New Gene Linked to Autism: DDX53 and the X Chromosome
Dr. Stephen Scherer (left), Chief of Research at SickKids Hospital, and Dr. Marla Mendes, a research fellow, inside a lab at SickKids Hospital in Toronto, on Dec. 20. They identified 59 genetic variants on the X chromosome significantly associated with autism.EDUARDO LIMA/The Globe and Mail
Scientists have made a significant breakthrough in understanding the genetics of autism. For the first time, a gene called DDX53 has been directly linked to this complex developmental disorder. This discovery provides crucial information for researchers seeking to unravel the mysteries surrounding autism, a condition that affects millions worldwide.
The identification of DDX53 is particularly noteworthy because its location on the human X chromosome offers valuable insights into why autism is more prevalent in males (about four times more likely) than females.
DDX53: A Key Player in Neurodevelopment
“If you’re male and you don’t have a copy of this gene, you’re going to be on the spectrum,” said Dr. Stephen Scherer, chief of research at Toronto’s Hospital for Sick Children (SickKids), which played a key role in the discovery.
This finding is based on two studies published in the American Journal of Human Genetics. The first study, led by researchers at SickKids, focused on individuals with ASD and identified a connection between DDX53 and the disorder.
The second study independently examined variations across the entire X chromosome in individuals with ASD, further supporting the role of DDX53 and identifying 17 other potential genes involved.
Understanding the X Chromosome and Autism
Males possess only one X chromosome, while females have two. This means a defective gene on the X chromosome in males will result in the condition, while females may have a functioning copy on their second X chromosome that can compensate. This explains the higher prevalence of autism in males.
DDX53 plays a crucial role in RNA helicases, proteins found in the cell nucleus responsible for regulating gene expression. These proteins are involved in turning genes on or off during development. Faulty DDX53 can disrupt this intricate process, potentially contributing to neurodevelopmental challenges associated with autism.
Implications for Diagnosis and Treatment
These findings offer hope for families seeking answers about autism. Knowing which genes are involved can help personalize diagnoses and identify potential therapeutic targets.
“I find that for my patients, having a specific diagnosis helps them find their own community, so they become experts of their own gene,” said Dr. Myriam Srour, a pediatric neurologist at the Montreal Children’s Hospital who was not involved in the studies.
The research underscores the complexity of autism, highlighting the need for continued research and understanding.
Interested in learning more about autism genetics and research? Visit the Autism Speaks website.