Researchers are a step closer to understanding why autism spectrum disorder affects four times as many boys as girls.
A study led by a team of Toronto scientists has discovered that males who carry specific genetic alterations on their X-chromosome have an elevated risk for developing autism spectrum disorder, or ASD.
“The male gender bias in autism has intrigued us for years and now we have an indicator that starts to explain why this may be,” said co-principal investigator Stephen Scherer, director of the Centre for Applied Genomics at the Hospital for Sick Children.
Boys inherit one X-chromosome from their mother and one Y-chromosome from their father, explained Scherer. “If a boy’s X-chromosome is missing the PTCHD1 gene or other nearby DNA sequences, they will be at high risk of developing ASD or intellectual disability.
“Girls are different in that, even if they are missing one PTCHD1 gene, by nature they always carry a second X-chromosome, shielding them from ASD. While these women are protected, autism could appear in future generations of boys in their families.”
Autism spectrum disorder affects an estimated one in every 165 children, and often includes problems communicating and interacting with others, unusual patterns of behaviour and intellectual disability.
- Photos: Women's March In New York City30 Pictures
- PHOTOS: 16 Betty White quotes to brighten your day17 Pictures