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How do maternal androgens and estrogens affect sex determination in reptiles with temperature-dependent sex?
Florencia E Valli1,2, Melina S Simoncini1,3, Marcela A González2
1CICYTTP-CONICET/Prov. Entre Ríos/UADER, Diamante, Argentina.
Abstract:
Temperature sex determination (TSD) in reptiles has been studied to elucidate the mechanisms by which temperature is transformed into a biological signal that determines the sex of the embryo. Temperature is thought to trigger signals that alter gene expression and hormone metabolism, which will determine the development of female or male gonads. In this review, we focus on collecting and discussing important and recent information on the role of maternal steroid hormones in sex determination in oviparous reptiles such as crocodiles, turtles, and lizards that possess TSD. In particular, we focus on maternal androgens and estrogens deposited in the egg yolk and their metabolites that could also influence the sex of offspring. Finally, we suggest guidelines for future research to help clarify the link between maternal steroid hormones and offspring sex.
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