Two major allelic forms of myosin light chain-1 in strains of normal and dystrophic chickens

Abstract

Evidence is presented from electrophoresis and peptide‐mapping for the existence of two major allelic forms of myosin light chain‐1 in the fast white muscle fibers of domestic chickens. One form predominates in birds of White Leghorn stock, the other in birds of New Hampshire Red stock. The two light chain‐1 forms were invariant during development. Variability was not detected in light chains‐2 or ‐3. The distribution of the two forms in two strains homozygous for the am gene for muscular dystrophy—Connecticut dystrophic and line 413—and their controls, White Leghorn and line 412, respectively, while clearly unrelated to avian dystrophy, emphasizes the heterogeneity in background genes of these non‐inbred lines and indicates caution in their use in studies of avian dystrophy.