Duchenne muscular dystrophy is a fatal X-linked disease caused by mutations in the DMD gene, leading to the absence of dystrophin and progressive degeneration of skeletal and cardiac muscles. Pigs lacking DMD exon 52 (DMDΔ52) are a clinically severe model for DMD, mimicking molecular, functional, and pathological hallmarks of the human disease. Dystrophin expression can be restored by additionally deleting exon 51 (DMDΔ51-52), which reframes DMD transcripts and alleviates pathological alterations. DMDΔ51-52 pigs model Becker muscular dystrophy (BMD), a milder and slower-progressing form of muscle degeneration.