DMD: a meta-analysis points to the increased risk of heart complications from certain deletions in the DMD gene

Duchenne muscular dystrophy (DMD) is the most common neuromuscular disease in boys while Becker’s muscular dystrophy (BMD), a milder and less progressive allelic variant, is much rarer. Both are recessive diseases linked to the X chromosome with, in one case, a complete absence of dystrophin (DMD) and in the other, a partial deficiency of dystrophin (BMD). The involvement, to varying degrees, of the cardiac muscle is an integral part of the clinical phenotype, with a date of onset and a severity that varies widely among individuals. In addition, with improved management and increased survival of patients with DMD, a higher frequency of cardiac complications is observed, mainly in the form of cardiomyopathy.

In an article published in October 2020, Chinese researchers carried out a meta-analysis of the medical literature up to August 2019, on the importance of these complications and their possible correlations with the molecular defects in the DMD gene encoding dystrophin. Of 3,450 articles scrutinized, 18 captured the attention of the authors. These included data from a total of 2,661 patients with DMD or BMD, of whom nearly half (1,324) had varying degrees of cardiac damage. In general, an increased incidence of cardiac complications was noted in the event of deletions of the DMD gene, and in particular when these involved exons 45 and 46.

 

Cardiac Phenotype-Genotype Associations in DMD/BMD: A Meta-Analysis and Systematic Review. H Zhou, M Fu, B Mao, L Yuan. Pediatr Cardiol. 2020 (Oct).