In particular, subject ID1 also presented with a de novo 276 kb microdeletion at Xp22.1, including DDX53. This gene has recently emerged as a significant ASD risk factor, being involved in synaptic function [25, 26]; however, an overlapping genetic basis among ASD and ADHD has been evidenced [27], therefore this gene could contribute to our patient’s neurodevelopmental disorder, even if it does not seem to be fully causative by itself, especially considering his dysmorphic features and CAS, which are more typical of SETBP1-HD. This evidence concerns the gene SETBP1 and attention deficit-hyperactivity disorder.