Grant: Project Grant

Autism spectrum disorders (ASD) are a group of lifelong neurodevelopmental conditions that affect the way a person communicates with and relates to other people and the world around them. Neuroimaging studies have shown that atypical brain development in ASD leads to differences in the way brain areas are connected and how they function together. Our knowledge of how these differences in brain structure and function relate to behaviour is limited by the significant heterogeneity among subjects diagnosed with ASD. Studying individuals with a shared genetic risk factor for ASD allows us to reduce group heterogeneity and focus on common mechanisms that lead to cognitive impairment and autistic behaviours. 16-34% of individuals with a genomic copy number variation (CNV) at the 16p11.2 locus are diagnosed with autism or have autistic behaviours. Magnetic resonance imaging (MRI) studies of these individuals have reported differences in the microstructure of the brain's white matter in comparison to neurotypical subjects, which suggests that myelin, a cellular membrane wrapped around axons to enable efficient and synchronized communication between brain areas, is affected. We hypothesize that individuals with 16p11.2 CNVs have atypical brain myelination patterns that are related to the altered brain function and autistic behaviours in these individuals. This project builds on two neuroimaging-genetics research initiatives: CHUV Lausanne and Quebec 1000 Families. We will use state-of-the-art quantitative and high-resolution MRI techniques to acquire the most comprehensive multi-modal map of brain structure, myelination, and function of these individuals to date. This project is crucial to improve our understanding of these complex disorders and inform the development of effective therapies, including pro-myelinating therapies that have shown promising results in animal models.