Characteristic epileptic seizures and EEG abnormalities are reported in three siblings with Angelman syndrome from the Kansai University Otokoyoma Hospital, Kyoto; and the Nagasaki University School of Medicine, Japan. Seizures were generalized, and interictal EEG findings included 2- to 3-Hz high-voltage slow waves bioccipitally and sporadic slow spike wave complexes bifrontally. EEG minor epileptic status occurred in a 38 month old sib and was responsive to clonazepam. The thresholds of wave V in auditory brainstem responses were increased, and the latency of wave I was prolonged in all 3 siblings. Chromosome studies were normal, but DNA deletion of the GABA receptor subunit gene was reported (Saitoh S) in the maternal grandfather, mother, and 3 siblings. [1]
COMMENT. Angelman syndrome is characterized by brachycephaly, microcephaly, mental retardation, jerky puppet-like movements of extremities, inappropriate laughter, and seizures. Seizures are generalized in 90% of patients. Deafness has been reported previously, but the abnormal auditory brain stem responses recorded in this study appear to be unique.
Eight sporadic cases of Angelman syndrome associated with chromo-some 15ql2 deletion are reported from the Central Hospital, and Kobato Gakuen, Aichi Prefectural Colony, Japan [2]. Angelman syndrome is included in the etiology of West, Lennox-Gastaut and other infantile-onset epileptic syndromes.