“…Previous studies concluded that 5 ␣ -reductase deficiency constitutes to be one of the 2 major underlying etiologies among Egyptian patients with 46,XY DSD [Mazen et al, 1996;Gad et al, 1997]. Apart from large patient cohorts in the Dominican Republic, New Guinea and Turkey [Imperato-McGinley et al, 1974, 1991Akgun et al, 1986], the disorder, in general, has been rarely reported in other populations. In contrast, the number of Egyptian cases, originating from various geographical locations within the country [El-Awady et al, 1989;Mazen et al, 1996Mazen et al, , 2003Essawi et al, 1997;Gad et al, 1997], is large.…”