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Mutations in the anoctamin 5 gene cause either limb girdle muscular dystrophy or Miyoshi muscular dystrophy 3 in Caucasians. We herein describe a 49-year-old Japanese man with asymmetry of the leg circumference since childhood. Muscle involvement began at the calf muscles, and later spread to the thigh and paraspinal muscles on imaging and physical examination. His external genitalia were morphologically hypoplastic. Genetic analysis identified a novel homozygous mutation, c.1178G>A (p.Trp393X), in the anoctamin 5 gene. This is the first Japanese case with Miyoshi muscular dystrophy 3 caused by an anoctamin 5 gene mutation (anoctaminopathy). The muscle impairment associated with Miyoshi muscular dystrophy 3 appears to spread from the distal to proximal lower extremities.

Frontotemporal lobar degeneration (FTLD) is a heterogeneous roup of disorders characterized by disturbances of behavior nd personality and different types of language impairment with r without concomitant features of motor neuron disease or arkinsonism [1]. FTLD is classified into three categories: fronotemporal dementia (FTD), progressive non-fluent aphasia (PNFA), nd semantic dementia (SD) [2]. Moreover, FTD is classified into wo categories: pick type and motor neuron disease (MND) type. TLD is also classified into four neuropathological categories: TLD-tau pathology type, FTLD-TDP43 pathology type, FTLD-FUS athology type, and FTLD-other type [2]. Clinical FTD-Pick type is ssociated with FTLD-tau, TDP, or FUS, and some FTLD is caused by arious genetic mutations. Limb girdle muscular dystrophy (LGMD) is a progressive myopahy with necrosis and regenerative changes in skeletal muscle. GMD Type 1D is caused by mutations in the DNAJB6 (DnaJ homolog

Here we report what is to our knowledge the first identified Japanese family afflicted by X-linked myopathy with excessive autophagy. The index case is a 52-year-old man with almost 40years of progressive proximal muscle weakness. High urinary β2 microglobulin, normal serum β2 microglobulin, autophagic vacuoles with sarcolemmal features, and a hemizygous c.164–7T>G mutation in the VMA21 gene were found. His two maternal uncles had similar clinicopathological findings. High urinary β2 microglobulin without obvious renal dysfunction might result from decreased urine acidification in the distal convoluted tubules caused by the VMA21 gene mutation. These findings might prove to be useful as a preliminary marker suggestive of X-linked myopathy with excessive autophagy.

Background GNE myopathy (also called distal myopathy with rimmed vacuoles or hereditary inclusion body myopathy) is an autosomal recessive myopathy characterised by skeletal muscle atrophy and weakness that preferentially involve the distal muscles. It is caused by mutations in the gene encoding a key enzyme in sialic acid biosynthesis, UDP- N -acetylglucosamine 2-epimerase/ N -acetylmannosamine kinase (GNE). Methods We analysed the GNE gene in 212 Japanese GNE myopathy patients. A retrospective medical record review was carried out to explore genotype–phenotype correlation. Results Sixty-three different mutations including 25 novel mutations were identified: 50 missense mutations, 2 nonsense mutations, 1 insertion, 4 deletions, 5 intronic mutations and 1 single exon deletion. The most frequent mutation in the Japanese population is c.1714G>C (p.Val572Leu), which accounts for 48.3% of total alleles. Homozygosity for this mutation results in more severe phenotypes with earlier onset and faster progression of the disease. In contrast, the second most common mutation, c.527A>T (p.Asp176Val), seems to be a mild mutation as the onset of the disease is much later in the compound heterozygotes with this mutation and c.1714G>C than the patients homozygous for c.1714G>C. Although the allele frequency is 22.4%, there are only three homozygotes for c.527A>T, raising a possibility that a significant number of c.527A>T homozygotes may not develop an apparent disease. Conclusions Here, we report the mutation profile of the GNE gene in 212 Japanese GNE myopathy patients, which is the largest single-ethnic cohort for this ultra-orphan disease. We confirmed the clinical difference between mutation groups. However, we should note that the statistical summary cannot predict clinical course of every patient.

Alpha-dystroglycanopathy is caused by the glycosylation defects of α-dystroglycan (α-DG). The clinical spectrum ranges from severe congenital muscular dystrophy (CMD) to later-onset limb girdle muscular dystrophy (LGMD). Among all α-dystroglycanopathies, LGMD type 2I caused by FKRP mutations is most commonly seen in Europe but appears to be rare in Asia. We screened uncategorized 40 LGMD and 10 CMD patients by immunohistochemistry for α-DG and found 7 with reduced α-DG immunostaining. Immunoblotting with laminin overlay assay confirmed the impaired glycosylation of α-DG. Among them, five LGMD patients harbored FKRP mutations leading to the diagnosis of LGMD2I. One common mutation, c.948delC, was identified and cardiomyopathy was found to be very common in our cohort. Muscle images showed severe involvement of gluteal muscles and posterior compartment at both thigh and calf levels, which is helpful for the differential diagnosis. Due to the higher frequency of LGMD2I with cardiomyopathy in our series, the early introduction of mutation analysis of FKRP in undiagnosed Taiwanese LGMD patients is highly recommended.

RA175/SynCAM1/Cadm1 (Cadm1), a member of the immunoglobulin superfamily, is a synaptic cell adhesion molecule that has a PDZ-binding motif at the C-terminal region. It promotes the formation of presynaptic terminals and induces functional synapses in the central nervous system. Cadm1-deficient (knockout [KO]) mice show behavioral abnormalities, including excessive aggression and anxiety, but do not show any symptoms of neuromuscular disorder, although neuromuscular junctions (NMJs) have structures similar to synapses. We have examined the expression of members of the Cadm family in the mouse muscle tissues. Cadm4 and Cadm1 were major components of the Cadm family, and Cadm3 was faintly detected, but Cadm2 was not detected by RT-PCR. Cadm4 as well as Cadm1 colocalized with alpha-bungarotoxin at the NMJs and interacted with the multiple PDZ domain protein Mupp1. Cadm4 was expressed in Cadm1-KO mice and might compensate for Cadm1 loss through interactions with Mupp1.

We report a 51-year-old man with myopathy and dementia probably caused by a novel mutation of the valosin-containing protein (VCP) gene, in the form of a p.Ala439Pro substitution. At 43 years old, he presented at least 2-year history of weakness of right ankle dorsiflexion. Findings from muscle biopsy suggested distal myopathy with rimmed vacuoles. However, no mutation in the GNE gene was identified. He complained of giving way of the knee, and muscle imaging study showed adipose tissue infiltration in the quadriceps. Ten years later, he was confined to a wheelchair and became reticent and antisocial with slightly impaired memory. A muscle CT revealed atrophy or replacement by adipose tissue in the muscles of neck, trunks and extremities muscles with laterality and variation of the degree. The magnetic resonance imaging of the brain showed bilateral frontal and temporal lobe atrophy with left dominance. Findings were compatible with inclusion body myopathy with Paget's disease of bone and frontotemporal dementia.

