Abstract
Members of a large French-Canadian family were found to have the cardinal features of the oculopharyngeal syndrome, including ptosis and dysphagia, which usually began late in life and progressed slowly. Weakness of facial, extraocular, and limb-girdle muscles occurred in a proportion of affected individuals. Mechanical and cineradiographlc studies of swallowing showed that the function of the striated muscle portions of the hypo-pharynx and upper esophagus was impaired. Electromyography, serum muscle enzyme determinations, and muscle biopsy specimens offered suggestive, but not definitive, evidence that the disorder was primarily myopathic. Genetic analysis revealed that the disorder was transmitted in straightforward dominant fashion. All of the numerous French-Canadian family groups with the oculopharyngeal syndrome are now known to be related to one another, and presumably share the same underlying biochemical defect, which has yet to be elucidated.