SRY and disorder of sexual differentiation: Approximately 45% of 46,XY DSD at the gonadal level can be attributed to loss-of-function mutations in the testis-inducing genes, SRY [3,44], SOX9 [45,46] or upstream regulators of SRY, such as SF1, GATA4 and MAPK [47,48,49,50,51,52,53].