Kikuchi Iwaho, Takeuchi Hiroyuki, Kinoshita Katsuyuki
Department of Obstetrics and Gynecology, Juntendo University School of Medicine.
Nihon Rinsho. 2004 Feb;62(2):309-12.
Sex determination and differentiation depend on differentiation of the indifferent gonad to the testis or ovary, which leads to masculine or feminine differentiation of internal and external genitalia. Recently, genes involved in this cascade have been identified with the advance of molecular genetical analysis. XY gonadal dysgenesis, this is a condition that has XY chromosome but is characterized by the indifferent testis. There are complete and incomplete types. Complete type has bilateral gonads of cordee, does not show physical characteristics of Turner's syndrome, has the uterus and ovaries, and has the vagina in female type, though the external genitalia are immature. Incomplete type is characterized by bilateral testicular hypoplasia(male pseudohermaphroditism) or unilateral testicular hypoplasia and bilateral restiform gonads(mixed gonadal dyspenesis), and the sexuality of the external genitalia is unclear. XX gonadal dysgenesis, complete type is characterized by bilateral restiform gonads, female type internal and external genitalia and sexual immaturity, though it does not show any characteristics of Turner's syndrome. It presents hypergonadotropic hypogonadism endocrinologically. It shows a familial incidence with autosomal recessive inheritance, and sensorineural deafness is accompanied in some cases. Incomplete type has rudimentary ovaries and show a varying degree of secondary sexual characteristics. Mixed dysgenesis, many cases have XO/XY mosaic and this dysgenesis is characterized by unilateral hypoplastic testis and contralateral restiform gonad. It may occur in cases of incomplete type XY gonadal dysgenesis. Trisomy X, cases of trisomy X have three X chromosomes as this term indicates. There are some cases of polisomy with four or more X chromosomes. The frequency of trisomy X has been reported to be one in 1,000 births of female, which means that it is a relatively common chromosomal aberration. It has been reported that about 20% of cases of trisomy X have sexual dysfunction, predominantly with primary amenorrha.
性别决定和分化取决于未分化性腺向睾丸或卵巢的分化，这会导致内外生殖器的男性化或女性化分化。最近，随着分子遗传学分析的进展，参与这一过程的基因已被确定。XY性腺发育不全，即一种具有XY染色体但以未分化睾丸为特征的病症。有完全型和不完全型。完全型有双侧条索状性腺，不表现特纳综合征的身体特征，有子宫和卵巢，外生殖器为女性型但未发育成熟。不完全型的特征是双侧睾丸发育不全（男性假两性畸形）或单侧睾丸发育不全和双侧条索状性腺（混合性腺发育不全），外生殖器的性别不明确。XX性腺发育不全，完全型的特征是双侧条索状性腺、女性型内外生殖器和性不成熟，尽管不表现任何特纳综合征的特征。其内分泌表现为高促性腺激素性性腺功能减退。它呈常染色体隐性遗传的家族性发病，有些病例伴有感音神经性耳聋。不完全型有发育不全的卵巢，并表现出不同程度的第二性征。混合性发育不全，许多病例为XO/XY嵌合体，这种发育不全的特征是单侧发育不全的睾丸和对侧条索状性腺。它可能发生在不完全型XY性腺发育不全的病例中。X三体综合征，顾名思义，X三体综合征的病例有三条X染色体。也有一些四条或更多X染色体的多体病例。据报道，X三体综合征的发生率为每1000例女性出生中有1例，这意味着它是一种相对常见的染色体畸变。据报道，约20%的X三体综合征病例存在性功能障碍，主要是原发性闭经。
