Hormones and psychosexual differentiation.
The male phenotype arises from the optimal concordance of chromosomal, gonadal and hormonal sex. Hormonal sex depends directly on the type of gonads that have been formed, and is linked both to the production of hormones and to their optimal effect on target tissues. The present review underlines the fact that psychosexual orientation in the male is also related to factors linked to sex hormones. Many of the experimental and clinical data available militate against the long-held belief that the development of role and gender identity in man is predominantly determined by environmental factors. This study points out the importance of hormonal factors at the CNS level. The most common abnormalities of sexual orientation are homosexuality and transsexualism. Despite their relatively high frequency in the general population, research into possible biological influences in these abnormalities is very scant. The authors of the present paper have reviewed the literature data yielded by biological and hormonal studies on homosexuality and transsexualism. These data seem to support the hypothesis that androgens may be deficient in the CNS of male homosexuals. Morphological or functional (neurotransmitter) anomalies in androgen actions at the CNS level could also favor radical dissociation between psychological sex and gonadal, hormonal and phenotypic sex in transsexualism. In conclusion, the present review seems to indicate that hormonal factors (gonadal and adrenal hormones, hormone receptors, transduction mechanism of the hormonal signal, neurosteroids, neurotransmitters etc.) play a determining role in the formation of gender identity.
Giordano
G
G
DISEM, Cattedra di Endocrinologia, Genova.
Giusti
M
M
D000328:Adult; D000818:Animals; D002369:Castration; D002490:Central Nervous System / Q000033:anatomy & histology / Q000196:embryology / Q000502:physiology; D002648:Child; D005260:Female; D005783:Gender Identity; D018507:Gene Expression Regulation, Developmental; D006065:Gonadotropins, Pituitary / Q000502:physiology; D006066:Gonads / Q000196:embryology / Q000378:metabolism; D006716:Homosexuality; D006728:Hormones / Q000009:adverse effects / Q000494:pharmacology / Q000502:physiology* / Q000627:therapeutic use; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology; D008297:Male; D011606:Psychosexual Development / Q000502:physiology*; D012727:Sex Characteristics; D012732:Sex Determination Analysis; D012725:Sexual Behavior / Q000502:physiology; D013045:Species Specificity; D014189:Transsexualism / Q000188:drug therapy / Q000503:physiopathology / Q000601:surgery
D006065:Gonadotropins, Pituitary; D006728:Hormones