To report cases of chronic autoimmune necrotizing myopathy with anti-signal recognition particle antibodies (anti-SRP myopathy) initially misdiagnosed as muscular dystrophy, in particular, facioscapulohumeral muscular dystrophy (FSHD).Medical records of patients with anti-SRP myopathy in our institution were retrospectively reviewed.All 6 patients were initially diagnosed with muscular dystrophy because of the long-term clinical course and lack of inflammation on biopsy; 5 were diagnosed with FSHD based on a winged scapula. However, the following features suggested an alternative diagnosis, leading to anti-SRP antibody measurement: (1) lack of family history, (2) lack of facial involvement and asymmetry, (3) prominent dysphagia, and (4) profuse spontaneous activities on needle electromyography. All patients showed improvement with immunomodulating therapy.Anti-SRP antibody measurement should be considered in patients diagnosed with FSHD if they present with diagnostic hallmarks of anti-SRP myopathy listed above, to avoid oversight of this potentially treatable disorder.

We report a patient with GNE myopathy with a homozygous mutation (c.1505-4G>A) in GNE gene. The patient recognized progressive weakness of extremities at age 60. Neurological examination at age 65 revealed severe weakness and atrophy in the tibialis anterior muscles and distal predominant moderate weakness in the extremities. Muscle biopsy performed at age 65 showed myopathic changes with rimmed vacuoles, and the noteworthy finding was non-caseating epithelioid cell granuloma formation surrounded by numerous inflammatory cells. Granuloma formation has never been reported in patients with GNE myopathy. We presume that aggregation of abnormal proteins and autophagy dysregulation in the myocytes of GNE myopathy could induce granuloma formation.

We report the case of a 15-year-old Japanese girl with myopathy associated with antibodies to a signal recognition particle (anti-SRP myopathy). The patient presented with progressive symmetrical proximal muscle weakness that caused difficulty in walking within 3 months, and marked elevation of the serum creatine kinase levels. A skeletal muscle biopsy revealed active necrotic and regenerating processes, with mild inflammatory changes. Based on the above findings, the patient was diagnosed as having anti-SRP myopathy. Only a limited number of pediatric patients with anti-SRP myopathy has been reported previously, with usually a poor prognosis. Early diagnosis is important for obtaining a better prognosis in patients with anti-SRP myopathy.

Background Glucosamine (UDP-N-acetyl)-2-epimerase/ N -acetylmannosamine kinase (GNE) myopathy, also called distal myopathy with rimmed vacuoles (DMRV) or hereditary inclusion body myopathy (HIBM), is a rare, progressive autosomal recessive disorder caused by mutations in the GNE gene. Here, we examined the relationship between genotype and clinical phenotype in participants with GNE myopathy. Methods Participants with GNE myopathy were asked to complete a questionnaire regarding medical history and current symptoms. Results A total of 71 participants with genetically confirmed GNE myopathy (27 males and 44 females; mean age, 43.1±13.0 (mean±SD) years) completed the questionnaire. Initial symptoms ( e.g. , foot drop and lower limb weakness) appeared at a mean age of 24.8±8.3years. Among the 71 participants, 11 (15.5%) had the ability to walk, with a median time to loss of ambulation of 17.0±2.1years after disease onset. Participants with a homozygous mutation (p.V572L) in the N -acetylmannosamine kinase domain (KD/KD participants) had an earlier disease onset compared to compound heterozygous participants with mutations in the uridine diphosphate-N-acetylglucosamine (UDP-GlcNAc) 2-epimerase and N -acetylmannosamine kinase domains (ED/KD participants; 26.3±7.3 vs. 21.2±11.1years, respectively). KD/KD participants were more frequently non-ambulatory compared to ED/KD participants at the time of survey (80% vs. 50%). Data were verified using medical records available from 17 outpatient participants. Conclusions Homozygous KD/KD participants exhibited a more severe phenotype compared to heterozygous ED/KD participants.

Background Missense mutations in dynamin 2 gene ( DNM2 ) are associated with autosomal dominant centronuclear myopathy (CNM) with characteristic histopathological findings of centrally located myonuclei in a large number of muscle fibers. Methods To identify Japanese CNM caused by DNM2 mutations (DNM2-CNM), we sequenced DNM2 in 22 unrelated Japanese patients who were pathologically diagnosed with CNM. The clinical and pathological findings of DNM2-CNM in patients were reviewed. Results We identified 3 different heterozygous missense mutations (p.E368K, p.R369W, and p.R465W) in 4 probands from 4 families. Clinically, calf muscle atrophy and pes cavus are features that are highly suggestive of DNM2-CNM among all CNMs. Pathologically, all 4 DNM2-CNM patients showed a radial distribution of myofibrils in scattered fibers, type 1 fiber atrophy, type 1 fiber predominance, and type 2C fibers. None of the non-DNM2-CNM patients exhibited all the 4 abovementioned pathological features, although some patients showed radial distribution without type 1 fiber atrophy and/or type 2C fibers. Discussion These results indicate that the clinicopathological features of DNM2-CNM are rather homogeneous and can be distinguished from the features of non-DNM2-CNM.

Objectives To investigate associations between signal transducer and activator of transcription 4 (STAT4), one of the most commonly acknowledged genes for the risk of multiple autoimmune diseases, with susceptibility to adult-onset polymyositis/dermatomyositis among Japanese individuals. Methods A single nucleotide polymorphism of STAT4, rs7574865, was genotyped using TaqMan assay in 1143 Japanese individuals. The first set comprised 138 polymyositis/dermatomyositis patients and 289 controls and the second set comprised 322 patients and 394 controls. 460 patients (273 polymyositis and 187 dermatomyositis patients) and 683 controls were genotyped. Results rs7574865T conferred a risk of polymyositis/dermatomyositis with an OR of 1.37 (95% CI 1.16 to 1.64; p=4x10 −4 ; p corr =0.0012). Both polymyositis and dermatomyositis exhibited high associations with the rs7574865T allele (polymyositis: OR=1.36, 95% CI 1.11 to 1.67; p=0.0039; p corr =0.012; dermatomyositis: OR=1.40, 95% CI 1.10 to 1.78; p=0.0054; p corr =0.016). The association between this STAT4 polymorphism and interstitial lung disease (ILD) was also investigated in the first set of polymyositis/dermatomyositis patients (n=138); those with ILD (n=79) bore rs7574865T more frequently compared with controls (OR 1.59, 95% CI 1.10 to 2.28; p=0.013; p corr =0.039). Conclusion This is the first study to show a positive association between a STAT4 polymorphism and polymyositis/dermatomyositis, suggesting that polymyositis/dermatomyositis shares a gene commonly associated with the risk of other autoimmune diseases.

