Case report: Angelman syndrome in an individual with a small SMC(15) and paternal uniparental disomy: A case report with reference to the assessment of cognitive functioning and autistic symptomatology

The case of a 15-year-old male with Angelman syndrome, paternal uniparental disomy of chromosome 15, and a small supernumerary marker chromosome is discussed. Assessment of cognitive functioning revealed an uneven profile of ability across different domains; in particular, receptive language ability was found to be superior to expressive language ability, whilst both gross and fine motor skills were found to be relatively well developed. Assessment using the Autism Diagnostic Observation Schedule showed very little evidence of autistic symptomatology. The patient showed an interest in social interaction and used a variety of methods to communicate, including some gestures and several single words. A clinical history revealed febrile convulsions during childhood but an absence of seizures in the previous 5 years. The patient was not hypopigmented, and height, weight, and head circumference were within the normal range for his age. The implications of these features are discussed in the context of previous work describing a milder phenotype in nondeletion cases of Angelman syndrome and work that has examined the prevalence of autism spectrum disorders amongst individuals with Angelman syndrome.