DMD and Duchenne muscular dystrophy: This revealed a pathogenic variant in exon 55 (NM_004006.3, DMD: g.1716784_1716785del; c.8064_8065delTA; p.(His2688GlnfsTer21)), classified as pathogenic according to the American College of Medical Genetics and Genomics (ACMG) criteria (PVS1—Pathogenic Very Strong 1, PM2—Pathogenic Moderate 2, PS4—Pathogenic Strong 4), thus confirming the diagnosis of Duchenne muscular dystrophy at the age of three [15].