Muscle glycogen storage disease 0 (GSD0) is caused by glycogen depletion in skeletal and cardiac muscles due to deficiency of glycogen synthase 1 (GYS1), which is encoded by the GYS1 gene. Only two families with this disease have been identified. We report a new muscle GSD0 patient, a Japanese girl, who had been suffering from recurrent attacks of exertional syncope accompanied by muscle weakness and pain since age 5 years until she died of cardiac arrest at age 12. Muscle biopsy at age 11 years showed glycogen depletion in all muscle fibers. Her loss of consciousness was gradual and lasted for hours, suggesting that the syncope may not be simply caused by cardiac event but probably also contributed by metabolic distress.

Distal myopathy with rimmed vacuoles/hereditary inclusion body myopathy (DMRV/hIBM), characterized by progressive muscle atrophy, weakness, and degeneration, is due to mutations in GNE, a gene encoding a bifunctional enzyme critical in sialic acid biosynthesis. In the DMRV/hIBM mouse model, which exhibits hyposialylation in various tissues in addition to muscle atrophy, weakness, and degeneration, we recently have demonstrated that the myopathic phenotype was prevented by oral administration of N-acetylneuraminic acid, N-acetylmannosamine, and sialyllactose, underscoring the crucial role of hyposialylation in the disease pathomechanism. The choice for the preferred molecule, however, was limited probably by the complex pharmacokinetics of sialic acids and the lack of biomarkers that could clearly show dose response. To address these issues, we screened several synthetic sugar compounds that could increase sialylation more remarkably and allow demonstration of measurable effects in the DMRV/hIBM mice. In this study, we found that tetra-O-acetylated N-acetylmannosamine increased cell sialylation most efficiently, and in vivo evaluation in DMRV/hIBM mice revealed a more dramatic, measurable effect and improvement in muscle phenotype, enabling us to establish analysis of protein biomarkers that can be used for assessing response to treatment. Our results provide a proof of concept in sialic acid-related molecular therapy with synthetic monosaccharides.

Facioscapulohumeral muscular dystrophy (FSHD) is a common autosomal dominant muscular dystrophy caused by truncation of D4Z4 repeat array on chromosome 4q35. Facial and shoulder-girdle muscles are preferentially affected but clinical symptoms are quite variable even within the same family. Asymmetrical muscle involvement is also characteristic in this disease. There are no disease specific changes on muscle pathology, and genetic diagnosis is performed by the southern blotting analysis. Recent advances provide us several ideas on possible pathomechanisms of this complicated disease. There are several genes on chromosome 4q35 region including DUX4 within D4Z4 repeats. Transcription of these genes is usually repressed by epigenetic modifications of this chromosomal region and also accumulation of transcriptional repressors to the repeat array. Shortening of the D4Z4 repeats observed in FSHD can cause structural changes of this chromosomal region, reduced recruitment of repressors, and expression of noncoding RNA which can enhance transcription of the genes on chromosome 4q35 region. Actually, increased mRNA expression levels of 4q35 genes was reported in FSHD cells, together with their undesirable roles on muscles by overexpression models. Further analysis is required to elucidate the precise pathomechanisms of FSHD.

Filamin C is an actin-crosslinking protein that is specifically expressed in cardiac and skeletal muscles. Although mutations in the filamin C gene cause human myopathy with cardiac involvement, the function of filamin C in vivo is not yet fully understood. Here we report a medaka mutant, zacro (zac), that displayed an enlarged heart, caused by rupture of the myocardiac wall, and progressive skeletal muscle degeneration in late embryonic stages. We identified zac to be a homozygous nonsense mutation in the filamin C (flnc) gene. The medaka filamin C protein was found to be localized at myotendinous junctions, sarcolemma, and Z-disks in skeletal muscle, and at intercalated disks in the heart. zac embryos showed prominent myofibrillar degeneration at myotendinous junctions, detachment of myofibrils from sarcolemma and intercalated disks, and focal Z-disk destruction. Importantly, the expression of γ-actin, which we observed to have a strong subcellular localization at myotendinous junctions, was specifically reduced in zac mutant myotomes. Inhibition of muscle contraction by anesthesia alleviated muscle degeneration in the zac mutant. These results suggest that filamin C plays an indispensable role in the maintenance of the structural integrity of cardiac and skeletal muscles for support against mechanical stress.

Objective: To determine the genetic variants in patients with dystroglycanopathy (DGP) and assess the pathogenicity of these variants. Methods: A total of 20 patients with DGP were identified by immunohistochemistry or Western blot analysis. Whole-exome sequencing (WES) was performed using patient samples. The pathogenicity of the variants identified was evaluated on the basis of the phenotypic recovery in a knockout (KO) haploid human cell line by transfection with mutated POMGNT2 cDNA and on the basis of the in vitro enzymatic activity of mutated proteins. Results: WES identified homozygous and compound heterozygous missense variants in POMGNT2 in 3 patients with the milder limb-girdle muscular dystrophy (LGMD) and intellectual disability without brain malformation. The 2 identified variants were located in the putative glycosyltransferase domain of POMGNT2, which affected its enzymatic activity. Mutated POMGNT2 cDNAs failed to rescue the phenotype of POMGNT2 -KO cells. Conclusions: Novel variants in POMGNT2 are associated with milder forms of LGMD. The findings of this study expand the clinical and pathologic spectrum of DGP associated with POMGNT2 variants from the severest Walker-Warburg syndrome to the mildest LGMD phenotypes. The simple method to verify pathogenesis of variants may allow researchers to evaluate any variants present in all of the known causative genes and the variants in novel candidate genes to detect DGPs, particularly without using patients9 specimens.

Congenital muscular dystrophy is a heterogeneous group of inherited muscle diseases characterized clinically by muscle weakness and hypotonia in early infancy. A number of genes harboring causative mutations have been identified, but several cases of congenital muscular dystrophy remain molecularly unresolved. We examined 15 individuals with a congenital muscular dystrophy characterized by early-onset muscle wasting, mental retardation, and peculiar enlarged mitochondria that are prevalent toward the periphery of the fibers but are sparse in the center on muscle biopsy, and we have identified homozygous or compound heterozygous mutations in the gene encoding choline kinase beta (CHKB). This is the first enzymatic step in a biosynthetic pathway for phosphatidylcholine, the most abundant phospholipid in eukaryotes. In muscle of three affected individuals with nonsense mutations, choline kinase activities were undetectable, and phosphatidylcholine levels were decreased. We identified the human disease caused by disruption of a phospholipid de novo biosynthetic pathway, demonstrating the pivotal role of phosphatidylcholine in muscle and brain.

