SETBP1 and apraxia: Moreover, in independent exome sequencing of clinically-defined speech disorders, we identified an unrelated Australian case of CAS, together with oral apraxia, dysarthria, moderate ID, seizures and motor impairments, with a de novo LoF mutation disrupting SETBP1. This child carried a novel premature stop variant (c.C2665T, p.R889X) in SETBP1 that was not present in her unaffected parents.