Although the mdx mouse historically served as the standard animal model to investigate causes and potential cures for DMD, the murine mdx phenotype is much milder than human or canine forms [9], particularly on the C57Bl10 background due to the upregulation of other cytoskeletal proteins, i.e., utrophin, to provide cellular stability [10], as well as a combination of genetic modifiers that alter disease progression. Here, UTRN is linked to Duchenne muscular dystrophy.