In this review, we have attempted to summarize the structure and function of the UBE3A gene and its protein product; UBE3A’s mechanistic role in the various autism spectrum disorders (ASDs); the role of the 15q11–q13 region and the various genetic perturbations occurring within this chromosome 15 locus causing the ASDs; the potential usage of UBE3A in ASD biomarker studies; and the existing therapeutic interventions against UBE3A-mediated neurodevelopmental disorders. This evidence concerns the gene UBE3A and neurodevelopmental disorder.