An Angelman syndrome clinic: report on 24 patients J Paediatr Child Health. 1996 Apr;32(2):94-8. doi: 10.1111/j.1440-1754.1996.tb00902.x. Authors R P Leitner 1 ... Objective: Angelman syndrome (AS) is a rare congenital neurodevelopmental disorder with complex genetic aetiology. Diagnosis may be difficult and there is severe life-long disability..