SRY, sex determination and gonadal differentiation

The commitment to develop into a male or female embryo is dependent on whether testes or ovaries develop from the primordial gonads. This decision is in turn controlled by the function of a gene, SRY, found on the Y chromosome in mammals. The proper expression and function of SRY in supporting cell precursors induces a cascade of gene expression that causes these cells to differentiate into Sertoli cells. Subsequently, Sertoli cells orchestrate the development of all other cell types resulting in the formation of testes, which produce hormones required for other aspects of male development. In the absence of SRY, or if SRY function is impaired, the supporting cells differentiate into granulosa cells, ovaries form and the embryo develops as a female