DMD and Becker muscular dystrophy: Dystrophin is encoded by DMD. Deletions (in about 65% of patients), duplications (in about 10% of patients), point mutations (in about 10% of patients), or other smaller rearrangements can disrupt the open reading frame of DMD, leading to premature termination of its translation,3, 4 whereas deletions or duplications that maintain the open reading frame can lead to truncated but functional dystrophin, which underlies the milder disorder Becker muscular dystrophy (BMD).5