- Even as a newborn, he had bulging muscles that attracted
the attention of curious doctors. By the time he was 4, he could lift almost
seven pounds with each hand, with his arms fully extended -- something
adults can find difficult.
-
- There was something so innocent in the baby Popeye pictures
published this summer in the New England Journal of Medicine, along with
details about the genetic mutation that explains the German boy's extraordinary
strength. (It has nothing to do with spinach.)
-
- But there was nothing innocent in the buzz his strong
arms and legs created in the athletic world. It had little to do with the
fact that the baby, whose mother is a former professional sprinter, has
the potential to be a future champion.
-
- The ugly truth is that the German super baby may offer
a genetic template for cheaters of the future. By the time he is 20, Olympic
athletes may be genetically modified to grow muscles like his.
-
- Forget about the next generation of steroids or growth
hormones. Researchers say the future of cheating is athletes who have been
genetically altered so that their bodies produce performance-enhancing
substances on their own.
-
- Many experts believe that the first genetically modified
athletes could be competing at next Summer Olympics.
-
- "I would think the Beijing Olympics may be the time
to pick it up on a widespread basis," says Geoffrey Goldspink, an
expert in muscle regeneration at the University College Medical School
in London. He is already working on a test to detect genetic cheaters for
the U.S. anti-doping agency.
-
- The technology for gene therapy already exists. It involves
using viruses to deliver new genetic instructions that become incorporated
into muscle or other tissue and change the way they work. It has already
been used in several labs around the world to create super-muscular rodents,
dubbed mighty mice or Schwarzenegger mice. In many cases, the new genes
often don't work all the time -- only when researchers deliberately turn
them on by a simple action such as rubbing a leg muscle.
-
- Some, including Dr. Goldspink, suspect that the practice
-- dubbed gene doping -- is already being used in thoroughbred horse racing.
-
- In humans, experts say, the only issue is safety. This
means that there is a good chance that in a private lab somewhere in the
world, researchers are getting ready to make a performance-enhancing addition
to an athlete's DNA.
-
- The World Anti-Doping Agency, led by Canadian Dick Pound,
has pronounced that gene doping is cheating and has added it to the list
of banned substances and methods for Olympic athletes.
-
- Still, many athletes and their coaches are avidly following
the latest scientific developments, which have been made by doctors hoping
to find cures for muscle-wasting diseases such as muscular dystrophy or
for blood disorders such as anemia.
-
- When H. Lee Sweeney, a professor of physiology and medicine
at the University of Pennsylvania, first used gene therapy to create super-muscular
mice in 1998, he was swamped by e-mail messages from athletes and coaches
wanting to use his discovery to improve athletic performance. One request
came from a high-school football player who wanted to inject all the kids
on his team.
-
- They were excited by the news that Dr. Sweeney had found
a way to inject a gene into rats and mice that instructs their bodies to
make a hormone called insulin-like growth factor. The mice also take part
in an exercise program, and after two months, they can lift 30 per cent
more weight and have a third more muscle mass than normal mice.
-
- Dr. Sweeney is still years away from testing his discovery
in humans, but that didn't seem to matter to the would-be athletic guinea
pigs who contacted him offering to volunteer.
-
- Given the level of interest, and the millions of dollars
at stake for those competing for Olympic gold in high-profile sports, the
fact that gene therapy has so far proved risky for humans is probably not
a deterrent for some athletes.
-
- At the University of Pennsylvania, where Dr. Sweeney
works, 18-year-old Jessie Gelsinger died in 1999 after receiving experimental
therapy for an inherited liver disease that was treatable with drugs and
diet.
-
- For reasons researchers don't understand, the virus used
to deliver the DNA they hoped would cure the young man caused his fever
to run dangerously high. His major organs began to shut down, and his father
made the decision to take him off life support.
-
- Two "bubble boys" in France were successfully
injected with genes to build their non-existent immune systems, but later
developed leukemia.
-
- Setting the safety issue aside for a moment, genetically
altered athletes raise interesting ethical questions. In the years to come,
gene therapy may not have the same Frankensteinian overtones it has now.
It may turn out to be the best way to save the lives of patients with serious
diseases, or even to help heal sports injuries such as torn muscles.
-
- It is clear simply by looking at the bodies of many gold-medal
Olympians that they have a natural genetic advantage.
-
- In 1964, Finnish cross-country skier Eero Mantyranta
was suspected of blood doping after winning two gold medals because he
had so many red blood cells in his system. Three decades later, he was
cleared when researchers found that he and many of his family members have
a genetic mutation that increases their red-blood-cell count by 20 per
cent.
-
- Is it so wrong for athletes without this kind of extraordinary
natural capacity to want to level the playing field?
-
- It's cheating, says Mr. Pound, head of the World Anti-Doping
Agency. At a recent meeting of the American Association for the Advancement
of Science, he suggested that regulators not approve clinical trials for
gene-transfer therapy unless the scientists have developed a way to detect
if the procedure has taken place. He urged researchers developing gene
therapies that might have athletic applications to work on detection methods.
