Profiling of pathogenic variants in Japanese patients with sarcoglycanopathy.

Background: Sarcoglycanopathies (SGPs) are limb-girdle muscular dystrophies (LGMDs) that can be classified into four types, LGMDR3, LGMDR4, LGMDR5, and LGMDR6, caused by mutations in the genes, SGCA, SGCB, SGCG, and SGCD, respectively. SGPs are relatively rare in Japan. This study aims to profile the genetic variants that cause SGPs in Japanese patients.

A Case of Oculopharyngeal Muscular Dystrophy Caused by a Novel PABPN1 c.34G > T (p.Gly12Trp) Point Mutation without Polyalanine Expansion.

Immediately after the initial methionine codon, the PABPN1 gene encodes a stretch of 10 alanines, 1 glycine, and 2 alanines. Oculopharyngeal muscular dystrophy (OPMD) is caused by the expansion of the first 10 alanine stretches. The only exception is the missense mutation of glycine at the 12th residue into alanine, which elongates the stretch to 13 alanines by connecting the first and second stretch with the addition of one alanine in between, indicating that the expansion or elongation of the alanine stretch results in OPMD.

Sporadic Myotonic Dystrophy Type 2 in a Japanese Patient.

We herein report a Japanese patient with myotonic dystrophy type 2 (DM2), which is rare in Japan. A 64-year-oldman had proximal muscle weakness and grip myotonia. Electromyography showed myotonic discharges, but dystrophia-myotonica protein kinase (DMPK) was negative for CTG repeats.

Intranuclear inclusions in muscle biopsy can differentiate oculopharyngodistal myopathy and oculopharyngeal muscular dystrophy.

Oculopharyngodistal myopathy (OPDM) and oculopharyngeal muscular dystrophy (OPMD) are similar and even believed to be indistinguishable in terms of their myopathological features. To address the diagnostic gap, we evaluated the muscle biopsy samples for p62 expression by immunohistochemistry and compared the occurrence and the frequency of intranuclear inclusions among the individuals with OPDM (harboring CGG repeat expansion in LRP12 (n = 19), GIPC1 (n = 6), or NOTCH2NLC (n = 7)), OPMD (n = 15), and other rimmed vacuolar myopathies. We found that myonuclei with p62-positive intra-nuclear inclusions (myo-INIs) were significantly more frequent in OPMD (11.

Frontal lobe-dominant cerebral blood flow reduction and atrophy can be progressive in Duchenne muscular dystrophy.

This study aimed to clarify the characteristics and progressive changes of brain image abnormalities in Duchenne muscular dystrophy (DMD). Brain images of 39 adult patients (median age, 24 years) were retrospectively reviewed, along with intellectual and/or neurodevelopmental test results. On magnetic resonance imaging (n = 13), atrophy of the frontal lobe, pars opercularis (without other frontal atrophy), and cerebellum was observed in 6, 1, and 1 patients, respectively.

Intranuclear inclusions in skin biopsies are not limited to neuronal intranuclear inclusion disease but can also be seen in oculopharyngodistal myopathy.

Aims: Oculopharyngodistal myopathy (OPDM) is caused by the expansion of CGG repeats in NOTCH2NLC (OPDM_NOTCH2NLC) GIPC1 (OPDM_GIPC1), or LRP12 (OPDM_LRP12). Neuronal intranuclear inclusion disease (NIID) is clinically distinct from OPDM but is also caused by the expansion of CGG repeats in NOTCH2NLC, which may be an indicator of intranuclear inclusion in skin biopsy. We investigated the presence of intranuclear inclusions in skin biopsies from patients with OPDM and muscle diseases with a similar pathology to evaluate whether they will have similar diagnostic findings on skin biopsy.

A Japanese case of oculopharyngeal muscular dystrophy (OPMD) with PABPN1 c.35G > C; p.Gly12Ala point mutation.

