Angelman Syndrome

by Ciara Minion

Definition

Angelman Syndrome is a genetic disorder that causes developmental disabilities and neurological problems, such as difficulty speaking, balancing and walking and, in some cases, seizures. Frequent smiles and outbursts of laughter are common for people with Angelman Syndrome, and many have happy, excitable personalities.

Symptoms

  • Developmental delays, such as lack of crawling or babbling at 6 to 12 months, and intellectual disability
  • Lack of or minimal speech
  • Inability to walk, move or balance well
  • Trembling movement of arms and legs
  • Frequent smiling and laughter
  • Happy, excitable personality
  • Seizures, usually beginning between 2 and 3 years of age
  • Stiff or jerky movements
  • Small head size, with flatness in the back of the head
  • Crossing of the eyes
  • Tongue thrusting
  • Walking with arms up in the air
  • Light pigmentation in hair, skin and eyes

Causes

  • It's most often caused by problems with a gene located on chromosome 15 called the ubiquitin-protein ligase E3A (UBE3A) gene.
  • Normally, only the maternal copy of the UBE3A gene is active in the brain, caused by what's known as genomic imprinting. Most cases of Angelman syndrome occur when part of the maternal chromosome 15, which contains this gene, is missing or damaged. In a small number of cases, Angelman syndrome is caused when two paternal copies of the gene are inherited, instead of one paternal and one maternal copy.
  • It can be inherited.

Tests and diagnosis

Confirming a diagnosis of Angelman syndrome requires taking a blood sample from your child for genetic studies. A combination of genetic tests can reveal the chromosome defects related to Angelman syndrome. These tests look at:


  • Chromosome size, shape and number
  • Missing chromosomes
  • Parental DNA pattern
  • Gene mutation

Treatment


  • There is no cure, so doctors typically just try to limit the symptoms by prescribing:
  • Anti-seizure medication
  • Physical therapy
  • Communication therapy
  • Behavior therapy
Angelman Syndrome: Close to a cure?