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Sex-dependent toxoplasmosis-associated differences in testosterone concentration in humans

Published online by Cambridge University Press:  21 January 2008

Department of Parasitology, Faculty of Sciences, Charles University, Viničná 7, 128 44Prague 2, Czech Republic
Department of Parasitology, Faculty of Sciences, Charles University, Viničná 7, 128 44Prague 2, Czech Republic Department of Anthropology, Faculty of Humanities, Charles University, Prague, Husníkova 2075, 155 00, Prague 13, Czech Republic
National Reference Laboratory for Toxoplasmosis, National Institute of Public Health, Šrobárova 48, 100 42, Prague 10, Czech Republic
*Corresponding author: Department of Parasitology, Faculty of Science, Charles University, Viničná 7, CZ-128 44 Praha 2, Czech Republic. Tel: +420 221951821. Fax: +420 224919704. E-mail:


Several lines of indirect evidence suggest that subjects with latent infection of the coccidian parasite Toxoplasma gondii have a higher concentration of testosterone than uninfected controls. Here, we searched for direct evidence of latent toxoplasmosis-associated differences in testosterone concentration among a population of 174 female and 91 male students screened for Toxoplasma infection. We have found Toxoplasma-infected men to have a higher concentration of testosterone and Toxoplasma-infected women to have a lower concentration of testosterone than Toxoplasma-free controls. The opposite direction of the testosterone shift in men compared to women can explain the observed gender specificity of behavioural shifts in Toxoplasma-infected subjects.

Original Articles
Copyright © Cambridge University Press 2008

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