DMD and Duchenne muscular dystrophy: Dystrophin expression is eliminated in both dystrophic strains, yet numerous variations can be found between the dystrophic strains that differentially affect functional and structural outcomes17, such as expansion of revertant fibers19, expression of shorter isoforms of dystrophin in the mdx strain20, and abnormal electroretinograms in mdx52 similar to those in DMD patients16, 18.