The "gay uncle hypothesis" posits that people who themselves do not have children may nonetheless increase the prevalence of their family's genes in future generations by providing resources e. The most recent literature from the APA says that sexual orientation is not a choice that can be changed at will, and that sexual orientation is most likely the result of a complex interaction of environmental, cognitive and biological factors Diamond disagrees that researchers need to find a mechanism to explain the persistence of genetic variants linked to homosexuality. A cell-killing strategy to slow aging passed its first test this year. There is no indication that social environment after birth has an effect on gender identity or sexual orientation. Want more award-winning journalism?
Findings from such large studies are more likely to be replicated than the small studies in the past, Bailey says.
Genes linked to being gay may help straight people get more sex
InDick Swaab and Michel A. Retrieved June 12, Principles and Practice of Psychiatric Nursing. The first group comprised 19 gay men who had died of AIDS -related illnesses. Kallmann FJ April Evolution and Human Behavior. Controversial experiments that could make bird flu more risky poised to resume By Jocelyn Kaiser Feb.
A study of all adult twins in Sweden more than 7, twins  found that same-sex behavior was explained by both heritable factors and individual-specific environmental sources such as prenatal environment, experience with illness and trauma, as well as peer groups, and sexual experienceswhile influences of shared-environment variables such as familial environment and social attitudes had a weaker, but significant effect. Equal protection analysis in U. The second group comprised 16 men whose sexual orientation was unknown, but whom the researchers presumed to be heterosexual. One possible explanation for why it is, they say, is that the same genetic factors also give a reproductive advantage to straight people who have them. The research points to childhood separation anxiety as a culturally universal correlate of androphilia in men. They described their intent to perform a genome-wide association study, a technique originally developed to locate genetic susceptibilities to diseases like macular degeneration and diabetes.