Friedmann, the chairman of Wada’s gene-doping panel and a world authority on genetic engineering.
Since Sweeney’s pioneering work of 2004, several further studies have shown it is possible to tweak other genes involved in the metabolic pathways affecting muscle performance.
In 2006, US scientists at Dartmouth College in New Hampshire showed it was possible to produce GM mice with a liver gene in their muscles for a substance called AMPK, which boosts concentrations of glycogen, a natural store of chemical energy.
These GM mice ran three times as long as ordinary mice without suffering exhaustion.
And in 2008, scientists at the University of Pennsylvania created GM mice that could run six times further, simply by altering a gene called interleukin-15R alpha, which shifts how energy is used in “fast-twitch” muscle fibres.
In the same year, the Salk Institute in California demonstrated how genes and environment could interact in unexpected ways to enhance athletic performance by taking drugs that “turbocharged” specific performance-enhancing genes. – The Independent