Genetics and Orientation

Dr. Cynthia Chappell discusses the results of family and twins studies that point to the link between genes and sexual orientation.

Introduction

Genes are involved in sexual orientation.

Pedigree Studies

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.

SCIENCE OF SEXUAL ORIENTATION

Why are some people gay? This is often the first question one asks when discovering or being told that a family member is gay.  Parents may even think, “What did I do wrong?”

Continue to Section…

GENETICS AND ORIENTATION

Dr. Cynthia Chappell discusses the results of family and twins studies that point to the link between genes and sexual orientation.

Continue to Section…

NATURE VS. NURTURE

From as recent as the 1980s there was a belief that people were born with no sexual preference and that life experiences were the determining factors that led to a particular sexual orientation. 

Continue to Section…

PRENATAL DETERMINATION

Dr. Cynthia Chappell discusses prenatal hormones, hypothalamic activation, and dimorphic characteristics positing that sexual orientation is determined during the 8th through the 16th week of pregnancy.

Continue to Section…