SRY (Sex-determining region Y) is a sex-determining gene on the Y chromosome in the therians (placental mammals and marsupials).
This intronless gene encodes a transcription factor that is a member of the SOX (SRY-like box) gene family of DNA-binding proteins. This protein is the therian testis determining factor (TDF), referred to as the sex-determining region Y protein or SRY protein which initiates male sex determination. Mutations in this gene give rise to XY females with gonadal dysgenesis (Swyer syndrome); translocation of part of the Y chromosome containing this gene to the X chromosome causes XX male syndrome.
Read more about SRY: Molecular Biology of Testis Determination, Effect Upon Anatomical Sex, SRY and The Olympics, SRY-related Diseases and Defects, Evolution, Interactions