Autism Symptoms in Children and Young Adults With Fragile X Syndrome, Angelman Syndrome, Tuberous Sclerosis Complex, and Neurofibromatosis Type 1: A Cross-Syndrome Comparison.

Objective: The etiology of autism spectrum disorder (ASD) remains unclear, due to genetic heterogeneity and heterogeneity in symptoms across individuals. This study compares ASD symptomatology between monogenetic syndromes with a high ASD prevalence, in order to reveal syndrome specific vulnerabilities and to clarify how genetic variations affect ASD symptom presentation.

Methods: We assessed ASD symptom severity in children and young adults (aged 0-28 years) with Fragile X Syndrome (FXS, = 60), Angelman Syndrome (AS, = 91), Neurofibromatosis Type 1 (NF1, = 279) and Tuberous Sclerosis Complex (TSC, = 110), using the Autism Diagnostic Observation Schedule and Social Responsiveness Scale.