Gender - Biological Factors and Views

Biological Factors and Views

See also: Sexual differentiation and Sex determination and differentiation (human)

The biology of gender became the subject of an expanding number of studies over the course of the late 20th century. One of the earliest areas of interest was what is now called gender identity disorder (GID). Studies in this, and related areas, inform the following summary of the subject by John Money, a pioneer and controversial sex and gender researcher. He stated:

The term "gender role" appeared in print first in 1955. The term "gender identity" was used in a press release, November 21, 1966, to announce the new clinic for transsexuals at The Johns Hopkins Hospital. It was disseminated in the media worldwide, and soon entered the vernacular. The definitions of gender and gender identity vary on a doctrinal basis. In popularized and scientifically debased usage, sex is what you are biologically; gender is what you become socially; gender identity is your own sense or conviction of maleness or femaleness; and gender role is the cultural stereotype of what is masculine and feminine. Causality with respect to gender identity disorder is subdivisible into genetic, prenatal hormonal, postnatal social, and postpubertal hormonal determinants, but there is, as yet, no comprehensive and detailed theory of causality. Gender coding in the brain is bipolar. In gender identity disorder, there is discordancy between the natal sex of one's external genitalia and the brain coding of one's gender as masculine or feminine.

Money refers to attempts to distinguish a difference between biological sex and social gender as "scientifically debased", because of our increased knowledge of a continuum of dimorphic features (Money's word is "dipolar") that link biological and behavioral differences. These extend from the exclusively biological "genetic" and "prenatal hormonal" differences between men and women, to "postnatal" features, some of which are social, but others have been shown to result from "postpubertal hormonal" effects.

Although causation from the biological—genetic and hormonal—to the behavioural has been broadly demonstrated and accepted, Money is careful to also note that understanding of the causal chains from biology to behaviour in sex and gender issues is very far from complete. For example, the existence of a "gay gene" has not been proven, but such a gene remains an acknowledged possibility.

There are studies concerning women who have a diagnosis called congenital adrenal hyperplasia, which leads to the overproduction of masculinizing sex hormones, androgens. These women usually have normal female appearances (though nearly all girls with CAH have corrective surgery performed on their genitals) but despite of hormone-balancing medication that they are given since birth, they are statistically more likely to be interested in activities traditionally linked to males than females. Psychology professor and CAH researcher Dr. Sheri Berenbaum attributes these differences to exposure to higher levels of male sex hormones in utero.