A novel DMD splicing mutation found in a family responsible for X-linked dilated cardiomyopathy with hyper-CKemia

This study was aimed to detect a new mutation responsible for X-linked dilated cardiomyopathy with hyper-CKemia. We studied a proband who presented with cardiac symptoms with hyper-CKemia, but no clinical skeletal involvement in physical examination, laboratory tests, electromyography, echocardiography, and magnetic resonance imaging (MRI) of cardiac muscles. Muscle biopsy for histopathology and immunohistochemistry for accessing sarcolemma changes. The next-generation sequencing and bioinformatics analysis were performed on the patient and Sanger sequencing was confirmed on the other 6 unaffected families. The clinic investigations illustrated a dilated cardiomyopathy. Histopathology and immunohistochemistry showed dystrophic changes and an obvious reduction of dystrophin-N and δ-sarcoglycan, respectively. One hemizygous splicing pathogenic mutation c. 31 + 1G > C of exon 1 in the DMD gene (chrX33229398, NM₀0 4006) was finally identified in the patient and his nephew, but it was carried in his mother and sister. A novel small mutation was identified at the first exon-intron boundary splicing site by next-generation sequencing and bioinformatics analysis.