Objective: Emery-Dreifuss muscular dystrophy (EDMD) is a genetically heterogeneous muscular disease that presents with muscular dystrophy, joint contractures, and cardiomyopathy with conduction defects. Mutations in several nuclear envelope protein genes have been associated with EDMD in less than half of patients, implying the existence of other causative and modifier genes. We therefore analyzed TMEM43, which encodes LUMA, a newly identified nuclear membrane protein and also a binding partner of emerin and lamins, to investigate whether LUMA may contribute to the pathomechanism of EDMD-related myopathy. Methods: Forty-one patients with EDMD-related myopathy were enrolled. In vitro and in vivo transfection analyses were performed to assay the binding partners and oligomerization of mutant LUMA. Results: We identified heterozygous missense mutations, p.Glu85Lys and p.Ile91Val in TMEM43, in 2 EDMD-related myopathy patients. Reduced nuclear staining of LUMA was observed in the muscle from the patient with p.Glu85Lys mutation. By in vitro transfection analysis, p.Glu85Lys mutant LUMA resulted to failure in oligomerization, a process that may be important for protein complex formation on nuclear membrane. Furthermore, we demonstrated for the first time that LUMA can interact with another nuclear membrane protein, SUN2, in addition to emerin. Cells expressing mutant LUMA revealed reduced nuclear staining with or without aggregates of emerin and SUN2 together with a higher proportion of abnormally shaped nuclei. In vivo expression of mutant LUMA by electroporation in mouse tibialis anterior muscles likewise demonstrated the decreased staining of emerin and SUN2 on myonuclei. Interpretation: Our results suggest that mutant LUMAs may be associated with EDMD-related myopathy. ANN NEUROL 2011;69:1005–1013

Thepatientwasa14-year-oldThaiboywhopresentedatanorthopedic clinic with kyphoscoliosis first detected 1 yearprior to medical attention. He was the first child of non-consanguineous parents; the pregnancy and delivery wereuneventful.He had normal developmental milestones.Thepatient noticed easy fatigability after exercise which wors-ened during the past year. His younger brother was 10years old and healthy. There was no history ofneuromuscular disease in his family. His father passedaway due to an unrelated incident. General examinationrevealed a body weight of 30 kg and a height of 149 cm,bilateral ptosis, high-arched palate, kyphoscoliosis, andasymmetrical chest wall. Proximal muscle weakness ofgrade 4 by Medical Research Council Scale in all extrem-itiesandareflexiawerenoted.Themuscletonewasnormal.SerumCKwas49 IU/L.Echocardiogramshowedmildpul-monary and tricuspid regurgitation. Pulmonary functiontestsshowedrestrictivelungdisease;theforcedvitalcapac-ity was 1.56 L (51% of predicted). Sleep study revealedapnea-hypopnea index 13.6 per hour associated withsevere oxygen desaturation (minimum SpO

Utrophin is a widely expressed paralogue of dystrophin, the protein responsible for Duchenne muscular dystrophy. Utrophin is a large spectrin-like protein whose C-terminal domain mediates anchorage to a laminin receptor, dystroglycan (DG). The rod domain, composed of 22 spectrin-like repeats, connects the N-terminal actin-binding domain and the C-terminal DG binding domain, and thus mediates molecular linkage between intracellular F-actin and extracellular basement membrane. Previously, we demonstrated that a cell polarity-regulating kinase, PAR-1b, interacts with the utrophin-DG complex, and positively regulates the interaction between utrophin and DG. In this study, we demonstrate that the 8th and 9th spectrin-like repeats (R8 and R9) of utrophin cooperatively form a PAR-1b-interacting domain, and that Ser1258 within R9 is specifically phosphorylated by PAR-1b. Substitution of Ser1258 to alanine reduces the interaction between utrophin and DG, suggesting that the Ser1258 phosphorylation contributes to the stabilization of the utrophin-DG complex. Interestingly, PAR-1b also binds and phosphorylates R8-9 of dystrophin, and colocalizes with dystrophin at the skeletal muscle membrane. These results reveal a novel function of the rod domain of utrophin beyond that of a passive structural linker connecting the N- and C-terminal domain.

The lack of a small-animal model has hampered the analysis of hepatitis C virus (HCV) pathogenesis. The tupaia ( Tupaia belangeri ), a tree shrew, has shown susceptibility to HCV infection and has been considered a possible candidate for a small experimental model of HCV infection. However, a longitudinal analysis of HCV-infected tupaias has yet to be described. Here, we provide an analysis of HCV pathogenesis during the course of infection in tupaias over a 3-year period. The animals were inoculated with hepatitis C patient serum HCR6 or viral particles reconstituted from full-length cDNA. In either case, inoculation caused mild hepatitis and intermittent viremia during the acute phase of infection. Histological analysis of infected livers revealed that HCV caused chronic hepatitis that worsened in a time-dependent manner. Liver steatosis, cirrhotic nodules, and accompanying tumorigenesis were also detected. To examine whether infectious virus particles were produced in tupaia livers, naive animals were inoculated with sera from HCV-infected tupaias, which had been confirmed positive for HCV RNA. As a result, the recipient animals also displayed mild hepatitis and intermittent viremia. Quasispecies were also observed in the NS5A region, signaling phylogenic lineage from the original inoculating sequence. Taken together, these data suggest that the tupaia is a practical animal model for experimental studies of HCV infection.

We report a patient harboring a novel homozygous mutation of c.604T > G (p.F202V) in POMT2 . He showed delayed psychomotor development but acquired the ability to walk at the age of 3 years and 10 months. His brain MRI was normal. No ocular abnormalities were seen. Biopsied skeletal muscle revealed markedly decreased but still detectable glycosylated forms of alpha-dystroglycan (α-DG). Our results indicate that mutations in POMT2 can cause a wide spectrum of clinical phenotypes as observed in other genes associated with α-dystroglycanopathy. Presence of small amounts of partly glycosylated α-DG may have a role in reducing the clinical symptoms of α-dystroglycanopathy.

