The Huffington Post

The theory holds that the same genetic factors that induce gayness in males also promote fecundity (high reproductive success) in those males’ female maternal relatives. Through this trade-off, the maternal relatives’ “gay man genes,” though they aren’t expressed as such, tend to get passed to future generations in spite of their tendency to make their male inheritors gay.

—Why Are There Gay Men? Because Women Who Inherit ‘Gay Genes’ Have More Kids, Scientists Say