杏吧原创

Biological passport to catch sports cheats

The composition of an athlete's blood can now be used as evidence of illegal doping, even if no substance is found
Speed skater Claudia Pechstein was banned for two years
Speed skater Claudia Pechstein was banned for two years
(Image: Matt Dunham/PA)

ATHLETES be warned: the way illegal doping is detected is on the cusp of a radical change.

On 2 December, the World Anti-Doping Agency (WADA) released on the long-awaited 鈥渁thlete biological passport鈥, a way to spot cheats by monitoring them for suspicious changes in normal physiology. The method would be used in addition to testing for specific drugs.

The passport, which consists of a regularly updated record of blood measurements for each athlete, was first suggested in 2002 and is already being piloted by several sports federations, including the International Cycling Union (UCI).

The release of the guidelines, which specify for the first time what measurements should be documented in the passport (see chart), may speed its uptake by many more. 鈥淭hese guidelines are to help sporting federations everywhere introduce biological passports,鈥 says , a WADA adviser at the University of Freiburg in Germany.

What's in the blood

Meanwhile, a similar method already used by the International Skating Union (ISU) has resulted in a guilty verdict, a first for this kind of monitoring. After some unusual blood-cell readings, German speed skater Claudia Pechstein has been banned from competing for two years. 鈥淚t鈥檚 a very important legal precedent,鈥 says Enrico Carpani, spokesman for the UCI in Aigle, Switzerland.

As with any new method, there is the possibility of mistakenly accusing athletes who have done nothing wrong 鈥 or missing those who have. The challenge for WADA is to show the passports limit the likelihood of this. 鈥淲e must protect clean athletes, and make sure we don鈥檛 incriminate them through false positives,鈥 says Schumacher.

The agency is hoping for widespread adoption of the passports on a trial basis because of their potential power. Crucially, biological passports have the ability to detect signs of doping without identifying specific substances, which can be elusive. They might also detect doping that doesn鈥檛 involve illegal substances but produces measurable effects on the body, such as blood transfusions or gene doping. 鈥淓very reading is retained, so the passport never forgets,鈥 says Schumacher.

In Pechstein鈥檚 case, this power appears to have been demonstrated. The ISU detected spikes in the proportion of Pechstein鈥檚 blood cells that were reticulocytes, young red blood cells recently released from bone marrow. Normally, about 1 per cent are reticulocytes, but the proportion climbs to 3 per cent following doping with substances such as the hormone erythropoietin (EPO), and falls as low as 0.5 per cent if people have had transfusions.

The ISU accused her of illegally enriching her blood. Pechstein claimed the abnormal counts were because of a blood disease, and appealed the decision.

There are natural causes for altered reticulocyte count, such as anaemia, but last month the Court of Arbitration for Sport, the world authority for adjudication on doping cases, . It rejected Pechstein鈥檚 claim that she had a blood condition after a haematologist chosen by her was unable to find any signs of disease.

The UCI, which has been for the past two years on 840 cyclists in Italy and Spain, expects verdicts on by February 2010. 鈥淲e鈥檙e very happy with the passport,鈥 says Carpani.