Causative genes have been identified only in four types oflipid storage myopathies (LSMs): SLC22A5 for primary carnitine deficiency(PCD); ETFA , ETFB , and ETFDH for multiple acyl-coenzyme A dehydroge-nation deficiency (MADD); PNPLA2 for neutral lipid storage disease withmyopathy (NLSDM); and ABHD5 for neutral lipid storage disease withichthyosis. However, the frequency of these LSMs has not been determined.We found mutations in only 9 of 37 LSM patients (24%): 3 in SLC22A5 ;4inMADD-associated genes; and 2 in PNPLA2 . This low frequency suggeststhe existence of other causative genes . Muscle coenzyme Q 10 levels werenormal or only mildly reduced in two MADD patients, indicating that ETFDHmutations may not always be associated with CoQ 10 deficiency. The 2patients with PNPLA2 mutations had progressive, non-episodic muscledisease with rimmed vacuoles. This suggests there is a different patho-mechanism from other LSMs. Muscle Nerve 39: 333–342, 2009 CLINICAL AND GENETIC ANALYSISOF LIPID STORAGE MYOPATHIES

Multiple acyl-CoA dehydrogenase deficiency (MADD) is a metabolic disorder due to dysfunction of electron transfer flavoprotein (ETF) or ETF-ubiquinone oxidoreductase (ETF-QO). Mutations in ETFDH, encoding ETF-QO have been associated with both riboflavin-responsive and non-responsive MADD as well as a myopathic form of CoQ(10) deficiency, although pathomechanisms responsible for these different phenotypes are not well-defined. We performed mutation analysis in four Taiwanese MADD patients. Three novel ETFDH mutations were identified in four patients and all harbored the p.A84T mutation. Muscle CoQ(10) levels and respiratory chain activities measured in two patients were normal. Three patients improved on riboflavin together with carnitine. Our results show that not all MADD patients have CoQ(10) deficiency. Based upon our data, riboflavin and carnitine may be the first-line treatment for MADD.

Background Mutations in FKTN encoding for fukutin cause Fukuyama-type congenital muscular dystrophy characterized by severe muscle wasting and hypotonia with mental retardation. Fukuyama-type congenital muscular dystrophy is a recessive genetic trait. FKTN mutations in patients with dilated cardiomyopathy (DCM) have been investigated by our research group. The patients showed hyper-CKemia with mild or no muscle weakness and without mental retardation, suggesting that the clinical spectrum of FKTN mutations are wider than previously thought. The current study was designed to further explore the association of FKTN mutations with DCM or hypertrophic cardiomyopathy (HCM). Methods and Results A total of 172 patients with DCM, 144 patients with familial HCM and 384 control individuals were analyzed for FKTN mutations. There was a DCM patient who was a compound heterozygote of a 3-kb insertion mutation and a missense mutation Cys101Phe. The patient showed hyper-CKemia with mild muscle involvement and no brain involvement. In contrast, 2 other DCM patients and 3 controls were heterozygous for the insertion mutation and normal allele, showing that the heterozygous insertion mutation itself was not associated with DCM. No mutation was found in the HCM patients. Conclusions These observations indicated that the compound heterozygous FKTN mutation was a rare cause of DCM. Hyper-CKemia might be indicative of FKTN mutation in DCM. (Circ J 2009; 73: 158 – 161)

Distal myopathy with rimmed vacuoles (DMRV), also called hereditary inclusion body myopathy (hIBM), is characterized clinically by weakness and atrophy that initially involves the distal muscles and pathologically by the presence of rimmed vacuoles (RVs) or intracellular protein deposits in myofibers. It is caused by mutations in the UDP- N-acetylglucosamine 2-epimerase/ N-acetylmannosamine kinase ( GNE) gene that is important in sialic acid synthesis. Recently, we generated a mouse model ( Gne−/−h GNED176VTg) that exhibits muscle weakness and pathological changes similar to DMRV patients. To gain better understanding of the pathomechanism of DMRV, we determined temporal changes in the overall motor performance of this model mouse for DMRV in correlation with the structure and function of isolated skeletal muscles and muscle pathology. These DMRV mice exhibited muscle weakness, decreased whole muscle mass and cross-sectional area (CSA), and reduced contractile power in an age-related manner. Single-fiber CSA further supported the finding of muscle atrophy that involved both type I and type II fibers. These results suggest that atrophy is highly correlated with reduced production of force at young age, both in vivo and ex vivo, thereby implicating the important role of atrophy in the pathomechanism of DMRV. In older age, and particularly in gastrocnemius muscles, RVs and intracellular inclusions were seen in type IIA fibers, further aggravating reduction of force and specific increase in twitch-tetanus ratio.

Distal myopathy is a group of heterogeneous disorders affecting predominantly distal muscles usually appearing from young to late adulthood with very rare cardiac complications. We report a 27-year-old man characterized clinically by distal myopathy and dilated cardiomyopathy, pathologically by lipid storage, and genetically by a PNPLA2 mutation. The patient developed weakness in his lower legs and fingers at age 20 years. Physical examination at age 27 years revealed muscle weakness and atrophy predominantly in lower legs and hands, and severe dilated cardiomyopathy. The patient had a homozygous four-base duplication (c.475_478dupCTCC) in exon 4 of PNPLA2.

SHPS-1 is an immunoglobulin superfamily protein with four immunoreceptor tyrosine-based inhibitory motifs (ITIMs) in its cytoplasmic region. Various neurotrophic factors induce the tyrosine phosphorylation of SHPS-1 and the association of SHPS-1 with the protein tyrosine phosphatase SHP-2. Using a yeast two-hybrid screen, we identified a protein tyrosine kinase, Csk-homologous kinase (CHK), as an SHPS-1-interacting protein. Immunoprecipitation and pull-down assays using glutathione S-transferase (GST) fusion proteins containing the Src homology 2 (SH2) domain of CHK revealed that CHK associates with tyrosine-phosphorylated SHPS-1 via its SH2 domain. HIS3 assay in a yeast two-hybrid system using the tyrosine-to-phenylalanine mutants of SHPS-1 indicated that the first and second ITIMs of SHPS-1 are required to bind CHK. Over-expression of wild-type CHK, but not a kinase-inactive CHK mutant, enhanced the phosphorylation of SHPS-1 and its subsequent association with SHP-2. CHK phosphorylated each of four tyrosines in the cytoplasmic region of SHPS-1 in vitro. Co-expression of SHPS-1 and CHK enhanced neurite outgrowth in PC12 cells. Thus, CHK phosphorylates and associates with SHPS-1 and is involved in neural differentiation via SHP-2 activation.

