Characteristics of Angelman syndrome

The typical characteristics of Angelman syndrome aren't usually apparent at birth.

A child withAngelman syndrome will begin to show signs of delayed development at around 6-12 months, such as being unable tosit unsupported or make babbling noises.

Later, they may not speak at all or may only be able to say a few words. However, most children with Angelman syndrome will be able to communicate using gestures, signs or other systems.

The movement of a child with Angelman syndrome will also be affected. They may have difficulty walking because of problems with balance and co-ordination ( ataxia ). Their arms may tremble or move jerkily, and their legs may be stiffer than normal.

A number of distinctive behaviours areassociated with Angelman syndrome.These include:

• frequent laughter and smiling, often with little stimulus
• being easily excitable, often flapping the hands
• being restless (hyperactive)
• having a short attention span
• problems sleeping and needing less sleep than other children
• a particular fascination with water

By around two years of age, an abnormally small head which is flat at the back (microbrachycephaly) will be noticeable in some children with Angelman syndrome. Children with Angelman syndrome may also start to have seizures (fits)around this age.

Other possible featuresof the syndrome include:

• tendency to stick the tongue out
• crossed eyes (strabismus)
• pale skin, and light-coloured hair and eyes in some children
• a wide mouth with widely spaced teeth
• a side-to-side curvature of the spine ( scoliosis )
• walking with arms in the air

Some young babies with Angelman syndrome may have problems feeding because they're unable to co-ordinate sucking and swallowing. In such cases, a high-calorie formula may be recommended to help the baby gain weight.Babies with Angelman syndromemay need to be treated for reflux.