Male sexual orientation and genetic evidence

Genetic and Environmental Influences on Sexual Orientation

The primary focus of this chapter is to provide an overview of the evidence to date on the quantitative genetics of sexual orientation, including family and twin studies. The bulk of the available evidence suggests moderate heritability for male sexual orientation. Female sexual orientation has been studied much less extensively, but current studies are consistent with a genetic contribution fo...

Genetic linkage and male homosexual orientation.

Genetic feminization of brain structures and changed sexual orientation in male Drosophila.

The neural basis of sexual orientation in Drosophila was studied by the production of males with regionally feminized brains. Such flies express the female form of the sex determination gene transformer in a limited number of neurons under the control of GAL4 enhancer trap inserts. This method facilitated the creation of lines with a stable pattern of feminization. In tests of sexual preference...

Sexual orientation, theory of mind and empathy: a comparison of male homosexual and male and female heterosexuals

Background: Researchers have been investigating similarities of and differences between homosexuals and heterosexuals for past few decades. Several studies have shown that in the particular domain (e.g., spatial ability), male homosexuals would resemble female heterosexuals better than male heterosexuals. Executive function, however, has received more attention than social cognition in this lin...

Male and female sexual orientation differences in gambling

The purpose of this study was to determine whether sexual orientation differences in gambling exist that parallel those for sex—a question motivated by the idea that male homosexuality arises from prenatal brain feminization and that female homosexuality arises from prenatal brain masculinization. For gambling frequency, we hypothesized that male homosexuals would be more similar to female hete...