Project 458617

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social communication difficulties and restricted/repetitive behaviours and interests. There has been substantial difficulty in understanding how the biological mechanisms of ASD influence one another at different levels of organization, as well as their effects on behaviour, cognition, and clinical presentation. A key obstacle may be the reliance on study designs that seek to identify differences between individuals diagnosed with ASD and typically developing controls. This approach is based on the assumption that any biological signatures found in ASD do not exist in the general population. However, such a view has received limited empirical support. Therefore, the present study aims to explore the presence of genetic susceptibility to ASD in a normative sample of subjects, then link these risk factors to brain structure and behaviour. To do so, a large and diverse pool of 11,878 participants aged 9 and 10 years old will be used. Polygenic risk scores, which represent genetic risk for ASD, will be examined in relation to various dimensions of brain structure as well as characteristics such as sex, gender, age, and performance on various cognitive and social functioning assessments. The findings of this study would ultimately help us understand whether certain features of ASD can be thought of as traits along a spectrum of normal variation. This would have critical implications on theoretical perspectives of ASD and would help guide future diagnostic and treatment efforts.