The gene doping test is based on work by Anna Baoutina and
colleagues at the National Measurement Institute in Sydney,
Australia. The technique relies on the gene that naturally codes
for EPO in the human body and the fact that it contains four
introns, sequences that get cut out of messenger RNA after the
gene has been transcribed. Synthetic EPO DNA inserted during
gene therapy is unlikely to have such intron sequences. Gene
dopers could be caught if officials scanned blood samples for EPO
DNA without these introns.
This is not the only strategy proposed for checking athletes for
gene doping. Researchers have also designed tests that search for
proteins in blood that are unique to the viruses scientists use to
transport genes across a cell membrane and then into a genome
(Drug Testing Analysis 2012, DOI: 10.1002/dta.1347). Other techniques rely on looking at the sugars bonded to the exterior of the
protein (also known as “decoration”) that’s been produced from
the contraband. For example, EPO is normally produced in the
kidney, where it is glycosylated in four different places.
Gene dopers, however, are more likely to inject EPO DNA into
muscle, which has different glycosylation pathways. Unusual
sugar decorations could act as a smoking gun for gene doping,
Sundberg said. In fact, doping labs currently do an analogous test
that looks for athletes who have injected bacteria-synthesized
EPO directly into their blood, he added. Bacteria decorate EPO differently than humans do, giving testers a way to catch cheaters.
WADA is also funding research to test whether athletes have
received gene therapy for growth factor proteins, such as growth
hormone and IGF- 1, which bolster muscle development. The doping research field is also investigating ways to test for anticipated
cell doping in athletes, Sundberg said. Doctors have for a long
time transplanted bone marrow stem cells in cancer patients,
he said. “In the future, athletes may transplant cells to improve
heart and muscle strength and endurance.” And with the advent
of the CRISPR/Cas9 technique, athletes could start paying for
genetic editing of their own cells. “You might think it sounds like
a bit of science fiction, but it might quite soon not really be so,”
Although researchers are trying to anticipate future doping
strategies, steroids are currently still the number one choice for
doping athletes, Ljungqvist said at ESOF.
The spike in positive doping results that scientists saw when
they retested samples from Beijing and London, for instance,
can be attributed to steroids. Researchers have made improve-
ments in analytical instruments — primarily mass spectrom-
eters — for detecting contraband compounds, and they’ve
discovered so-called long-term metabolites of banned anabolic
steroids, including metandienone, oxymetholone, and stanozo-
lol, in athletes’ urine.
In the past, researchers could only detect metabolites of a
banned steroid in urine for weeks after the last dose, Ljungqvist
explained. “Now that window has been expanded to a couple of
months” with the identification of these metabolites that stick
around much longer.
After a WADA-accredited laboratory in Cologne, Germany,
started testing for long-term metabolites of metandienone, the
lab saw a 400% increase in positive doping results (Br. J. Sports
Med. 2014, DOI: 10.1136/bjsports-2014-093526).
Although most media attention focuses on doping by professional athletes, there’s also a growing doping problem among
the general public, Ljungqvist said.
“Nine-tenths of the iceberg underwater is the doping taking
place in recreational sports or by people trying to enhance their
body image in entirely unregulated ways,” said doping researcher
Mike McNamee from Swansea University to the ESOF delegates.
“It’s not just young men wanting to look like their favorite
Hollywood actor. It’s also policemen, firefighters, security personnel, and bouncers,” he said. Although everyone working in doping
agrees it’s a huge problem among the general public, there’s no
reliable prevalence data, McNamee said. Because it’s not possible
to test the general public for contraband drugs — except in Denmark, where doping officials are allowed to test people in public
gyms — education is probably the best way to reduce the use of
contraband drugs by the general public, McNamee added.
Of course, it’s hard to convince the general public not to use
contraband substances if professional athletes caught doping
don’t suffer consequences.
“I am one of those who was fooled in Sochi by the Russians,”
Ljungqvist told reporters during a press conference at ESOF. “At
night, behind my back, [they] were changing samples through
a hole in the wall. This is not the first time I was cheated by the
Russians. During the Beijing Games, we discovered that female
athletes’ urine was exchanged. This deserves some punishment.”
When asked about the IOC’s decision not to ban Russian athletes
from participation in Rio, Ljungqvist replied, “In the IOC report,
I would have welcomed an explanation about why this penalty
To read more from or subscribe to C&EN, visit cen.acs.org.
The original version of this article first appeared in the ACS weekly
newsmagazine, Chemical & Engineering News (C&EN). “Athletes at Rio
Olympics Face Advanced Antidoping Technology,” Chemical & Engineering
News, 2016, 94(32), pp 25-26. http://cen.acs.org/articles/94/i32/
“Although researchers are trying to anticipate future doping strategies,
steroids are currently still the number
one choice for doping athletes.”
“In the future, athletes may transplant cells to improve heart and
muscle strength and endurance.”