What are the symptoms of angelman syndrome?

Early on: Seizures & microcephaly ( small head), developmental delays may present first, characteristic facial features ( e.g., pointed chin) are seen. Later, ataxic ( unsteady) gait hand -flapping, happy demeanor with frequent laughter, intellectual disability, hyperactivity, short attention span, severe language impairment, feeding problems, chewing/mouthing objects, gene involved is on chromosome 15.