Sex-determining Region Y in Mammals

The Sex-determining Region Y (Sry in mammals but SRY in humans [4]) is a gene found on Y chromosomes that leads to the development of male phenotypes, such as testes [5]. The Sry gene, located on the short branch of the Y chromosome, initiates male embryonic development in the XY sex determination [6] system. The Sry gene follows the central dogma of molecular biology; the DNA encoding the gene is transcribed into messenger RNA, which then produces a single Sry protein. The Sry protein is also called the testis-determining factor (TDF), a protein that initiates male development in humans [4], placental mammals, and marsupials. The Sry protein is a transcription factor that can bind to regions of testis-specific DNA, bending specific DNA and activating or enhancing its abilities to promote testis formation, marking the first step towards male, rather than female, development in the embryo.