An autosomal recessive disorder characterized by global developmental delay with severely impaired intellectual development, impaired motor development, axial and peripheral hypotonia, poor speech and significant behavioral abnormalities, including autism spectrum disorder, hyperactivity, mood disorders, aggression, hand and face stereotypies, sleep disturbances, anxiety, self-injurious behavior, and bruxism. The disease is neurodevelopmental disorder with behavioral abnormalities, absent speech, and hypotonia (EFO_0010658, an Experimental Factor Ontology term).