Background: Oculopharyngeal muscular dystrophy (OPMD) is a late-onset muscular dystrophy characterised by slowly progressive ptosis, dysphagia, and proximal limb muscle weakness. A common cause of OPMD is the short expansion of a GCG or GCA trinucleotide repeat in PABPN1 gene.

Case Presentation: A 78-year-old woman presented with ptosis and gradually progressive dysphagia.

A symptomatic male carrier of Duchenne muscular dystrophy with Klinefelter's syndrome mimicking Becker muscular dystrophy.

Duchenne and Becker muscular dystrophy (DMD/BMD) are commonly inherited muscle disorders. We report a 31-year-old male who had muscle symptoms with left-right differences and intellectual disability. He was diagnosed with BMD at age 15 primarily based on muscle biopsy findings.

Clinicopathologic Features of Oculopharyngodistal Myopathy With LRP12 CGG Repeat Expansions Compared With Other Oculopharyngodistal Myopathy Subtypes.

Importance: Repeat expansion of CGG in LRP12 has been identified as the causative variation of oculopharyngodistal myopathy (OPDM). However, to our knowledge, the clinicopathologic features of OPDM with CGG repeat expansion in LRP12 (hereafter referred to as OPDM_LRP12) remain unknown.

Objective: To identify and characterize the clinicopathologic features of patients with OPDM_LRP12.

Respiratory Dysfunction in Becker Muscular Dystrophy Patients: A Case Series and Autopsy Report.

Background: Few studies have examined respiratory dysfunction in patients with Becker muscular dystrophy (BMD).

Objective: This study aimed to examine the characteristics of respiratory dysfunction in patients with BMD.

Methods: The present retrospective study assessed respiratory parameters of adult BMD patients using medical records and compared these parameters with various patient characteristics to identify correlations.

Clinical, pathological, imaging, and genetic characterization in a Taiwanese cohort with limb-girdle muscular dystrophy.

Background: Limb-girdle muscular dystrophy (LGMD) is a genetically heterogeneous, hereditary disease characterized by limb-girdle weakness and histologically dystrophic changes. The prevalence of each subtype of LGMD varies among different ethnic populations. This study for the first time analyzed the phenotypes and genotypes in Taiwanese patients with LGMD in a referral center for neuromuscular diseases (NMDs).

Severe cardiac involvement with preserved truncated dystrophin expression in Becker muscular dystrophy by +1G>A DMD splice-site mutation: a case report.

Becker muscular dystrophy (BMD) is caused by specific mutations in the DMD gene that causes progressive muscle weakness and primarily affects skeletal and cardiac muscle. Although cardiac involvement is a significant cause of mortality in BMD, the genetic-phenotype correlation for skeletal and cardiac muscles has not been elucidated. Here, we described a 39-year-old man with BMD, who presented with subtle skeletal muscle weakness in the right leg in his 20s and underwent left ventricular restoration for severe dilated cardiomyopathy at the age of 29.

Psychiatric and neurodevelopmental aspects of Becker muscular dystrophy.

Little is known about the relationship between Becker Muscular Dystrophy (BMD) and mental disorders. This study aimed to clarify whether BMD is a risk factor for psychiatric diseases. We asked genetically or immunohistochemically confirmed BMD patients to participate in the study interview.

Social involvement issues in patients with Becker muscular dystrophy: A questionnaire survey of subjects from a patient registry.

Background: Little is known about the relationship between Becker Muscular Dystrophy (BMD) and developmental problems, school life, employment, and mental problems. We aimed to clarify whether BMD is a risk factor for developmental disorders, problematic behavior, psychiatric diseases, and other social difficulties in school life and employment.

Methods: Adults with genetically or immunohistochemically confirmed BMD from the Registry of Muscular Dystrophy in Japan (REMUDY) were asked to complete a questionnaire regarding patient history, school life, employment, and mental problems.

Corrigendum: Genetic diagnosis of Duchenne/Becker muscular dystrophy using next-generation sequencing: validation analysis of DMD mutations.

This corrects the article DOI: 10.1038/jhg.2016.

