Prevalence and characteristics of dystrophin defects in adult male patients with dilated cardiomyopathy

Abstract

Although the overall prevalence of dystrophin defects in our consecutive DCM male series is low (6.5%), immunohistochemical and molecular studies are essential to identify protein and gene defects; screening studies are justified to define prevalence, clinical profile and genotype-phenotype correlation.

Gene Mutations in Adult Japanese Patients With Dilated Cardiomyopathy

“…In addition, less severe mutations of dystrophin, such as missense mutations, may be associated with the sporadic form of DCM. 35 The clinical characteristics of DCM caused by dystrophin mutations have X-linked inheritance and are associated with increased CK concentrations, 29,32 as seen in the present study. Epidemiologic studies in Japan have reported that the male-to-female ratio is 2.6 for DCM, 1 which is comparable with the current finding demonstrating X-linked inheritance in several patients with dystrophin mutations.…”

“…28,29 In an earlier Japanese study, Shiga et al reported that no mutation of the muscle promoter/first exon region of the dystrophin gene was identified in 92 patients with DCM, 30 but they did not study the other regions of the gene. In contrast, we identified mutations in exons 45-52 in the dystrophin gene in 3 of 68 male patients (4.4%) with DCM in the present study, which suggests that analysis for mutations in exons 45-52 in the dystrophin gene may be more important in Japanese patients with DCM.…”

The mitochondrial DNA mutation T12297C affects a highly conserved nucleotide of tRNALeu(CUN) and is associated with dilated cardiomyopathy

“…In this clinical cardiology setting, the only practical guide addressing to a possible mitochondrial origin of the cardiomyopathy is the endomyocardial biopsy, with ultrastructural and mitochondrial enzyme studies. EMB samples must be used to exclude the inflammatory or dystrophic 18 or autoimmune, etc. origin of the disease.…”

Muscular Dystrophies: Key Elements for Everyday Diagnosis and Management

“…28,30,31 Life expectancy is severely conditioned by the presence of the cardiomyopathy, closely related to the type of dystrophin gene mutation. 32,33 Heart transplantation is often required. 34 …”

“…Mutations responsible for X-linked cardiomyopathy are confined into two regions of the dystrophin gene: i) mutations at the 5' end of the gene; 41 and ii) mutations in the spectrin-like dystrophin rod domain. 42 Mutations in NH2 domain seem to be associated to a more severe phenotype, 32 because patients with these mutations are unable to compensate the lack of M isoform in the heart, upregulating the B and P isoforms of dystrophin, as happens in the muscle.…”