Angelman Syndrome

Angelman syndrome is a genetic condition. It causes developmental delays, speech and balance issues, intellectual disability, and, in rare cases, seizures.

Angelman syndrome patients frequently smile and laugh, and they have happy, excitable personalities.

Seizures can start between the ages of two and three.

Angelman syndrome symptoms

The signs and symptoms of Angelman syndrome include:

  • Developmental delays, including decreased crawling or babbling between 6 and 12 months
  • Intellectual disability
  • Absent or infrequent speech
  • Difficulty walking and talking
  • Difficulty falling and staying asleep
  • Protruding tongue
  • Thinning of hair, skin and eyes
  • Unusual behavior such as clapping and raising arms when walking
  • Trouble sleeping
  • scoliosis


Angelman syndrome is a genetic disorder. It is usually caused by a problem with a gene on chromosome 15 called Ubiquitin-ligase E3A protein (UBE3A).

Missing or defective gene

You get a pair of genes from your parents: one from your mother (mother) and one from your father (father).

Your cells normally use information from these two copies, but in some genes, only one copy is active.

Normally, only the maternal copy of the UBE3A gene is active in the brain. Most cases of Angelman syndrome occur when parts of the mother’s copy are missing or damaged.

In a small number of cases, Angelman syndrome is caused by the inheritance of two paternal copies of the gene instead of one copy from each parent.

 Risk factors

Angelman syndrome is rare. Scientists often don’t know what causes the genetic changes that cause Angelman syndrome. Most people with Angelman syndrome symptoms have no family history.

Angelman syndrome can sometimes be inherited from either parent. A family history of this disease increases a child’s risk of Angelman syndrome.


Complications associated with Angelman syndrome include:

Difficulty feeding: Difficulty coordinating sucking and swallowing can lead to feeding problems in babies. Your pediatrician may recommend a high-calorie formula to help your child gain weight.

ADHD: Children with Angelman syndrome often move quickly from one activity to another, have a short attention span, and put their hands or toys in their mouths. ADHD usually decreases with age and usually does not require medication.

Sleep disturbances. People with Angelman syndrome often have abnormal sleep-wake patterns and may need less sleep than most people. Difficulty sleeping can improve with age. Medications and behavioral therapy can help control sleep disorders.

Curve of the spine (scoliosis): Over time, some people with Angelman syndrome develop abnormal curvatures of the left and right spine.

obesity. Older children with Angelman syndrome tend to have a large appetite, which can lead to obesity.


In rare cases, Angelman syndrome can be passed from an affected parent to a child through a defective gene. If you are concerned about a family history of Angelman syndrome or have already had a child with the disorder, consider talking to your pediatric neurologist or a genetic counselor to help you plan for a future pregnancy.

When to see a doctor?

Make an appointment with your child’s pediatric neurologist if your child seems to be experiencing developmental delay or other signs or Angelman syndrome symptoms.


A majority of children with Angelman Syndrome will have developmental and learning difficulties, motor difficulties and developmental delays. Though there is no specific treatment for this condition, early diagnosis and individualized treatment can improve their quality of lives.