Head of Human Genome Project: "Homosexuality Is Not Hardwired"

Francis S. Collins, one of the world's leading scientists who works at the cutting edge of DNA research, concluded that "there is an inescapable component of heritability to many human behavioral traits." However, he adds, "for virtually none of them, is heredity ever close to predictive."
. . .
The heritability estimates for personality traits were varied: General Cognitive Ability (50%), Extroversion (54%), Agreeableness (42%), Conscientiousness (49%), Neuroticism (48%), Openness (57%), Aggression (38%) and Traditionalism (54%).
. . .
Dr. Collins succinctly reviewed the research on homosexuality and offers the following:

"An area of particularly strong public interest is the genetic basis of homosexuality. Evidence from twin studies does in fact support the conclusion that heritable factors play a role in male homosexuality. However, the likelihood that the identical twin of a homosexual male will also be gay is about 20% (compared with 2-4 percent of males in the general population), indicating that sexual orientation is genetically influenced but not hardwired by DNA, and that whatever genes are involved represent predispositions, not predeterminations [emphasis in original]."

The heritability estimates for homosexuality is substantially lower than General Cognitive Ability, Extroversion, Agreeableness, Conscientiousness, Neuroticism, Openness, Aggression and Traditionalism!

at NARTH here.