Congenital nemaline myopathy is associated with a shift towards slow myosin light chain composition in muscle fibers.
Answers are grounded in this paper and cite their sources.
Does not change biopsy interpretation or management in nemaline myopathy; leaves open whether slow myosin shifts drive weakness or represent adaptation.
Muscle biopsies from two familial and one sporadic case with congenital nemaline myopathy and seven healthy family members were examined for myosin composition. Myosin was characterized with respect to light chain (LC) composition by one-dimensional and two-dimensional electrophoresis, and by immunologic methods (enzyme-linked immunosorbent assay [ELISA]), using specific antibody for rabbit fast myosin LCl (LC1F). Type I fiber predominance was associated with the substitution of a hybrid, predominantly "slow" to a virtually pure "slow" myosin LC pattern for the "mixed" pattern found with myosin of normal muscle. Muscle myosin from the relatives had apparently normal light chain composition.
No takes yet. Share an insight, caveat, or question.
Volpe et al. (1982) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: