Duchenne muscular dystrophy (DMD) is an X-linked recessive disorder characterized by progressive muscle degeneration and weakness caused by variations in the DMD gene, including deletions (68%), duplications (10%), small variants such as point mutations (22%), and rare complex rearrangements (<0.5%), which may vary slightly in different regions (1–3). The gene discussed is DMD; the disease is Duchenne muscular dystrophy.