Genetics and Orientation
Dr. Cynthia Chappell discusses the results of family and twins studies that point to the link between genes and sexual orientation.
Genes are involved in sexual orientation.
Pedigree studies are studies that look at families with two or more gay children and explore the incidence of homosexuality in maternal and paternal family histories. Birth order studies look at the incidence of homosexuality and birth order. Twin studies are studies that look at incidence of homosexuality in families where there are twins. Family studies have indicated that a genetic link is likely.
Molecular Studies (Chromosomal Areas)
Family studies pointed to a genetic component to sexual orientation. Molecular studies sought to find chromosomal areas in which genetic links occur.