Induction of Pluripotent Stem Cells from a Manifesting Carrier of Duchenne Muscular Dystrophy and Characterization of Their X-Inactivation Status.

Three to eight percent of female carriers of Duchenne muscular dystrophy (DMD) develop dystrophic symptoms ranging from mild muscle weakness to a rapidly progressive DMD-like muscular dystrophy due to skewed inactivation of X chromosomes during early development. Here, we generated human induced pluripotent stem cells (hiPSCs) from a manifesting female carrier using retroviral or Sendai viral (SeV) vectors and determined their X-inactivation status. Although manifesting carrier-derived iPS cells showed normal expression of human embryonic stem cell markers and formed well-differentiated teratomas in vivo, many hiPS clones showed bi-allelic expression of the androgen receptor (AR) gene and loss of X-inactivation-specific transcript and trimethyl-histone H3 (Lys27) signals on X chromosomes, suggesting that both X chromosomes of the hiPS cells are in an active state.

Duchenne muscular dystrophy in a female with compound heterozygous contiguous exon deletions.

Females with Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) mutations rarely exhibit clinical symptoms from childhood, although potential mechanisms for symptoms associated with DMD and BMD in females have been reported. We report the case of a female DMD patient with a clinical course indistinguishable from that of a male DMD patient, and who possessed compound heterozygous contiguous exon deletions in the dystrophin gene. She exhibited Gowers' sign, calf muscle hypertrophy, and a high serum creatine kinase level at 2 years.

Novel TK2 mutations as a cause of delayed muscle maturation in mtDNA depletion syndrome.

Recessive mutations in TK2 cause a severe mitochondrial DNA depletion syndrome (MDS),(1) characterized by severe myopathy from early infancy. Recent reports have suggested a wider clinical spectrum including encephalomyopathic form.(1,2) We report a patient with infantile-onset fatal encephalomyopathy presenting with extreme muscle fiber immaturity.

Cardiopulmonary dysfunction in patients with limb-girdle muscular dystrophy 2A.

Introduction: Little is known about the frequency of cardiopulmonary failure in limb-girdle muscular dystrophy type 2A (calpainopathy) patients, although some studies have reported severe cardiomyopathy or respiratory failure.

Methods: To clarify the frequency of cardiopulmonary dysfunction in this patient population, we retrospectively reviewed the respiratory and cardiac function of 43 patients with calpainopathy.

Results: Nine of the 43 patients had forced vital capacity (FVC) < 80%, and 3 used noninvasive positive pressure ventilation.

Nuclear inclusions mimicking poly(A)-binding protein nuclear 1 inclusions in a case of inclusion body myopathy associated with Paget disease of bone and frontotemporal dementia with a novel mutation in the valosin-containing protein gene.

A middle-aged Japanese man presented with slowly progressive asymmetric weakness of legs and arm but had neither ptosis nor dysphagia. He had a family history of similar condition suggestive of autosomal dominant inheritance. A muscle biopsy showed mixture of neurogenic atrophy and myopathy with rimmed vacuoles.

Genetic diagnosis of Duchenne/Becker muscular dystrophy using next-generation sequencing: validation analysis of DMD mutations.

Duchenne and Becker muscular dystrophies (DMD/BMD) are the most common inherited neuromuscular disease. The genetic diagnosis is not easily made because of the large size of the dystrophin gene, complex mutational spectrum and high number of tests patients undergo for diagnosis. Multiplex ligation-dependent probe amplification (MLPA) has been used as the initial diagnostic test of choice.

Limb-girdle muscular dystrophy type 2a with mutation in CAPN3: the first report in Taiwan.

The autosomal recessive limb-girdle muscular dystrophy type 2A (LGMD2A) is caused by mutations in the calpain 3 (CAPN3) gene, and it is characterized by selective atrophy and weakness of proximal limb and girdle muscles. We report a 33-year-old woman with initial presentations of exercise intolerance and running difficulty at age 15 years. At presentation, waddling gait, positive Gowers' sign, and marked muscle atrophy in pelvic and leg muscles were noted.