Angelman Syndrome

Angelman syndrome may be suspected if a child's development is delayed and they have the syndrome's distinctive characteristics (see above).

A blood sample can be takento confirm the diagnosis. Anumber of genetic tests will be carried out on the sample. These may include:

• chromosome analysis to see if any parts of the chromosomes are missing(deletions)
• fluorescence in situ hybridisation (FISH) used to check specifically for chromosome 15 deletions when Angelman syndrome is suspected, or to check the mother's chromosomes
• DNA methylation which shows whether the genetic material on both the mother's and father's chromosomes is active
• UBE3A gene mutation analysis used to see if the genetic code on the maternal copy of the UBE3A gene is altered

For each child with Angelman syndrome, it's important to know the genetic change that caused the condition. This helps todetermine whether there'sa riskof itoccurring again in another child, or whether there are implications for other members of the family.

Most children with Angelman syndrome are diagnosed between the ages of 18 months and 6years, when the typical physical and behavioural symptoms become apparent.

If your child is diagnosedwith Angelman syndrome, you should be given the opportunity to discuss the genetic diagnosis and implications with a genetic doctor.