A cohort of patients with DMD with exon 2 duplication

Duplications of the DMD gene encoding dystrophin are rare and represent a real therapeutic challenge. An American team compiled the clinical and biological data of 66 patients with this relatively uncommon genotype:

  • 61% of them had a DMD-like phenotype, 30% a Becker-like phenotype and 9% an intermediate phenotype,
  • 3/4 of them were treated with long-term corticosteroids,
  • overall, their evolutionary trajectory differed markedly from that of the historical cohort of DMD patients.

These data will be useful for conceptualizing future therapeutic trials.


Italian DMD Network and the United Dystrophinopathy Project (UDP). Phenotypic Spectrum of Dystrophinopathy Due to Duchenne Muscular Dystrophy Exon 2 Duplications. Zambon AA, Waldrop MA, Alles R, et al. Neurology. 2021 Dec 22:10.1212/WNL.0000000000013246.