A DNA-based method for detecting homologous blood doping.

Homologous (or allogeneic) blood doping, in which blood is transferred from a donor into a recipient athlete, is the easiest, cheapest, and fastest way to increase red cell mass (hematocrit) and therefore the oxygen-carrying capacity of the blood. Although thought to have been rendered obsolete as a doping strategy by the increased use of rhEPO to increased hematocrits, there is evidence that athletes are still using this potentially dangerous method to improve endurance performance. Current testing for homologous blood doping is based on identification of mixed populations of red blood cells by flow cytometry. This paper proposes that homologous blood doping could also be tested for by high-resolution qPCR-based genotyping and demonstrates that assays could be developed that would detect second populations of cells even if the "donor" blood was depleted of 99% of the DNA-containing leukocytes. Issues of test specificity and sensitivity are discussed as well as some of the ethical considerations that would have to be addressed if athletes' genotypes were to be used by the anti-doping authorities to prevent, or detect, the use of prohibited ergogenic practices.