In the past few years, studies have linked various chromosomal regions, candidate genes and copy number variations to a higher risk of autism. But none of those findings explain why the condition is four times more common in boys than in girls.That question has been the focus of psychologist Simon Baron-Cohen and his colleagues at Cambridge University.Based on dozens of studies exploring sex differences in autism-related behaviors, Baron-Cohen has proposed a ‘fetal androgen theoryʼ: behaviors seen in autism are an exaggeration of normal differences between males and females, probably caused by exposure to high levels of male sex hormones in the womb.Read more at...SFARI, January 2009.