Angelman Syndrome

What is Angelman syndrome?

Angelman syndrome is a genetic disorder that causes mental and physical disability. Characteristic for the disease are above all the speech development disorder and excessive cheerfulness of the affected persons. Angelman syndrome occurs in boys and girls and affects about 1-9 per 100,000 births worldwide. It has similarities to Prader-Willi syndrome.


The cause of Angelman syndrome is a congenital genetic defect. It is caused by a so-called maternal deletion on chromosome 15, which means that a piece is missing on chromosome 15 inherited from the mother. This deletion is usually not inherited but arises spontaneously (new mutation).


The diagnosis of Angelman syndrome is often not made until the third to seventh year of life. The symptoms are often misinterpreted as a form of autism. Particularly conspicuous features of speech development, physical development and the characteristic appearance of the affected person suggest the suspicion of Angelman Syndrome. A definite diagnosis can only be made by a genetic test in which the deletion on chromosome 15 can be detected.

I recognize Angelman syndrome from these symptoms

In Angelman syndrome, delayed development of both motor and mental skills is already noticeable in infancy. Those affected suffer from a reduction in intelligence. Especially the speech development remains on a very low level.

However, speech comprehension is not impaired. People with Angelman syndrome suffer from hyperactivity, restlessness and an increased urge to move. The reflexes are also increased.

Typical are an insecure, choppy gait pattern and balance disorders. The majority of Angelman Syndrome patients suffer from pronounced forms of epilepsy. A curvature of the spine (scoliosis) also occurs frequently.

Also characteristic is a pronounced cheerfulness with frequent unfounded laughter. Those affected laugh more often when they are excited. In terms of appearance, a small head, a flat back of the head, a large mouth, a protruding chin, and strabismus are noticeable. The skin of people with Angelman syndrome is often very light.


The Angelman syndrome is not curable and there is no specific therapy. The therapy is therefore purely symptom-oriented. With the help of speech therapy, affected persons can learn sign language to enable better communication with their environment. Furthermore, physiotherapy and occupational therapy are recommended to promote motor development. If an epilepsy exists, a drug-based antiepileptic therapy should be initiated.

Duration / Forecast

No cure is possible for Angelman syndrome. A limited life expectancy does not exist either. However, complete autonomy, i.e. the ability to lead an independent life, is never achieved in people with Angelman syndrome. They need lifelong support to master everyday life.