[6] Occasionally it is due to the inheritance of two copies of chromosome 15 from the father and none from the mother (paternal uniparental disomy).

This can be due to genetic errors such as the deletion or mutation of a segment of chromosome 15, uniparental disomy, or translocation.

[17] Specifically, the paternal copy of UBE3A is known to be imprinted within the hippocampus, cortex, thalamus, olfactory bulb, and cerebellum.

The third pattern, 3–6 Hz activity punctuated by spikes and sharp waves in occipital leads, is associated with eye closure.

Additionally, among a cohort of 163 individuals with AS, ranitidine was shown to be the most frequently prescribed medication for treating gastroesophageal reflux disease (GERD).

[citation needed] Occupational therapists can contribute to the development and augmentation of non-verbal communication skills by addressing the foundational skills such as finger isolation, motor planning, hand-eye coordination, spatial awareness, and refining gestures.

[32] Occupational therapists can work together with these individuals to improve their visual perceptual skills and increase their sensory awareness.

[33] People with AS tend to have much higher receptive language abilities than expressive; recent studies have shown that patients with AS have typical auditory brain region responses to speech but atypical memory responses, suggesting that word meaning recall is delayed or processed differently in AS.

[34] This may be caused by the altered cortical morphology seen in AS [35] in the precuneus, a region of the brain involved in self-reflection and memory.

It does not involve replacing or activating the UBE3A gene, instead it is a mechanism aimed at improving various symptoms of AS such as learning, sleep, and seizure control.

Further, the specific genetic mechanism underlying the condition is thought to correlate to the general prognosis of the affected person.

Also noteworthy are the reports that the frequency and severity of seizures temporarily escalate in pubescent Angelman syndrome girls, but do not seem to affect long-term health.

[citation needed] Dressing skills are variable and usually limited to items of clothing without buttons or zippers.

Most adults can eat with a knife or spoon and fork, and can learn to perform simple household tasks.

People with Angelman syndrome appear to have a reduced but near-normal life expectancy, dying on average 10 to 15 years earlier than the general population.

[45] Harry Angelman, a pediatrician working in Warrington, England, first reported three children with this condition in 1965.

They had a variety of disabilities and although at first sight they seemed to be suffering from different conditions I felt that there was a common cause for their illness.

The diagnosis was purely a clinical one because in spite of technical investigations which today are more refined I was unable to establish scientific proof that the three children all had the same handicap.

However, when on holiday in Italy I happened to see an oil painting in the Castelvecchio Museum in Verona called ... a Boy with a Puppet.

[50] Many poems in Richard Price's poetry collections Hand Held (1997), Lucky Day (2005), and Small World (2012) reflect on his daughter, who has Angelman syndrome.

In October 2007, actor Colin Farrell publicly announced that his son has Angelman syndrome.