Clinical exome sequencing (CES) revealed the presence of a de novo variant c.3385C>T (p.Arg1129*) in KAT6A (ACMG class IV PVS1, PM2) in the patient with this complex phenotype, which led to the diagnosis of Arboleda-Tham syndrome (ARTHS; OMIM 616268). This evidence concerns the gene KAT6A and autosomal dominant intellectual disability-craniofacial anomalies-cardiac defects syndrome.