Objectives: To determine the frequency of primary collagen VI deficiency in congenital muscular dystrophy (CMD) in Japan and to establish the genotype-phenotype correlation. Methods: We performed immunohistochemistry for collagen VI in muscles from 362 Japanese patients with CMD, and directly sequenced the three collagen VI genes, COL6A1 , COL6A2 , and COL6A3 , in patients found to have collagen VI deficiency. Results: In Japan, primary collagen VI deficiency accounts for 7.2% of congenital muscular deficiency. Among these patients, five had complete deficiency (CD) and 29 had sarcolemma-specific collagen VI deficiency (SSCD). We found two homozygous and three compound heterozygous mutations in COL6A2 and COL6A3 in all five patients with CD, and identified heterozygous missense mutations or in-frame small deletions in 21 patients with SSCD in the triple helical domain (THD) of COL6A1 , COL6A2 , and COL6A3 . All mutations in SSCD were sporadic dominant. No genotype-phenotype correlation was seen. Conclusion: Primary collagen VI deficiency is the second most common CMD after Fukuyama type CMD in Japan. Dominant mutations located in the N-terminal side from the cysteine residue in the THD of COL6A1, COL6A2 , and COL6A3 are closely associated with SSCD.

Limb-girdle muscular dystrophy (LGMD) is a group of hereditary muscle diseases with preferential involvement of the shoulder and pelvic girdle muscles, but with no pathognomonic features as in facioscapulohumeral and congenital muscular dystrophies. We report 18-year-old female with progressive shoulder and pelvic muscle weakness. She had marked restrictive pulmonary dysfunction. Echocardiogram showed mild decrease in ejection fraction of 52% (normal: >55%). She was first seen in our hospital at age 2 years with progressive proximal muscle weakness and elevated creatine kinase (CK) level to 15,290 IU/L, with what clinically and pathologically appeared to be steroid-responsive inflammatory myopathy. She responded dramatically to steroid therapy. Progressive proximal muscle weakness began again at age 8 years. Serum CK was 14,910 IU/L. She was wheelchair-bound by age 12. Muscle biopsy showed dystrophic changes without inflammation with reduced immunoreactivity to an antibody against sugar chain (VIA4-1) of alpha-dystroglycan. On laminin overlay assay, there was a nearly complete loss of laminin-binding activity to alpha-dystroglycan. Genetic analysis of fukutin-related protein (FKRP) gene revealed a novel compound heterozygous mutation of c.823C>T (p.R275C) and c.948delC, confirming the diagnosis of LGMD2I, the first reported case in East Asia.

Reducing body myopathy (RBM) is a rare pathologically defined myopathy characterized by the presence of inclusion bodies which are abnormally stained by menadione–nitroblue–tetrazolium. The clinical symptoms vary widely as to the age of onset, disease progression and severity. Among the many reported patients, there have been only three families with this disorder, showing a manifold of clinicopathological features in each family. We report a fourth family with RBM affecting a boy and his mother. The proband (boy) began to have difficulty putting on his trousers at age 10 years and difficulty arising from a chair at 11 years. His spine was rigid. His mother, on the other hand, noticed foot-drop at the age 29, but the clinical course was rapidly progressive, and she was wheelchair-bound at 34 years. Both patients had generalized muscle weakness and atrophy and with mild CK elevation. Muscle pathology was characterized by the presence of atrophic fibers with reducing bodies in some areas. As these patients demonstrate, clinical symptoms in RBM are very variable, even within the same family. There are no specific clinical characteristics distinctive to RBM, thus further studies are necessary to characterize this disorder both clinically and pathologically.

Facioscapulohumeral muscular dystrophy 2 (FSHD2) is a genetic muscular disorder characterized by DNA hypomethylation on the 4q-subtelomeric macrosatellite repeat array, D4Z4. FSHD2 is caused by heterozygous mutations in the gene encoding structural maintenance of chromosomes flexible hinge domain containing 1 (SMCHD1). Because there has been no study on FSHD2 in Asian populations, it is not known whether this disease mechanism is widely seen. To identify FSHD2 patients with SMCHD1 mutations in the Japanese population, bisulfite pyrosequencing was used to measure DNA methylation on the D4Z4 repeat array, and in patients with DNA hypomethylation, the SMCHD1 gene was sequenced by the Sanger method. Twenty patients with D4Z4 hypomethylation were identified. Of these, 13 patients from 11 unrelated families had ten novel and one reported SMCHD1 mutations: four splice-site, two nonsense, two in-frame deletion, two out-of-frame deletion, and one missense mutations. One of the splice-site mutations was homozygous in the single patient identified with this. In summary, we identified novel SMCHD1 mutations in a Japanese cohort of FSHD2 patients, confirming the presence of this disease in a wider population than previously known.

We retrospectively reviewed respiratory and cardiac function in patients with dysferlinopathy, including 2 autopsy cases with respiratory dysfunction.Subjects included 48 patients who underwent respiratory evaluation (n = 47), electrocardiography (n = 46), and echocardiography (n = 23).Of the 47 patients, 10 had reduced percent forced vital capacity (%FVC), and 4 required non-invasive positive pressure ventilation. %FVC was significantly correlated with disease duration, and mean %FVC was significantly lower in non-ambulatory patients, as well as in those aged ≥65 years with normal creatine kinase levels. On electrocardiography, QRS complex duration was prolonged in 19 patients, although no significant association with age, disease duration, or respiratory function was found. Echocardiography indicated no left ventricular dysfunction in any patient. Histopathology of autopsied cases revealed mild cardiomyopathy and moderate diaphragm involvement.Patients with dysferlinopathy may develop severe respiratory failure and latent cardiac dysfunction. Both respiratory and cardiac function should be monitored diligently.

Objective: To clarify whether there is any association between inclusion body myositis (IBM) and hepatitis C virus (HCV) infection. Methods: We assessed the prevalence of HCV infection in 114 patients with IBM whose muscle biopsies were analyzed pathologically for diagnostic purpose from 2002 to 2012 and in 44 age-matched patients with polymyositis diagnosed in the same period as a control by administering a questionnaire survey to the physicians in charge. We also compared clinicopathologic features including the duration from onset to development of representative symptoms of IBM and the extent of representative pathologic changes between patients with IBM with and without HCV infection. Results: A significantly higher number of patients with IBM (28%) had anti-HCV antibodies as compared with patients with polymyositis (4.5%; odds ratio 8.2, 95% confidence interval 1.9–36) and the general Japanese population in their 60s (3.4%). Furthermore, between patients with IBM with and without HCV infection, we did not find any significant difference in the clinicopathologic features, indicating that the 2 groups have essentially the same disease regardless of HCV infection. Conclusion: Our results provide the statistical evidence for an association between IBM and HCV infection, suggesting a possible pathomechanistic link between the 2 conditions.

