Novel Insights Into DMD -Associated Dilated Cardiomyopathy.

Dystrophinopathies are a group of genetic disorders caused by pathogenic variants in the DMD gene, which encodes the large cytoskeletal protein dystrophin. The dystrophin protein is one of the largest known proteins in the human body consisting of 3427 amino acids and 79 exons. As part of the dystrophin-glycoprotein complex, its main function is to provide structural support and stability to skeletal muscle fibers, and to help maintain the integrity of cardiomyocytes.1 The most common gene associated with X-linked dilated cardiomyopathy (XLDCM) is the DMD gene, thus making XLDCM a specific form of dystrophinopathy that is distinct from other dystrophinopathies like Duchenne and Becker muscular dystrophy.2 XLDCM's primary feature is dilated cardiomyopathy without significant skeletal myopathy, whereas Duchenne and Becker muscular dystrophy both primarily manifest as skeletal muscle weakness with cardiac involvement in adolescence or early adulthood. Each disease entity has the potential for rapid progression of dilated cardiomyopathy to end-stage heart failure, thus highlighting the importance of awareness and need for early recognition of this group of genetic disorders.