Female ; Humans ; Muscular Dystrophy, Duchenne/genetics*

Cardiomyopathy, Dilated/genetics* ; Humans ; Muscular Dystrophy, Duchenne

Duchenne muscular dystrophy (DMD) is a lethal muscular disorder caused by mutations in the dystrophin gene for which no mutation targeted therapy has been available so far. However, a new method named exon-skipping mediated by antisense oligonucleotides has considerable potential for DMD therapy. In this review, the principle, basic research and clinical research of exon-skipping are mainly summarized.
Animals ; Exons ; genetics ; Humans ; Muscular Dystrophy, Duchenne ; genetics ; therapy ; Oligonucleotides, Antisense ; genetics

OBJECTIVE: To explore the genetic basis of a Chinese pedigree affected with Becker muscular dystrophy (BMD) with myalgia as the main feature. METHODS: Clinical data of the patients and results of auxiliary examinations were retrospectively analyzed. Multiplex ligation-dependent probe amplification and high-throughput sequencing were used to detect potential variants. Sanger sequencing was used to verify the results. RESULTS: The clinical manifestations of the proband included myalgia and elevated serum creatine kinase, which is similar to another patient from the pedigree. Genetic testing revealed that the two patients both harbored hemizygous deletions of exons 10 to 29 of the DMD gene, for which the mother was a carrier. The same deletion was not found in his father. Based on the guidelines from American College of Medical Genetics and Genomics, the deletion was predicted to be pathogenic (PVS1+PM2+PP1). CONCLUSION Myalgia with elevated serum CK may be atypical clinical manifestations of BMD and may be associated with variants in the rod domain of the DMD gene. The deletion of exons 10 to 29 of the DMD gene probably underlay the BMD in this pedigree.
China ; Dystrophin/genetics* ; Female ; Genetic Testing ; Humans ; Muscular Dystrophy, Duchenne/genetics* ; Myalgia/genetics* ; Pedigree ; Retrospective Studies

OBJECTIVE: To carry out pedigree analysis for a rare child with comorbid X-linked ichthyosis (XLI) and Duchenne muscular dystrophy (DMD). METHODS: Whole exome sequencing (WES) and multiple ligation-dependent probe amplification (MLPA) were used to detect potential deletions in the STS and DMD genes. RESULTS: The proband was found to harbor hemizygous deletion of the STS gene and exons 48 to 54 of the DMD gene. CONCLUSION The child has comorbid XLI and DMD, which is extremely rare.
Child ; Dystrophin/genetics* ; Exons ; Gene Deletion ; Genetic Testing ; Humans ; Ichthyosis/genetics* ; Muscular Dystrophy, Duchenne/genetics* ; Mutation

OBJECTIVETo clarify the nature of a DMD splice acceptor mutation c.2381-3T>C.

METHODSGenomic DNA was extracted from 5 members of a family affected with DMD. For an obligatory carrier, after excluding gross deletion and duplication of the DMD gene with multiplex ligation-dependent probe amplification (MLPA) method, all coding and splice site sequences of the DMD gene were analyzed with Next Generation Sequencing followed by confirmation with targeted Sanger sequencing. Mutations of the carrier were detected in other 4 members. For the splice site mutation, mini-gene was constructed and expressed in vitro to detect the number of transcript and cDNA sequence.

RESULTSA known nonsense mutation (c.8038C>T, p.Arg2680Ter) was identified in the carrier, her sister and the mother. The rest 4 members, except for the mother from the first generation, have all carried the c.2381-3T>C mutation. The latter has been described as a splice site mutation to cause DMD. One of 135 male adults without DMD was also detected to have carried the c.2381-3T>C mutation. No additional transcript was produced by the mini-genes containing c.2381-3T>C mutation.

CONCLUSIONThe c.8038C>T（p.Arg2680Ter）mutation of DMD gene probably underlies the disease in this family. The presence of the c.2381-3T>C mutation in a asymptomatic male and a non-DMD male control, together with the normal in vitro expression of the mini-gene carrying the c.2381-3T>C, strongly suggested that the c.2381-3T>C mutation collected in the Human Gene Mutation Database is a rare SNP without significant pathogenicity.

