INTRANUCLEAR INCLUSIONS IN OCULOPHARYNGEAL MUSCULAR-DYSTROPHY AMONG BUKHARA JEWS

We studied, by electron microscopy, muscle biopsies from seven patient s with autosomal dominant oculopharyngeal muscular dystrophy (OPMD) be longing to the recently described Bukhara-Jewish cluster. Typical tubu lofilamentous intranuclear inclusions (INI) of 8.5 nm outer diameter w ere present in all cases. The INI were observed in 4.5 +/- 1.8% of the nuclei in five patients. In the other two, they occurred in 9.5 +/- 0 .5% of the nuclei and often occupied a larger nuclear area, These two patients, offspring of intermarriage between affected cousins, had an unusually severe form of OPMD beginning in their early 30s, suggesting homozygote state. Our results confirm that INI are pathognomonic for OPMD and suggest that their frequency may be quantitatively related to the number of abnormal DNA copies.