Autism Spectrum Disorder comorbid with mild to severe ID is a consistent feature in all patients. Other frequent findings include hypotonia, motor delay, speech impairment, feeding problems in infancy, visual problems, and congenital heart defects. A seizure disorder was noted in two patients. Additional neuropsychiatric features are relatively common, including attention deficit/hyperactivity disorder, anxiety disorder and obsessive compulsive behavior. Dysmorphic features include a prominent forehead, high anterior hairline, ptosis, up-or down-slanted palpebral fissures, wide nasal bridge and a thin vermillion of the upper lip. Many affected individuals have ear abnormalities, including small low-set ears, and protruding cup-shaped ears.