Autism Affects Boys 4 Times More Often Than Girls. Study Finds Clue to Why

Key Points:

• New research published in the American Journal of Human Genetics suggests that genetic differences on the X chromosome, inherited from healthy mothers, may contribute to why autism is diagnosed about four times more often in boys than girls.
• The study analyzed genetic data from over 8,000 families and identified 22 rare variants in regulatory regions of the MECP2 gene that could influence autism susceptibility in males, as males have only one X chromosome and thus less protection from harmful variants.
• Experts caution that autism is highly heterogeneous and that genetic findings do not fully explain the diagnostic disparity, noting that girls may be underdiagnosed due to less obvious symptoms and camouflaging behaviors.
• The research highlights potential genetic differences in autism between boys and girls and underscores the need for improved diagnostic approaches that consider these differences, which could lead to better identification of autism in females.
• While genetic susceptibility is important, differences in recognition, referral, and assessment processes also play a significant role in the historical underdiagnosis of autism in girls and women.