Regulation of zebrafish gonadal sex differentiation

While the master regulator gene Sry on the mammalian Y chromosome controls the switch for initiating male sex differentiation, many other species rely on environmental factors for gonadal sex differentiation. Yet other species, like zebrafish, appears to rely on a multitude of genetic cues for gonadal sex differentiation. Zebrafish gonadal differentiation initiates with the onset of a juvenile ovary stage and depending on the influence of unknown genetic factors either maintains oocyte development or initiate apoptotic processes to override the female differentiation pathway. In this review, we explore the role of different factors and genes that have been reported to influence zebrafish gonadal sex differentiation. We also give a brief insight of primordial germ cell (PGC) involvement in shaping male and female signaling pathway in gonadal development.