-
- Dr. Goldspink is happy to help. He is developing a test
to look for traces of the viruses scientists would use to deliver new DNA
into an athlete's body. Those viruses have been altered so they don't cause
disease, and so can be detected, he says. All that would be required would
be a scraping of cells from inside an athlete's mouth. "We've got
the techniques."
-
- Others researcher, including Dr. Sweeney, argue that
it won't be that easy to catch genetic cheats and may require invasive
tests such as muscle biopsies, which wouldn't be practical at the Olympics.
-
- Dr. Goldspink says it makes him feel better to try. After
all, it bothers him to think that a lifetime of work designed to prevent
muscle wasting in the sick or the elderly might help a sprinter gain an
advantage over a competitor.
-
- It is true, he says, that many elite athletes already
have a natural genetic advantage over some of their competitors. For example,
the ancestors of Kenyan long-distance runners needed to be able to cover
a lot of ground at great speed to keep track of their cattle and stay out
of the jaws of predators.
-
- "Why can't other athletes do what evolution had
done for the Kenyans over thousands of years, but speed it up by injections
and genes?" Dr. Goldspink says. "I think, once you open that
door, the whole thing becomes meaningless. It all comes down to who has
access."
-
- Others disagree.
-
- Andy Miah, a lecturer at the University of Paisley in
Scotland and author of the book Genetically Modified Athletes: Biomedical
Ethics, Gene Doping and Sport, says it is wrong to ban gene doping without
a broad, social debate.
-
- "What is the rationale for banning genetic modification?
If we are concerned about fair play, then actually gene doping might promote
fairness. If we are concerned about health, then getting the technology
right could actually be safer for athletes than current forms of doping,"
he says.
-
- He argues that Mr. Pound and the World Anti-Doping Agency
have acted precipitously in lumping genetic modifications in with taking
steroids or growth hormones.
-
- No question, there are going to be some blurry lines
to define. What, for example, is the difference between an athlete who
was selected as an embryo in a lab for genes that would make her a good
sprinter and one who is modified as a teenager to have the same advantage?
-
- Researchers are already studying the genetics of strong
athletes. In the United States, scientists have recruited 900 subjects
in a bid to find which genes predict who will have a muscular body and
who is doomed to get sand kicked in their face at the beach.
-
- Volunteers are asked to lift a weight with their weakest
hand, and then to lift weights with that arm twice a week for three months.
The researchers then look at the genes of the 10 per cent of subjects who
bulked up after the training, and the 10 per cent who stayed pretty scrawny.
So far, they've identified 25 different genetic differences between the
two groups.
-
- It is not hard to imagine the day when genes for athletic
prowess can be screened for, either in sperm, eggs, embryos or children.
-
- Mr. Pound, for now, is focusing on athletes who choose
to become genetically modified. He has warned that if the practice becomes
widespread, and goes undetected, it will be the end of sports as we know
it.
-
- "I want human beings," he told the American
Association for the Advancement of science. "Not mutants."
-
- How to do it
-
- Scientists willing to overlook serious safety concerns
could inject new genes into muscle or other tissue in an athlete's body.
Viruses would be used as the delivery vehicle, a way to get the new genes
into cells.
-
- This is a localized approach to genetic engineering.
Egg or sperm cells would not be altered, which means that the changes would
not be passed on to any offspring produced by a genetically altered athlete.
-
- Here are a few of the possibilities for using gene therapy,
also known as gene doping, to build a winning athlete:
-
- Boosting red-blood-cell production. In our bodies, a
protein called erythropoietin, or epo, regulates the production of red
blood cells, which carry oxygen to our muscles. The more epo you have,
the more red blood cells you make. Cheaters are already using a synthetic
version of epo designed to treat anemia. Researchers are working on injecting
a gene that would allow the body to make far more epo than normal, without
thickening the blood with too many red blood cells. This would help patients
with blood disorders, as well as cyclists, runners and other long-distance
athletes.
-
- Encouraging muscle repair and growth. Insulin-like growth
factor, also known as IGF-1, is produced by our bodies and repairs the
everyday damage caused to muscle fibres when they are used. Cheaters are
now orally taking versions of IGF-1. Researchers in the United States have
turned normal mice into super rodents by injecting the gene for IGF-I directly
into their muscles. Other researchers are working on other even more effective
growth factors, including one called mechano growth factor. Their work
could help people with muscular dystrophy and other muscle-wasting diseases,
as well as sprinters and weightlifters.
-
- Removing the natural check on muscle growth. Myostatin
is a protein that regulates muscle growth in normal humans. The New England
Journal of Medicine recently reported that a German baby born with bulging
muscles had a mutation that blocked the production of myostatin. Researchers
may be able to do the same thing for athletes through gene therapy. This
could help sprinters, weightlifters and football players.
-
- - Anne McIlroy is The Globe and Mail's science reporter
-
- © Copyright 2004 Bell Globemedia Publishing Inc.
All Rights Reserved.
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