De novo truncating mutations in Additional sex combs-like 3 (ASXL3) have emerged as the cause of BRS, while missense mutations in ASXL3 have been identified in individuals with autism spectrum disorder (ASD) (Dinwiddie et al., 2013; Russell and Graham, 2013; De Rubeis et al., 2014). Here, ASXL3 is linked to autism spectrum disorder.