Some scientists say the political and moral debate over same-sex marriage frequently strayed from established scientific evidence, including comments by Republican vice-presidential candidate Sarah Palin that homosexuality is "a choice" and "a decision". Reuse this content. Most popular. It's not, since you had a one-night stand with your male friend, that you can choose to become straight. Evidence of that, said Michael Bailey, a professor of psychology at Northwestern University in Illinois, comes from studies of genetically male infants born with malformed or ambiguous genitals. Sven Bocklandt, a geneticist at the David Geffen school of medicine at UCLA, is bewildered by the argument that people choose their sexual attraction.
What scientists call "the fraternal birth order effect", the fact that each successive boy born to the same mother has a greater chance of being gay, may be due to an increasing immunological response by a mother's body to each male foetus in her womb.
One explanation is that women's sexual behaviour is driven more by relationships. Most popular. UntilCNN polls had found that a majority of Americans believed gay people could change their sexual orientation if they chose to; it was only last year that a majority for the first time said homosexuality was an inborn trait. Genetics Biology news.
Researchers are eagerly awaiting a DNA study of male siblings with at least one gay brother by Bailey and other scientists at Northwestern University due in earlybecause it may shed light on the role genetics plays in sexual attraction.