Oshima Hiroyuki
Tokyo Medical and Dental University, Tateyama Hospital.
Nihon Rinsho. 2004 Feb;62(2):293-9.
Sexual differentiation and development is a process from the moment of fertilization of a ovum by a spermatozoon to achievement of reproductive ability as a male or female. The process includes three steps; establishment of sex chromosome composition, gonadal differentiation and development, and acquirement of phenotypic expression by gonadal hormones. Therefore, abnormal sexual development is divided into three categories according to the above three steps. In humans, however, gender is assigned at birth. Then, individuals grow under social environment provided according to the gender assigned and acquire gender role during childhood and gender identity during puberty. As observed in those with trans-sexualism, it appears likely that gender identity plays a major role on sexual behavior of humans.
性分化与发育是一个从精子使卵子受精的那一刻开始，直至获得作为男性或女性的生殖能力的过程。该过程包括三个步骤：性染色体组成的确立、性腺的分化与发育，以及性腺激素诱导的表型表达的获得。因此，异常性发育根据上述三个步骤分为三类。然而，在人类中，性别在出生时就已确定。然后，个体在根据所确定的性别提供的社会环境中成长，并在童年时期获得性别角色，在青春期获得性别认同。正如在变性者中所观察到的那样，性别认同似乎在人类的性行为中起着主要作用。
