Detection of testosterone doping in female athletes

Abstract

Testosterone doping remains a prevalent and potent form of drug cheating among elite athletes. In men, the urine testosterone (T) to epitestosterone (E) ratio (T/E ratio) can identify administration of exogenous T by its suppression of endogenous T production through strong negative feedback on endogenous T and E production as well as spill over into urine of extra testosterone. However, this mechanism may be partially inoperative in females whose much lower circulating T derives from three sources, none subject to powerful negative T feedback. Hence, additional methods to detect T doping in females are required. In this study we report two cases of elite female athletes who were sanctioned for T doping proven by measurement of serum T using liquid chromatography−mass spectrometry (LC–MS), when serial urine T and T/E ratio in one were not indicative of T doping, and in the other were nullified by incidental genetic inactivation of T glucuronidation through the uridine diphosphoglucuronosyl transferase 2B17 (UGT2B17) deletion genotype–phenotype. These findings indicate the potential for serum T measurement by LC–MS to detect T doping in female athletes, especially if implemented in the Bayesian format of an athlete biological passport.

Studies of athlete biological passport biomarkers and clinical parameters in male and female users of anabolic androgenic steroids and other doping agents

“…The results indicated that dermal testosterone use in women is not detectable with the traditional T/E biomarker, despite supra‐physiological total testosterone serum concentrations. This is in line with a recent publication showing that elevated serum testosterone concentrations in two elite female athletes did not result in elevated urinary T/E ratios in their ABPs . Since our study and the study conducted by Handelsman et al are both based on case observations, there is an urgent need to perform a controlled study in relation to transdermal testosterone administration in women.…”

“…This is in line with a recent publication showing that elevated serum testosterone concentrations in two elite female athletes did not result in elevated urinary T/E ratios in their ABPs. 12 Since our study and the study conducted by Handelsman et al are both based on case observations, there is an urgent need to perform a controlled study in relation to transdermal testosterone administration in women. It is possible that longitudinal monitoring of the ABP biomarkers in our participants rather than single urine sampling would have resulted in atypical findings.…”

“…Individuals devoid of the UGT2B17 gene (del/del) excrete negligible amounts of testosterone in the urine and rarely reach the T/E cut‐off value of 4 after testosterone doping . Notably, the urinary T/E ratio was not sensitive when supra‐physiological serum testosterone concentrations were detected in female athletes, most likely induced by testosterone intake . Therefore, it may be informative to include longitudinal serum testosterone levels in the ABP in the future.…”

“…11 Notably, the urinary T/E ratio was not sensitive when supra-physiological serum testosterone concentrations were detected in female athletes, most likely induced by testosterone intake. 12 Therefore, it may be informative to include longitudinal serum testosterone levels in the ABP in the future. Monitoring steroid hormones, e.g.…”

Longitudinal studies of putative growth hormone (GH) biomarkers and hematological and steroidal parameters in relation to 2 weeks administration of human recombinant GH

“…Today the ABP includes a steroidal and a hematological module, of which the former includes the urinary concentrations of six steroid metabolites. The monitoring of the circulatory levels of steroids, especially testosterone (T) and dihydrotestosterone (DHT) has been suggested to enhance the sensitivity of detecting endogenous anabolic androgenic steroids 9,10 . The hematological ABP module includes parameters such as the reticulocyte percentage (RET%), hemoglobin (HGB), and an OFF‐score to determine whether blood doping or tampering with the blood has occurred 11,12 …”