Dystrophin-positive fibers in Duchenne dystrophy: origin and correlation to clinical course

• Published in: Muscle & nerve Vol. 18; no. 10; p. 1115
• Main Authors: Fanin, M, Danieli, G A, Cadaldini, M, Miorin, M, Vitiello, L, Angelini, C
• Format: Journal Article
• Language: English
• Published: United States 01.10.1995
• Subjects: Biopsy; Child; Child, Preschool; DNA, Complementary; Dystrophin - genetics; Dystrophin - metabolism; Dystrophin - ultrastructure; Humans; Immunohistochemistry; Models, Genetic; Muscle Fibers, Skeletal - immunology; Muscle Fibers, Skeletal - metabolism; Muscle Fibers, Skeletal - pathology; Muscular Dystrophies - genetics; Muscular Dystrophies - metabolism; Muscular Dystrophies - pathology; Mutation; Severity of Illness Index; Time Factors
• ISSN: 0148-639X
• DOI: 10.1002/mus.880181007

In 132 DMD muscle biopsies we investigated the presence of dystrophin-positive fibers and the relationship of dystrophin immunohistochemical pattern to the clinical severity of the disease. Reverted fibers were detected in 37% of patients; their prevalence increased significantly in each biopsy with age of patients. We suggest that reversion occurs in satellite cells, when muscle differentiation is completed. The longitudinal extent of dystrophin-positive domain spans a maximum length of 900 microns. No correlation was found between the presence of reverted fibers and the clinical severity of DMD, whereas a milder form of Duchenne dystrophy was observed in patients showing a faint reaction in all fibers. The occurrence of reverted fibers is independent of the type of gene mutation; however, a higher proportion of cases with reverted fibers was found among patients with gene duplications.