Gay brains structured like those of the opposite sex
Brain scans have provided the most compelling evidence yet that being gay or straight is a biologically fixed trait.
The scans reveal that in gay people, key structures of the brain governing emotion, mood, anxiety and aggressiveness resemble those in straight people of the opposite sex.
The differences are likely to have been forged in the womb or in early infancy, says Ivanka Savic, who conducted the study at the Karolinska Institute in Stockholm, Sweden.
"This is the most robust measure so far of cerebral differences between homosexual and heterosexual subjects," she says.