The mdx mouse model contains a nonsense mutation in exon 23 of the mouse Dmd gene and is the most widely used preclinical DMD model (Bulfield et al., 1984; Willmann et al., 2009), providing a good balance of throughput and recapitulation of measurable phenotypic deficits seen in humans (e.g. central myonuclei, fibrosis and cardiomyopathy) (van Putten et al., 2020). This evidence concerns the gene DMD and Duchenne muscular dystrophy.