"Sexy" Smells Different for Gay, Straight Men, Study Says

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The findings suggest that brain activity and sexual orientation are linked. It also supports an opinion held by most scientists, that people are born—not bred—gay.
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The researchers found that the testosterone compound activated the hypothalamus in homosexual men and heterosexual women, but not heterosexual men. Conversely, the estrogen compound activated the hypothalamus only in heterosexual men.
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However, the new studies boost the hypothesis that homosexuality has a genetic basis and is not simply the result of learned behavior.
"This, incidentally, is not in any way controversial for biologists," Hamer said. "It's completely expected from the basic tenets of biology. It's only controversial because of the social and political controversy over homosexuality."