Androgen insensitivity syndrome is an androgen receptor gene located on the long arm of the human X chromosome near the mitosis, containing eight exons encoding 910 amino acids, two zinc finger regions in the middle and an androgen binding region at the C-terminus. Mutations in certain parts of the gene can lead to androgen insensitivity syndrome or testicular feminization, in which individuals with karyotype XY develop into seemingly normal but infertile females, with the testes usually remaining in the abdominal cavity and without spermatogenesis. The androgen insensitivity syndrome is an X-linked recessive genetic disorder with karyotype 46,XY. It is a male pseudo-hermaphroditism, in which testosterone and urinary 17 ketones are normal male values, and the gonads in the body are testes. The result is vulvar feminization. Clinical typing: In 1976, Prader et al. classified patients with AIS (Androgen Insensitivity Syndrome (AIS)) into two categories, complete type without masculine manifestations and incomplete type with masculine manifestations, based on the presence or absence of masculine manifestations. 1. The patient may be seen in infancy for a labia majora or inguinal mass. Sometimes, during hernia repair, the contents of the hernia are found to be testicles. The clinical presentation is more consistent in adulthood: primary amenorrhea, female physique, pubertal breast development but breast androgen insensitivity syndrome, poorly developed complete head, absent or sparse pubic and axillary hair, female vulva, poorly developed labia majora and labia minora, blind end of vagina, absence of cervix and uterus, and no menstruation in artificial cycles. Gonads may be located in the labia majora, groin or abdominal cavity, and patients often present with primary amenorrhea, labia majora or inguinal masses. During the embryonic period, testosterone secreted by testicular mesenchymal cells in patients with AIS fails to stimulate the development of the Wufei duct to form the male internal genitalia due to abnormal androgen receptors. The testicular support cells secrete normal MIS and the Müllerian ducts are suppressed in the absence of the fallopian tubes, uterus, cervix and upper vagina. Upon reaching puberty, a small amount of estrogen can lead to breast development and a female physique due to the complete lack of androgen suppression. Studies have found that patients with AIS are 10 times more sensitive to estrogen than normal males.2. Incomplete androgen insensitivity: The range of clinical manifestations in these patients is extremely variable. The main difference with the complete type is that there are different degrees of male androgen insensitivity syndrome, incomplete typing, including enlarged clitoris and partial fusion of the labia, pubic and axillary hair development at puberty. 1947 Reifenstein reported an X-linked familial disease, mainly manifesting as perineal scrotal hypospadias, breast dysplasia and infertility, now In 1979, Aimen et al. reported that androgen receptor abnormalities were also found in patients with normal male phenotype with only primary infertility and azoospermia or oligospermia. [1] In normal men with hormonal alterations, the interstitial cells of the testis are stimulated by pituitary LH to secrete testosterone; testosterone in turn exerts a negative feedback regulation on LH secretion. There is an abundance of androgen receptors in the hypothalamus and pituitary gland. Prepubertal AIS patients usually have age-appropriate LH and testosterone levels, similarly in neonates and young children, but the LH and testosterone peaks seen in normal male infants at the sixth week of life are not seen in AIS patients. After puberty, testicular secretion of testosterone increases, and due to androgen receptor defects, resulting in insufficient negative feedback from testosterone to the hypothalamic-pituitary system, resulting in higher LH levels in AIS patients than in normal males; FSH secretion is the same as or increases in normal male levels. Increased LH has the effect of stimulating the testes to secrete more testosterone and estrogen, with estrogen coming mainly from the testes and to a lesser extent from the conversion of androstenedione and testosterone by aromatization in peripheral tissues. Due to the increased stimulation of mesenchymal cells by elevated LH, estrogen production is approximately twice as high as in normal males. Thus, testosterone and estrogen in AIS after puberty are at the normal high limit or elevated. after HCG stimulation, there is a normal increase in blood testosterone and DHT. Pathologic features of the testis The typical gross specimen of the testis and its accessory tissues in such patients has three components: (i) a testis often with multiple tan or white nodules; (ii) a white thread-like hard smooth muscle body fused to the midline of the testis; and (iii) accessory cysts of varying size adjacent to it. The testicular parenchyma microscopically had one of the following four changes: (1) diffuse tubular interstitium; (2) lobulated tubular interstitium; (3) mixed tubular interstitium; and (4) predominantly interstitial. In most testes, the interstitial cells are hyperplastic, the varicocele is markedly atrophied and rigid and filled with immature supporting cells, and most are not spermatogenic. muller reported that testicular pathology in patients with AIS younger than 5 years of age is identical to that of undescended testes with a normal number of germ cells; older than 7 years of age, germ cells are absent or seen in small numbers. [1]