Myelin Alterations in Fragile X Syndrome : Insights into the Leading Inherited Form of Autism

Abstract

Shaima Hourani was a finalist in the 2026 UBC Three Minute Thesis (3MT) Competition. Shaima presented the research titled “Myelin Alterations in Fragile X Syndrome: Insights into the Leading Inherited Form of Autism.” Fragile X syndrome (FXS) is the most common inherited cause of autism spectrum disorder and intellectual disability. While most research has focused on neurons, emerging evidence supports the involvement of other cell types in the disorder. In particular, white matter alterations have been observed in individuals with FXS. White matter is enriched in myelin, a specialized structure in the nervous system that wraps around nerve fibres. In the brain, myelin is produced by specialized cells called oligodendrocytes. Proper myelination by oligodendrocytes is critical for normal brain function. How oligodendrocyte development and function are altered in FXS remains poorly understood. Using human stem cell–derived oligodendrocytes and mouse models of FXS, this research found delayed oligodendrocyte development and maturation, along with disrupted myelin structure. Understanding the mechanisms underlying white matter abnormalities and oligodendrocyte dysfunction in FXS may help identify new therapeutic targets and provide insight into other neurodevelopmental disorders. Shaima Hourani is completing a PhD in Medical Genetics in the Department of Medical Genetics under the supervision of Dr. Mahmoud Pouladi. #3MT is an academic competition that assists current graduate students with fostering effective presentation and communication skills. Participants have just three minutes to explain the breadth and significance of their research project to a non-specialist audience. For more information or to participate in UBC’s Three Minute Thesis (3MT) visit https://3mt.grad.ubc.ca.