Angelman syndrome: Genetic mechanisms and relationship to Prader-Willi syndrome

Abstract

Angelman syndrome (AS) has been localised to a region on the proximal long arm of chromosome 15 - bands q11-13 - previously designated as the Prader-Willi chromosome region (PWCR). Research points to two distinct regions within the PWCR, one for PWS and one for AS. There is currently no candidate gene for AS. Genetic mechanisms in Angelman syndrome are complex. At present, three mechanisms are recognised: maternal deletion, paternal uniparental disomy and a nondeleted, nondisomic form. The importance of establishing the mechanism lies in the different recurrence risks which apply to each type.