By contrast, L724V, carried by a 46,XY DSD patient with a typical MAMLD1 phenotype (46,XY male with penoscrotal hypospadias and small penis), and the synonymous S730 mutation, found in 46,XY female patient (also with penoscrotal hypospadias and small penis), had only impaired CYP17A1 but normal Hes3 transactivation activity. This evidence concerns the gene HES3 and disorder of sexual differentiation.