October 20, 2013 - 5:34 AM
VANCOUVER - Researchers at the University of British Columbia have developed a DNA test to catch athletes who use blood doping to enhance their performance, but its limitations mean the current testing system will continue to detect cheaters.
James Rupert, an associate professor in the School of Kinesiology at the University of B.C., said the U.S. Anti-Doping Agency funded research for the DNA test, which was designed to be cheaper, easier and faster than the existing method.
The agency uses a test that examines athletes' blood for proteins to determine if they've received a transfusion of someone else's blood.
Rupert, whose study has been published in the journal Analytical and Bioanalytical Chemistry, said Friday that the UBC test allows DNA to be amplified to a high resolution, which can't be done with proteins.
He said the technology enables white cells to be inspected for different populations of genes and reveal if a second person's cells are present. Red blood cells do not have DNA.
Elite cheats, including admitted blood-doping cyclist Lance Armstrong, aim to boost their red blood cells, which carry oxygen from the lungs to the muscles, and help improve endurance.
However, Rupert said the initial quest was to develop a finger-prick test that could be used by volunteer doping control officers at the Olympics, for example, but it did not work.
He said there are also ethical concerns about collecting genetic data for doping control.
"There may be a bit of a block to collecting athletes' genetic data," he said.
The test may also be limited because of the various tricks athletes use to bypass blood-doping detection such as skimming off white blood cells before the blood is transfused from a donor.
"You'd take the blood out of somebody, you'd put it in a centrifuge and spin it and you extract the top layer of cells, which you can see. Then you'd just inject that into someone. It's not particularly challenging."
Rupert said the DNA test would not necessarily work on a small amount of diluted blood.
"The method we have is good enough if you actually had a mill of blood to detect (blood doping), even if they took out 99.9 per cent of the white blood cells. But with the finger prick there is just not enough material for it to work."
While a test for transfusions involving someone else's blood has existed for nearly a decade, there's no test for when athletes re-infuse their own blood, which happens in the majority of doping incidents because of the risks of using donor blood.
Dr. Larry Bowers, chief science officer for the U.S. Anti-Doping Agency, said the agency will examine ways in which the UBC research could contribute to its anti-doping testing.
However, Christiane Ayotte, head of the anti-doping lab at the INRS-Institute Armand-Frappier in Laval, Que., said the DNA test would therefore not be very useful.
Ayotte, who works at Canada's only lab accredited by the World Anti-Doping Agency, said donor blood is typically transfused into athletes by mistake "by crooked doctors with fridges full of blood bags."
She said the current technique has been well tested and accepted in court and there's no reason to change to something else.
"We already have the equipment, it has standing in courts and it's foolproof."
News from © The Canadian Press, 2013