LONDON - There have been "marathon mice", "Schwarzenegger
mice" and dogs whose wasted muscles were repaired with injected substances
that switch off key genes. It may not be long before we get the first
genetically modified athlete.
Some fear the use of gene therapy
to improve athleticism is already a reality. But since sports authorities' drug
testing methods still lack the sophistication needed to pick up gene doping,
its status remains unclear.
What is certain, from scientific
studies and from surveys of elite sports people, is that it is technically
feasible to use genetic modification to improve sporting performance, and that
some athletes are prepared to risk their lives if they could be guaranteed to
win gold medals.
Officially, UK Anti-Doping, the
body which oversees the control of performance enhancing drugs in Britain, says
genetic manipulation as a form of performance enhancement "is currently a
theoretical rather than a proven issue".
But Andy Parkinson, UKAD's chief
executive said: "I wouldn't be surprised if someone out there is trying to
do it, and I think that's very worrying."
The World Anti-Doping Agency
(WADA) says it is ploughing "significant" money and resources into
research into finding ways to detect genetic enhancement of athletes.
New Genetic Make-Up
Gene doping - in which DNA is
introduced into the body using an inactivated virus or by other means - could
alter a person's genetic make-up and improve athletic performance by increasing
muscle growth, blood production, endurance, oxygen dispersal or pain
perception.
Since it cannot be detected, no
one really knows whether athletes are using it or not.
Chris Cooper, a professor of
sports and exercise science at Essex University and author of a book called
"Run, Swim, Throw, Cheat" thinks it is "hugely unlikely anyone
is gene doping" and says the focus should be on people who use well-known
performance enhancers like anabolic steroids and blood doping.
However, emails that surfaced
during a trial of a German track and field coach Thomas Springstein in 2006
showed that people behind some athletes were at least thinking about genetic
modification as a way forward.
Scientists who lead the field in
developing gene therapy techniques in laboratory animals have also reported
being inundated with enquiries from sports people keen to know more.
"There are animal models
which show efficacy and the possibility of this being technically feasible for
an athlete to do," said Andy Miah, a bioethicist and director of the
Creative Futures Institute at the University of the West of Scotland.
The drug mentioned in the 2006
German court case was Repoxygen - a gene therapy developed by the British
biotech Oxford Biomedica as a treatment for severe anaemia.
The company has since pulled the
plug on developing the product as it seemed unlikely to be profitable as a
medicine.
Yet an email written by coach
Springstein to a Dutch doctor suggested some in the sports world were already
keen.
"New Repoxygen is hard to
get," Springstein wrote. "Please give me new instructions soon so
that I can order the product before Christmas."
Repoxygen is based on a direct
injection of an inactivated virus carrying the gene for EPO, or erythropoietin,
a hormone beloved by athletic dopers seeking to artificially boost their red
blood cells and aerobic capacity.
Marathon Mice
Repoxygen is just one of a number
of scientific developments that caught the eye of potential sports dopers.
Lee Sweeney, a professor at the
University of Pennsylvania in the United States, has pioneered research into
gene transfer technology and developed various super-sporty lab mice to test
its potential.
In 2007, while researching
possible ways to restore muscle growth in patients with muscular dystrophy,
Sweeney and his colleagues created mice in a lab who continued to have enormous
muscles and significant strength into old age.
The super mice were created by
injecting normal mice with a virus containing the gene for insulin growth
factor 1, or IGF-1, a protein that interacts with cells on the outside of
muscle fibres and makes them grow.
They were nicknamed
"Schwarzenegger mice" after the American bodybuilder and film
star-turned politician. Scientists later reported success in treating dogs with
wasted muscles with the same therapy.
These experiments followed hot on
the heels of "marathon mice", which hit the headlines in 2004 after
researchers genetically engineered the lab animals by tweaking a gene called
PPAR-delta.
The scientists found the
genetically engineered mice could run twice as far as normal mice, and they
stayed lean even when they were fed on a high-fat diet.
"So there's a technical precedent
for this (performance enhancing genetic modification), but it's still uncertain
quite how it would effect humans," said bioethicist Miah.
"And of course there are
uncertainties about how those animals are effected in other ways - does it
effect their fertility? Their longevity?"
In his book, Cooper relates the
tale of an experiment conducted by Jim Wilson, one of Sweeney's colleagues at
the University of Pennsylvania, who tested EPO gene therapy in macaque monkeys.
It initially worked as expected,
increasing oxygen transport in the monkeys' blood. But the high concentrations
of EPO soon produced so many red blood cells that the blood became like sludge
and needed to be thinned at regular intervals.
Then the monkeys' EPO levels
suddenly plummeted, leading to severe anaemia and forcing the scientists to end
the experiment and euthanise the animals.
"These studies show that of
all the doping techniques we are talking about ... gene doping is currently by
far the most technically difficult and risky to attempt," Cooper writes.
Gold Medals - To Die For?
Yet while such potentially
life-threatening and unknown side effects are a major concern for people
seeking to develop medicines to treat sick patients, would-be genetically
modified Olympians may take a different view.
Experts said that to evaluate
whether something as risky and unproven as gene doping is being tried in
sports, it's important to see just how far athletes might go in pursuit of gold
medals.
A frequently-cited survey in the
world of sport gives a bleak picture. In it, Chicago-based Bob Goldman, a
doctor and founder of the US National Academy of Sports Medicine, asked elite
athletes in the 1980s whether they would take an enhancement which guaranteed
them gold medals but would also kill them within five years. More than half
said yes.
"I was shocked to see that
out of 198 world-class athletes, 52 per cent would be willing to give up their
life for five years of an undefeated run of wins," Goldman told Reuters
during the 2004 Olympic Games in Athens.
He repeated the survey every two
years for the next decade and the results were always the same - around half of
the athletes polled were ready to die for gold. "Some of the athletes are
only 16-years-old," Goldman said. "To be willing to die at 21 is a
serious psychological mindset."
While no-one can be sure if
genetically modified Olympians are swimming in pools or running on tracks right
now, the lure of winning gold may make athletes more willing than most to take
a dangerous genetic leap into the unknown.
"That's partly why the world
of sport is so concerned," said Miah. "They know that if athletes had
something that would give them the opportunity to win medals, but would kill
them 5 years later, many of them would take it.
"This is a community of high
risk takers."
Kate Kelland
Reuters
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