Biological passport

An athlete biological passport is an individual, electronic record for professional athletes, in which profiles of biological markers of doping and results of doping tests are collated over a period of time. Doping violations can be detected by noting variances from an athlete’s established levels outside permissible limits, rather than testing for and identifying illegal substances.

Although the terminology athlete passport is recent, the use of biological markers of doping has a long history in anti-doping. Maybe the first marker of doping, that tries to detect a prohibited substance not based on its presence in urine or blood, but through the induced deviations in biological parameters, is the so-called testosterone over epitestosterone ratio (T/E). The T/E has been used by sports authorities since the beginning of the 1980s to detect anabolic steroids in urine samples. A decade later, in 1997, markers of blood doping were introduced by some international federations, such as the Union Cycliste Internationale (UCI) and the Federation Internationale de Ski, to deter the abuse of recombinant erythropoietin that was undetectable by direct means at that time. It is only in 2002 that the concept of using biological markers to detect doping became known by the term athlete passport. The merits of this testing paradigm were exposed in the scientific literature and the terminology adopted by the World Anti-Doping agency.

Many believe that the athlete passport provides an excellent alternative to ensure fairness in elite sports. While a new drug test must be developed and validated for each new drug, the main advantage of the athlete passport is that it is based on the stability of the physiology of the human being. New drugs are produced at an unprecedented pace today and there is often a lag of several years between the availability of a new drug and the application of an effective detection method. In contrast, the physiology of the human being remains the same through several generations and all biomarkers developed today in the athlete passport will remain valid for at least several decades. For example, the blood module of the passport is already sensitive today to any new future form of recombinant erythropoietin, as well as to any form of gene doping that will enhance oxygen transfer to the muscles. Also, while a negative drug test does not necessarily mean that the athlete did not dope, the athlete can present his/her passport at the beginning of a competition to attest that he/she will compete in his/her natural, unaltered condition.

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Wikipedia