Free Access
Reprod. Nutr. Dev.
Volume 44, Number 6, November-December 2004
Page(s) 539 - 549
Reprod. Nutr. Dev. 44 (2004) 539-549
DOI: 10.1051/rnd:2004062

Sex determination: the amphibian models

Christophe Eggert

Laboratory of Alpine Ecology, UMR CNRS 5553, CISM, University of Savoie, 73376 Le Bourget du Lac, France

(Received 6 May 2004; accepted 15 September 2004)

Abstract - We review and discuss current knowledge about sex determination in amphibians. The astonishing wide variety of mechanisms of genotypic sex determination is presented and discussed in an evolutionary context. We recall the natural occurrence of transitory juvenile hermaphroditism in some species. Our present knowledge of the mechanisms of sex determination in amphibians is compared to that in mammals. The influence of epigenetic factors, and especially temperature is highlighted. In amphibians, the influence of temperature on sexual differentiation, that can prevail over genotypic sex determination, remains poorly considered in publications. We suggest that studies on genetic and epigenetic factors of gonadal sex differentiation in amphibians could provide substantial information on the evolutionary process of sex determination mechanisms in current living vertebrates.

Key words: sex determination mechanisms / sexual differentiation / hermaphroditism / epigenetic factors

Corresponding author: Christophe Eggert

© INRA, EDP Sciences 2005