Speech and Language
Some AS children seem to have enough comprehension to be able to speak, but in even the highest functioning, conversational speech does not develop. Clayton-Smith [1] reported that a few individuals spoke 1-3 words, and in a survey of 47 individuals, Buntinx et al.[2] reported that 39% spoke up to 4 words, but it was not noted if these words were used meaningfully. Children with AS caused by uniparental disomy may have higher verbal and cognitive skills; at times use of 10-20 words may occur, although pronunciation may be awkward [3]. Finally, it is now clear that some AS individuals with a mosaic imprinting defect can have use of many words (up to 50 or 60) and a few of them can speak in simple sentences [4].
The speech disorder in AS has a somewhat typical evolution. Babies and young infants cry less often and have decreased cooing and babbling. A single apparent word, such as "mama," may develop around 10-18 months but it is used infrequently and indiscriminately without symbolic meaning. By 2-3 years of age, it is clear that speech is delayed but it may not be evident how little the AS child is verbally communicating; crying and other vocal outbursts may also be reduced. By 3 years of age, higher functioning children with AS are initiating some type of non-verbal language and use nonverbal gestures as a way in which to compensate for their expressive language deficits. Some point to body parts and indicate some of their needs by use of simple gestures, but they are much better at following and understanding commands. Others, especially those with severe seizures or extreme hyperactivity, cannot be attentive enough to achieve the first stages of communication, such as establishing sustained eye contact. The nonverbal language skills of AS children vary greatly, with the most advanced children able to learn some sign language and to use such aids as picture-based communication boards. Please refer to the section in this document on Communication for more details about the language and communications abilities, and the therapy approaches, for those with AS.
1. Clayton-Smith J. Clinical research on Angelman syndrome in the United Kingdom: observations on 82 affected individuals. Am J Med Genet, 1993. 46(1): p. 12-5.
2. Buntinx IM, Hennekam RC, Brouwer OF, et al. Clinical profile of Angelman syndrome at different ages. Am J Med Genet, 1995. 56(2): p. 176-83.
3. Bottani A, Robinson WP, DeLozier-Blanchet CD, et al. Angelman syndrome due to paternal uniparental disomy of chromosome 15: a milder phenotype? Am J Med Genet, 1994. 51(1): p. 35-40.
4. Nazlican H, Zeschnigk M, Claussen U, et al. Somatic mosaicism in patients with Angelman syndrome and an imprinting defect. Hum Mol Genet, 2004. 13(21): p. 2547-55.