COL4A2 and central nervous system disorder: This gene has been associated with a number of human central nervous system disorders, including ASD, intellectual disability, and spinal muscular atrophy.29 This patient also carries a heterozygous point mutation inherited from his mother in the COL4A2 gene (c.2921G>A; p.Gly974Glu; identified by gene-panel testing by clinical geneticists at the Hospital for Sick Children; and confirmed for this study with exome and Sanger sequencing).