What It Is

Angelman Syndrome is a genetic disorder that causes developmental delay and neurological problems.  Angelman Syndrome is due in most cases to a chromosome deficiency involving loss of material from chromosome region 15q12. The deficient chromosome is passed on from the mother.

Deletion of chromosome region 15q12 causes both Angelman Syndrome and a totally different disorder called Prader-Willi Syndrome.  While the deleted chromosome is of maternal origin in Angelman Syndrome, it is the paternal chromosome that is partially deleted in the Prader-Willi Syndrome. 

There are rare families with more than one child with Angelman Syndrome. 


According to the National Institute of Neurological Disorders and Stroke:

Infants with Angelman Syndrome appear normal at birth, but often have feeding problems in the first months of life and exhibit noticeable developmental delays by 6 to 12 months. Seizures often begin between 2 and 3 years of age. Speech impairment is pronounced, with little to no use of words. Individuals with this syndrome often display hyperactivity, small head size, sleep disorders, and movement and balance disorders that can cause severe functional deficits.

Treatments & Therapies

There is no known treatment or cure for Angelman Syndrome.  

Many children with Angelman Syndrome take medicine to control seizures.  Different forms of therapy like physical, speech, behavioral, etc can be helpful for a child to reach their maximum development potential.

  • The description of this disease is provided courtesy of the NIH, and other sources.
  • The information provided on this web site should NOT be used as a substitute for seeking professional medical diagnosis, treatment or care. You should not rely on any information in these pages to replace consultations with qualified health professionals.