SOC 152A Lecture Notes - Lecture 23: Twin Study, Twin, Fetus
Document Summary
Evidence for a biological influence on sexual orientation: homosexuality runs in families (pillard, if you"re male and you have a gay brother, then it increases your chances of being gay by 4-5 fold. Don"t know how it influences sexual orientation : epigenetic-dna tags differ between gay and straight twins at 2q37 and 16p13 consistent changes in two locations-don"t know what genes are involved here though chromosome 2 and 16. Prenatal sexual differentiation of brain gendered traits incl. sexual orientation. Homosexuality is linked to a spectrum of gender-atypical traits, especially in childhood higher level of testosterone in female fetuses that turn out to be lesbian individuals than female fetuses that show a lower level of testosterone. It"s not like you can predict the sexual orientation of children based on behavior but it"s a powerful tool for evaluation. Gay men performed better than heterosexual women, lesbians performed less than heterosexual men. Animal models of homosexuality can be generated by prenatal hormonal manipulation.
