False-positive cases in detection of testosterone doping

Genetic aspects of epitestosterone formation and androgen disposition: influence of polymorphisms in CYP17 and UGT2B enzymes

“…polymorphism and the low EG excretion in the A1/A1 participants may partly explain why some individuals have naturally elevated ( > 4) T/E ratios [5][6][7][8]. This is of interest because falsely positive doping test results are of great concern for the legal rights of the sportsman.…”

“…The deletion polymorphism is six times more common in a Korean compared with a Swedish population [4]. There are also individuals that have naturally higher T/E ratios than 4 [5][6][7][8], most likely because of decreased excretion of EG [5,7]. The reason behind low levels of urinary EG is unknown.…”

Fortnightly Review: Drugs in sport

“…β11 Agonists used systemically also have powerful anabolic effects, hence clenbuterol is banned. Other β12 agonists are also prohibited, though salbutamol, salmeterol, and terbutaline, which are prohibited for systemic use, are permitted by inhalation if previously declared.…”

“…β11 Agonists used systemically also have powerful anabolic effects, hence clenbuterol is banned. Other β12 agonists are also prohibited, though salbutamol, salmeterol, and terbutaline, which are prohibited for systemic use, are permitted by inhalation if previously declared. Doubts remain about the possibility of false positive test results,11 and indeed a recent paper examined the effect on drug tests of eating meat from steroid treated livestock 12…”

On the origin of physiologically high ratios of urinary testosterone to epitestosterone: consequences for reliable detection of testosterone administration by male athletes

“…Although the average ratio of testosterone to epitestosterone glucuronides (TG/ EG) found by several laboratories was between 0-9 and 1-6 in a population of healthy men and male adolescents (Donike et al 1983, Dehenmn & Scholler 1990, Kicman et al 1990, Carlström et al 1992, it has been reported that, in some rare cases, normal male individuals may have TG/EG ratios exceeding the threshold value without any supply of exogenous testosterone (Namba et al 1989, Oftebro 1992, Raynaud et al 1992, Dehennin & Matsumoto 1993. Some complementary criteria have therefore been suggested, such as the urinary TG/ luteinizing hormone (LH) ratio (Kicman et al 1990) and the serum testosterone/17-hydroxyprogesterone ratio (Carlström et al 1992).…”