Note: Complete female sexual development requires absence of all the above-mentioned factors/hormones: TDF, testosterone, DHT, and MIF. In a rare case of loss-of-function mutation in SRY gene, there is absence of all the above-mentioned hormones/factors (leading to female internal and external organs in an XY genotype fetus). They also have failure of ovaries to develop, resulting in streak gonads (ovaries). This is called gonadal dysgenesis (a.k.a. Swyer syndrome).

^aComplete androgen insensitivity syndrome is an X-linked mutation that results in defective androgen (testosterone/DHT) receptors that do not respond to androgens. Note: Genetic females (XX genotype) are carriers of this disease.

^bIt is a type of congenital adrenal hyperplasia. Note: In genetic females (XX genotype), deficiency of estrogen (due to decreased conversion of testosterone into estrogen) leads to failure/delay of sexual development (e.g., primary amenorrhea with ultrasound [US] revealing uterus).

^a,b Presentation: an apparently normal phenotypically female fails to have menarche, and is found to have a blind vaginal pouch.

^cGonadectomy is recommended in cryptorchidism, as there is increased risk of dysgerminoma and gonadoblastoma. When to do gonadectomy? Wait until puberty (benefits of waiting until puberty for attainment of adult height likely outweighs gonadoblastoma risk).

^dIn less severe forms, external genitalia can be ambiguous or have decreased virilization of male parts (e.g., partial androgen insensitivity syndrome, incomplete 5-alpha-reductase deficiency or mild 17-alpha hydroxylase deficiency). The less severe forms are harder to make a diagnosis.

^e Mutation in 5-α-reductase

Note: In genetic females (XX genotype) this has a subtler impact—e.g., delayed menstruation. Testosterone to estrogen conversion occurs in this case. In males, they might have blind vaginal pouch, or ambiguous genitalia with micro-penis.

^fDefective embryogenesis resulting in absence of or very small Müllerian structure. They are phenotypically normal female with functioning ovaries and normal female hormonal levels. They present with amenorrhea (as no uterus) and a short vagina.