Although CAIS is the most common form, resulting in feminization of a 46, XY fetus, there are other syndromes one must consider: SRY gene mutations, 5-α reductase deficiency, Swyer syndrome, 17-α-hydroxylase deficiency, and Smith-Lemli-Optiz syndrome.9 This evidence concerns the gene SRY and 46,XY complete gonadal dysgenesis.