Background: Dysferlin is a sarcolemmal protein that is defective in Miyoshi myopathy and limb-girdle muscular dystrophy type 2B, and is involved in sarcolemmal repair. Primary cultured myoblasts and myotubes established from patient muscle biopsies have been widely utilized to explore the molecular mechanism of dysferlinopathy. Objectives: The purpose of this study was to explore the possible utility of dermal fibroblasts from dysferlin-deficient patients and SJL mice as a tool for studying dysferlinopathy. Methods: Dysferlin protein expression in fibroblasts from dysferlin-deficient patients and SJL mice was analyzed by immunoblotting and immunocytochemistry. The membrane wound-repair assay was performed on the fibroblasts using a confocal microscope equipped with a UV-laser. The membrane blebbing assay using hypotonic shock, in which normal membrane blebbing is detected only in the presence of dysferlin, was also performed using human and mouse fibroblasts. Results: Mis-sense mutated dysferlin was expressed at a very low level in fibroblasts from a dysferlinopathy patient, and lower expression level of truncated dysferlin was observed in SJL mouse fibroblast. Fibroblasts from patients with dysferlinopathy and SJL mice showed attenuated membrane repair and did not form membrane blebs in response to hypoosmotic shock. Proteosomal inhibitior increased mis-sense mutated or truncated dysferlin levels, and restored membrane blebbing, however, proteosomal inhibition failed to improve levels of dysferlin with non-sense or frame-shift mutation. Conclusion: Fibroblasts from dysferlinopathy patients and SJL mice showed attenuated plasma membrane repair, and could be a tool for studying dysferlinopathy. Abstract Background: Dysferlin is a sarcolemmal protein that is defective in Miyoshi myopathy and limb-girdle muscular dystrophy type 2B, and is involved in sarcolemmal repair. Primary cultured myoblasts and myotubes established from patient muscle biopsies have been widely utilized to explore the molecular mechanism of dysferlinopathy. Objectives: The purpose of this study was to explore the possible utility of dermal fibroblasts from dysferlin-deficient patients and SJL mice as a tool for studying dysferlinopathy. Methods: Dysferlin protein expression in fibroblasts from dysferlin-deficient patients and SJL mice was analyzed by immunoblotting and immunocytochemistry. The membrane wound-repair assay was performed on the fibroblasts using a confocal microscope equipped with a UV-laser. The membrane blebbing assay using hypotonic shock, in which normal membrane blebbing is detected only in the presence of dysferlin, was also performed using human and mouse fibroblasts. Results: Mis-sense mutated dysferlin was expressed at a very low level in fibroblasts from a dysferlinopathy patient, and lower expression level of truncated dysferlin was observed in SJL mouse fibroblast. Fibroblasts from patients with dysferlinopathy and SJL mice showed attenuated membrane repair and did not form membrane blebs in response to hypoosmotic shock. Proteosomal inhibitior increased mis-sense mutated or truncated dysferlin levels, and restored membrane blebbing, however, proteosomal inhibition failed to improve levels of dysferlin with non-sense or frame-shift mutation. Conclusion: Fibroblasts from dysferlinopathy patients and SJL mice showed attenuated plasma membrane repair, and could be a tool for studying dysferlinopathy. Abstract Background: Dysferlin is a sarcolemmal protein that is defective in Miyoshi myopathy and limb-girdle muscular dystrophy type 2B, and is involved in sarcolemmal repair. Primary cultured myoblasts and myotubes established from patient muscle biopsies have been widely utilized to explore the molecular mechanism of dysferlinopathy. Objectives: The purpose of this study was to explore the possible utility of dermal fibroblasts from dysferlin-deficient patients and SJL mice as a tool for studying dysferlinopathy. Methods: Dysferlin protein expression in fibroblasts from dysferlin-deficient patients and SJL mice was analyzed by immunoblotting and immunocytochemistry. The membrane wound-repair assay was performed on the fibroblasts using a confocal microscope equipped with a UV-laser. The membrane blebbing assay using hypotonic shock, in which normal membrane blebbing is detected only in the presence of dysferlin, was also performed using human and mouse fibroblasts. Results: Mis-sense mutated dysferlin was expressed at a very low level in fibroblasts from a dysferlinopathy patient, and lower expression level of truncated dysferlin was observed in SJL mouse fibroblast. Fibroblasts from patients with dysferlinopathy and SJL mice showed attenuated membrane repair and did not form membrane blebs in response to hypoosmotic shock. Proteosomal inhibitior increased mis-sense mutated or truncated dysferlin levels, and restored membrane blebbing, however, proteosomal inhibition failed to improve levels of dysferlin with non-sense or frame-shift mutation. Conclusion: Fibroblasts from dysferlinopathy patients and SJL mice showed attenuated plasma membrane repair, and could be a tool for studying dysferlinopathy.

Serine palmitoyltransferase (SPT) is a first-step enzyme in the sphingolipid biosynthetic pathway. Myriocin is an inhibitor of SPT and suppresses replication of the hepatitis C virus (HCV) replicon. However, it is still unknown whether this SPT inhibitor suppresses HCV replication in vivo. We investigated the anti-HCV effect of myriocin against intact HCV using chimeric mice with humanized liver infected with HCV genotype 1a or 1b. We administered myriocin into HCV infected chimeric mice and succeeded in reducing the HCV RNA levels in serum and liver to 1/10–1/100 of the levels prior to the 8 day treatment. Furthermore, combined treatment with pegylated interferon reduced the HCV RNA levels to less than 1/1000 of the control levels. We strongly suggest that suppression of SPT reduces HCV replication, and therefore that the SPT inhibitor is potentially a novel drug in the treatment of HCV infection.

Ryanodine receptor 1 ( RYR1 ) gene mutations are associated with central core disease (CCD), multiminicore disease (MmD) and malignant hyperthermia (MH), and have been reported to be responsible for 47–67% of patients with CCD and rare cases with MmD. However, to date, the true frequency and distribution of the mutations along the RYR1 gene have not been determined yet, since mutation screening has been limited to three ‘hot spots’, with particular attention to the C-terminal region. In this study, 27 unrelated Japanese CCD patients were included. Clinical histories and muscle biopsies were carefully reviewed. We sequenced all the 106 exons encoding RYR1 with their flanking exon–intron boundaries, and identified 20 novel and 3 previously reported heterozygous missense mutations in 25 of the 27 CCD patients (93%), which is a much higher mutation detection rate than that perceived previously. Among them, six were located outside the known ‘hot spots’. Sixteen of 27 (59%) CCD patients had mutations in the C-terminal ‘hot spot’. Three CCD patients had a probable autosomal recessive disease with two heterozygous mutations. Patients with C-terminal mutations had earlier onset and rather consistent muscle pathology characterized by the presence of distinct cores in almost all type 1 fibres, interstitial fibrosis and type 2 fibre deficiency. In contrast, patients with mutations outside the C-terminal region had milder clinical phenotype and harbour more atypical cores in their muscle fibres. We also sequenced two genes encoding RYR1-associated proteins as candidate causative genes for CCD: the 12 kD FK506-binding protein ( FKBP12 ) and the α1 subunit of L-type voltage-dependent calcium channel or dihydropyridine receptor ( CACNA1S ). However, no mutation was found, suggesting that these genes may not, or only rarely, be responsible for CCD. Our results indicate that CCD may be caused by RYR1 mutations in the majority of patients.

