中间性 - 中间性性象谱

中间性的原因- 激素因素

5-α-还原酶缺乏(5-ARD)

生来就带有5-α-还原酶缺乏的孩子是具备XY染色体组型的遗传上的男性。但是，他们有隐睾症，而且其外部性器官可能看起来莫凌两可或无疑地为女性特征：他们的阴茎偏小(起初常常被误认为扩大的阴蒂)，而且有阴道和大、小阴唇，却无子宫和无输卵管。具有明白无误的女性性器官的那些孩子通常会作为女孩子来抚养，可是，他们中的许多人在青春期睾丸会下降，并且发育出男性第二性征。然后，他们会放弃女性性角色而采用男性性身份。
在此勿需深入了解任何生物学或医学细节，您也能够说出这种病症的致病原因：缺乏一种被称为5-α-还原酶的必需酶，并且由此而导致男胎的正常发育受到损害。他们甚至于在成年期，其前列腺仍然偏小，并有不育的可能。同理，他们的面部毛发较少(另一方面，他们也没有男性模式的秃头)。这种疾病是遗传来的，但非常罕见。只有在多米尼加共和国和其他一些国家才发现有群发病案，在那些与外界相对隔绝的国家里，他们中许多人相互通婚，(因而将疾病遗传给下一代)。

Intersexuality - The Intersexual Spectrum

Causes of Intersexuality - Hormones

5-Alpha-Reductase Deficiency (5-ARD)

Children born with 5-ARD are genetic males with an XY- chromosome combination. However, they have undescended testicles, and their external sex organs may look ambiguous or clearly female: They may have a small penis (at first often mistaken for a large clitoris), and a vagina and vaginal lips, but no uterus and no Fallopian tubes. Those children with apparently female sex organs will usually be raised as girls, but, in many cases, their testicles descend during puberty, and they develop male secondary sexual characteristics. They then abandon the female role and adopt a male identity.
Without going into any greater biological or medical detail here, one can say this about the cause of the condition: A certain essential enzyme called 5-alpha reductase is deficient, and thus the typical development of the male fetus is impaired. Even in adult males, the prostate remains small, and there is the likelihood of infertility. Also, there is very little facial hair (on the other hand, there is no male-pattern baldness, either). The condition is inherited, but very rare. Some clusters of it are found only in the Dominican Republic and a few other countries, where, in relatively isolated communities, many people are related to each other.