Dystrophin ; genetics ; Humans ; Male ; Muscular Dystrophy, Duchenne ; genetics ; Mutation ; Polymorphism, Single Nucleotide

OBJECTIVETo investigate the clinical and lab features of sibling brother and sister both with Duchenne muscular dystrophy (DMD).

METHODSWe conducted comprehensive clinical and lab investigations including the test of serum enzymes, electromyography (EMG), electrocardiography, color Doppler echocardiography, HE staining of skeletal muscles, immunohistochemical study of dystrophin and utrophin, multiple ligation probe amplification (MLPA) on exon 1-79 of dystrophin gene, and short tandem repeat-poly- merase chain reaction of CA repeats located in dystrophin gene.

RESULTSThese two patients were confirmed to suffer from DMD. They were characterized by typical features of DMD including typical clinical manifestations, increased serum enzymes, EMG presenting myogenic impairment, HE staining presentation belonging to DMD, negative dystrophin in brother, and inconstantly positive on the sarcolemma of sister. Furthermore, no deletion or duplication was found in the 1-79 exons of dystrophin gene. The suffering brother and sister carried the same maternal X chromosome.

CONCLUSIONSCarriers of DMD gene show typical clinical and laboratory manifestations of DMD. Comprehensive examinations should be performed for such carriers.

Dystrophin ; genetics ; Female ; Genetic Linkage ; Heterozygote ; Humans ; Male ; Muscular Dystrophy, Duchenne ; genetics ; metabolism ; physiopathology ; Siblings

OBJECTIVETo explore the correlation between genotypes and phenotypes in Chinese patients with pseudohypertrophic muscular dystrophy.

METHODSPatients with Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) were diagnosed clinically. Multiplex ligation-dependent probe amplification (MLPA) were performed to detect potential DMD gene mutations. The results were analyzed statistically.

RESULTSAmong 280 patients, 238(85.0%) were diagnosed with DMD, 35(12.50%) were diagnosed with BMD and 7(2.5%) were diagnosed with intermediate muscular dystrophin (IMD). Among these, 252(92.31%) were in-frame mutations, and 21(7.69%) were out-of-frame mutations. Twelve patients with DMD have carried in-frame mutations, 9 with BMD have carried frame-shift mutations, and 7 IMD patients have carried frame-shift mutation.

CONCLUSIONMost of the genotypes and phenotypes of DMD have complied with the reading-frame hypothesis. Patients with BMD with frame-shift mutations may facilitate understanding of the pathogenesis of DMD, and provide a theoretical basis for clinical therapy.

Dystrophin ; genetics ; Exons ; Genetic Association Studies ; Genotype ; Humans ; Muscular Dystrophy, Duchenne ; diagnosis ; genetics ; Mutation ; Phenotype

Child ; DNA Mutational Analysis ; Dystrophin ; genetics ; Exons ; Humans ; Male ; Muscular Dystrophy, Duchenne ; genetics ; Mutation

OBJECTIVE: To explore the clinical features and genetic diagnosis of two cases with rare diseases and X chromosome abnormalities. METHODS: Multiple ligation-dependent probe amplification (MLPA) and karyotype analysis were carried out on an 8-year-old girl who was diagnosed with Duchenne muscular dystrophy. Karyotype analysis and PCR assay for SRY and AZF genes were carried out for a-2-month-old male infant with short penis. RESULTS: The girl, who featured short stature and cubitus valgus, was diagnosed as Turner syndrome with a karyotype of 46,X,i(Xq). The male infant was detected with a karyotype of 45,X, with presence of SRY gene but absence of AZF gene. CONCLUSION Both cases may be associated with abnormalities of X chromosome. Genetic testing can facilitate early diagnosis and clinical intervention for such patients.
Chromosomes, Human, X ; Humans ; Infant ; Karyotyping ; Male ; Muscular Dystrophy, Duchenne ; genetics ; Rare Diseases ; Turner Syndrome ; genetics