Your Psychology and Mental health Portal
PsychNet-UK - Psychology and Mental health Forum
Mental Health and Psychology Portal
Angelman Syndrome


Angelman Syndrome is a rare neurological disorder disorder that is predominantly caused by deletions on chromosome 15 given by the mother and is characterized by severe congenital mental retardation, unusual facial appearance, and muscular abnormalities.

Angelman syndrome (AS) is characterized by:

Symptoms that are always present:

Severe developmental delay such as delay in sitting, crawling and walking or mental retardation.

Jerky, marionette-type movements, stiff-legged walking style and hand flapping.

Severe speech impairment.

Movement or balance disorder, gait ataxia and/or tremulousness of the limbs.

Hyperactive behavior.

A unique behavior with an inappropriate happy demeanor that includes frequent laughing, smiling, and excitability.

Symptoms that are sometime present:

Small head.

Characteristic EEG abnormalities.

Seizures, onset usually before 3 years of age.

The characteristic features of this condition are not always obvious at birth but evolve during childhood. Characteristic features of Angelman Syndrome that can be present include:

Flattened back of the head.
Deep-set eyes.
Wide, ever-smiling mouth.
Prominent jaw and widely spaced teeth.
Lightly pigmented hair, skin and eyes.

Although Angelman Syndrome is usually not recognized at birth or in infancy since the developmental problems are nonspecific during this time. Parents may first suspect the diagnosis after reading about Angelman Syndrome or meeting a child with the condition. The most common age of diagnosis is between three and seven years when the characteristic behaviors and features become most evident.

Associated Features:

Microcephaly and Seizures are common.
The child easily moved to laughter.
Loving, happy and social demeanour.
Feeding difficulties.
Disturbed sleep.
Delayed toilet training.
Flat occiput (back of the head).
Occipital groove.
Protruding tongue.
Tongue thrusting; suck/swallowing disorders.
Feeding problems during infancy.
Projecting jaw.
Wide mouth, wide-spaced teeth.
Frequent drooling .
Excessive chewing/mouthing behaviors.

Differential Diagnosis:

Some disorders have similar or even the same symptoms. The clinician, therefore, in his/her diagnostic attempt has to differentiate against the following disorders which need to be ruled out to establish a precise diagnosis.
Prader-Willi Syndrome.
Rett Syndrome - particularly in infant girls.
Cerebral Palsy.
Static Encephalopathy.
Idiopathic Epilepsy.

Angelman Syndrome is caused by; deletion of the AS/PWS region on the copy of chromosome 15 inherited from the mother.


There is no standard course of treatment for Angelman Syndrome. Physical therapy and adaptive devices may help patients with jerky gait. Early language evaluation and intervention is often recommended.

Counseling and Psychotherapy [ See Therapy Section ]:

Behavior Modification.
Speech Therapy.
Communication Therapy.

 Pharmacotherapy [ See Psychopharmacology Section ] :

Anticonvulsant medications may be prescribed for epilepsy. 

DSM Code



Disorder Sheets

Assert UK
PO Box Nuneaton
CV11 9FD

Recommended Book

Prader-Willi Syndrome: And Other Chromosome
15Q Deletion Disorders - Click Here to View

Angelman Syndrome

Misc Information


Child Psychology - Disorders