Sex Differences in ASD Same as in General Population

Numerous studies have noted the differences in how autism spectrum disorder (ASD) manifests in boys and girls. A new study form the University of Miami (UM) finds that the differences between boys and girls with ASD are the same as the differences between boys and girls without ASD. Behaviors that are relevant to ASD are more frequently observed in boys, even when the boys are not at risk for ASD. The findings may explain why so many more boys are diagnosed with ASD than girls.

For the study, the researchers observed boys and girls beginning at 18 months of age. The sample included boys and girls with a high risk for ASD and boys and girls with a low risk for ASD. By the age of three years, one in four high-risk boys was identified with ASD, compared to only 1 in 10 of the high-risk girls.

The boys with ASD had higher levels of stereotyped behaviors, a symptom of autism. The boys with ASD also demonstrated less advanced cognitive and linguistic function than the girls with ASD. Interestingly, the researchers observed the same pattern in the boys and girls without ASD. Boys without ASD had more stereotyped behaviors and less advanced cognitive and linguistic function than girls without ASD. These findings suggest that the differences between boys and girls with ASD are part of a pattern of sex differences between boys and girls in the general population.

“The results imply that there may be an overrepresentation of boys with autism, based on sex differences that affect all children. In other words, the differences between boys and girls with autism are not specific to autism or even risk for autism,” stated the study’s principal investigator Daniel S. Messinger, professor of psychology at UM.

This research is published in the journal Molecular Autism.

Previous news in autism:

• Girls with ASD have different symptoms, diagnosed later