APOPTOTIC NUCLEAR DEGENERATION IN MARINESCO-SJOGREN-SYNDROME

In 12 patients with the clinical characteristics of Marinesco-Sjogren syndrome including an autosomal recessive inheritance, congenital cata racts, mental retardation, cerebellar ataxia and progressive muscle we akness, the most common pathological finding was rimmed vacuole format ion comprising from 0.1% to 10% of fibers in their muscle biopsy sampl es. The nuclear changes varied from condensed chromatin granules to va cuolation with amorphous inclusions which were predominantly seen in y ounger patients with prominent rimmed vacuoles, suggesting a close rel ationship between nuclear change and rimmed vacuole formation. From th e severe destructive changes in nuclei, we speculated that the nuclear changes in Marinesco-Sjogren syndrome play a primary role in muscle d egeneration resulting in myofibrillar disorganization and rimmed vacuo le formation. In 2 patients, the TUNEL method demonstrated scattered m yonuclei with fragmented DNA, but ''ladder formation'' was not found, probably because of the small numbers of nuclei with fragmented DNA. N uclear degeneration with focal myofibrillar degeneration seen in these muscle samples suggests that the apoptotic process may occur in muscl e disorders, especially in diseases with rimmed vacuole formation.