Facioscapulohumeral muscular dystrophy (FSHD) is a common muscular disorder, but clinical and genetic complications make its diagnosis difficult. Southern blot analysis detects a smaller sized EcoRI fragment on chromosome 4q35 in most facioscapulohumeral muscular dystrophy patients, that contains integral number of 3.3-kb tandem repeats known as D4Z4. The problems for the genetic diagnosis are that southern blotting for facioscapulohumeral muscular dystrophy is quite laborious and time-consuming, and the D4Z4 number is only estimated from the size of the fragment. We developed a more simplified diagnostic method using a long polymerase chain reaction (PCR) amplification technique. Successful amplification was achieved in all facioscapulohumeral muscular dystrophy patients with an EcoRI fragment size ranging from 10 to 25 kb, and each patient had a specific polymerase chain reaction product which corresponded to the size calculated from the number of D4Z4. Using southern blot analysis, more than 90% of facioscapulohumeral muscular dystrophy patients have a smaller EcoRI fragment than 26 kb in our series, and the number of D4Z4 repeats is precisely counted by this polymerase chain reaction method. We conclude that this long polymerase chain reaction method can be used as an accurate genetic screening technique for facioscapulohumeral muscular dystrophy patients.

Distal myopathy with rimmed vacuoles (DMRV) is an early-adult-onset, distal myopathy caused by a mutation of the UDP-N-acetylglucosamine 2 epimerase/N-acetylmannosamine kinase (GNE) gene. We herein report four Thai patients with DMRV who carried compound heterozygous mutations of the GNE gene including three novel (p.G89R, p.P511T, and p.I656N) and two known mutations (p.A524V and p.V696M). All patients shared p.V696M in one allele. Our study demonstrates the mutation spectrum of the GNE gene in Thai patients with DMRV.

Objectives: To identify gene mutations in patients with dystroglycanopathy and prove pathogenicity of those mutations using an in vitro cell assay. Methods: We performed whole-exome sequencing on 20 patients, who were previously diagnosed with dystroglycanopathy by immunohistochemistry and/or Western blot analysis. We also evaluated pathogenicity of identified mutations for phenotypic recovery in a DAG1 -knockout haploid human cell line transfected with mutated DAG1 complementary DNA. Results: Using exome sequencing, we identified compound heterozygous missense mutations in DAG1 in a patient with asymptomatic hyperCKemia and pathologically mild muscular dystrophy. Both mutations were in the N-terminal region of α-dystroglycan and affected its glycosylation. Mutated DAG1 complementary DNAs failed to rescue the phenotype in DAG1 -knockout cells, suggesting that these are pathogenic mutations. Conclusion: Novel mutations in DAG1 are associated with asymptomatic hyperCKemia with hypoglycosylation of α-dystroglycan. The combination of exome sequencing and a phenotype-rescue experiment on a gene-knockout haploid cell line represents a powerful tool for evaluation of these pathogenic mutations.

Dysferlinopathy and rigid spine syndrome occurring in a 50-year-old man is reported. The patient noticed stiffness of knee and ankle joints, which gradually extended to neck, wrist and elbow joints leading to difficulty in anterior flexion. Muscular weakness and wasting of the lower extremities had developed since age 40, accompanied by a limitation of anterior bending of the spine. Elevated serum CK was noticed. Muscle CT revealed atrophy with moderate fatty replacement of muscles in the neck, shoulder and pelvic girdle, and marked replacement in the para-vertebral muscles, posterior compartment of hamstrings and calf muscles. Electromyography showed a typical myogenic pattern, and muscle biopsy disclosed dystrophic changes, compatible with limb-girdle muscular dystrophy 2B. Loss of dysferlin expression was verified by immunohistochemistry, which was confirmed by a mini-multiplex Western blotting system. Gene analyses of the dysferlin gene disclosed compound heterozygotes for frameshift (G3016 + 1A) and a missense mutation (G3370T). This study might propose some clues to resolve the combination of musular dystrophies and rigid spine syndrome.

Mutations in the dysferlin gene (DYSF) on chromosome 2p13 cause distinct phenotypes of muscular dystrophy: limb-girdle muscular dystrophy type 2B (LGMD2B), Miyoshi myopathy (MM), and distal anterior compartment myopathy, which are known by the term 'dysferlinopathy'. We performed mutation analyses of DYSF in 14 Italian patients from 10 unrelated families with a deficiency of dysferlin protein below 20% of the value in normal controls by immunoblotting analysis. We identified 11 different mutations, including eight missense and three deletion mutations. Nine of them were novel mutations. We also identified a unique 6-bp insertion polymorphism within the coding region of DYSF in 15% of Italian population, which was not observed in East Asian populations. The correlation between clinical phenotype and the gene mutations was unclear, which suggested the role of additional genetic and epigenetic factors in modifying clinical symptoms.

Except for pancreaticobiliary maljunction, the relationship between a relatively long common channel and gallbladder carcinoma is unknown.For purposes of this study, a high confluence of pancreaticobiliary ducts was defined as a common channel that is 6 mm or greater in length, together with occlusion of the communication between the pancreatic and bile ducts during sphincter contraction. Pancreaticobiliary maljunction and high confluence of the pancreaticobiliary ducts were detected in 69 (2.1%) and 54 (1.6%), respectively, of 3300 consecutive patients who underwent ERCP. Proliferation activity and genetic alteration were examined in the non-carcinomatous epithelium of the gallbladder in patients with these two radiographic findings at ERCP.The Ki-67 labeling index in the epithelium in cases of a high confluence of the pancreaticobiliary ducts and pancreaticobiliary maljunction without biliary dilatation was significantly greater than that in cases of gallbladder carcinoma without these anomalies (p0.01). Overexpression of p53 and K-ras mutations were detected in, respectively, 22.2% and 27.8% of cases of a high confluence of pancreaticobiliary ducts.A relatively long common channel may be an important risk factor for the development of gallbladder carcinoma. Vigilance for the development of gallbladder carcinoma is indicated in patients with a relatively long common channel, in addition to those with pancreaticobiliary maljunction.