While the scientists can't say what this means for sexual orientation in humans, it does raise the possibility that sexual preference is wired in an organism's brain.
Biologist Erik Jorgensen and his research team at the University of Utah took female nematodes with normal reproductive organs and activated genes that determine "maleness," thereby converting female brains to male brains.
"So we did that and now the females are attracted to other females," Jorgensen said from Salt Lake City. "That told us that the brain was sufficient for all of the sex-specific behaviours, for sexual attraction."
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