KDM6A and Postnatal growth retardation: KDM6A pathogenic variants have been associated with the Kabuki syndrome (KS, MIM #300867), a congenital disorder characterized by DD/ID, typical facial features (i.e., ptosis and strabismus), minor skeletal anomalies, congenital heart defects, genitourinary anomalies, postnatal growth deficiency, and, rarely, polymicrogyria [49].