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1.
Neuropathology ; 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38922716

RESUMO

Glycogen storage diseases (GSDs) are a group of metabolic disorders affecting glycogen metabolism, with polyglucosan body myopathy type 1 (PGBM1) being a rare variant linked to RBCK1 gene mutations. Understanding the clinical diversity of PGBM1 aids in better characterization of the disease. Two unrelated Iranian families with individuals exhibiting progressive muscle weakness underwent clinical evaluations, genetic analysis using whole exome sequencing (WES), and histopathological examinations of muscle biopsies. In one case, a novel homozygous RBCK1 variant was identified, presenting with isolated myopathy without cardiac or immune involvement. Conversely, the second case harbored a known homozygous RBCK1 variant, displaying a broader phenotype encompassing myopathy, cardiomyopathy, inflammation, and immunodeficiency. Histopathological analyses confirmed characteristic skeletal muscle abnormalities consistent with PGBM1. Our study contributes to the expanding understanding of RBCK1-related diseases, illustrating the spectrum of phenotypic variability associated with distinct RBCK1 variants. These findings underscore the importance of genotype-phenotype correlations in elucidating disease mechanisms and guiding clinical management. Furthermore, the utility of next-generation sequencing techniques in diagnosing complex neurogenetic disorders is emphasized, facilitating precise diagnosis and enabling tailored genetic counseling for affected individuals and their families.

2.
BMC Musculoskelet Disord ; 25(1): 241, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539162

RESUMO

BACKGROUND: Limb girdle muscular dystrophies (LGMDs) constitute a heterogeneous group of neuromuscular disorders with a very variable clinical presentation and overlapping traits. The clinical symptoms of LGMD typically appear in adolescence or early adulthood. Genetic variation in the dysferlin gene (DYSF) has been associated with LGMD. METHODS: We characterized a recessive LGMD in a young adult from consanguineous Irani families using whole-exome sequencing (WES) technology. Sanger sequencing was performed to verify the identified variant. Computational modeling and protein-protein docking were used to investigate the impact of the variant on the structure and function of the DYSF protein. RESULTS: By WES, we identified a novel homozygous missense variant in DYSF (NM_003494.4: c.5876T > C: p. Leu1959Pro) previously been associated with LGMD phenotypes. CONCLUSIONS: The identification and validation of new pathogenic DYSF variant in the present study further highlight the importance of this gene in LGMD.


Assuntos
Distrofia Muscular do Cíngulo dos Membros , Adulto , Humanos , Adulto Jovem , Disferlina/genética , Distrofia Muscular do Cíngulo dos Membros/genética , Mutação , Mutação de Sentido Incorreto , Fenótipo
3.
J Magn Reson Imaging ; 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38031466

RESUMO

BACKGROUND: Glioma grading transformed in World Health Organization (WHO) 2021 CNS tumor classification, integrating molecular markers. However, the impact of this change on radiomics-based machine learning (ML) classifiers remains unexplored. PURPOSE: To assess the performance of ML in classifying glioma tumor grades based on various WHO criteria. STUDY TYPE: Retrospective. SUBJECTS: A neuropathologist regraded gliomas of 237 patients into WHO 2016 and 2021 from 2007 criteria. FIELD STRENGTH/SEQUENCE: Multicentric 0.5 to 3 Tesla; pre- and post-contrast T1-weighted, T2-weighted, and fluid-attenuated inversion recovery. ASSESSMENT: Radiomic features were selected using random forest-recursive feature elimination. The synthetic minority over-sampling technique (SMOTE) was implemented for data augmentation. Stratified 10-fold cross-validation with and without SMOTE was used to evaluate 11 classifiers for 3-grade (2, 3, and 4; WHO 2016 and 2021) and 2-grade (low and high grade; WHO 2007 and 2021) classification. Additionally, we developed the models on data randomly divided into training and test sets (mixed-data analysis), or data divided based on the centers (independent-data analysis). STATISTICAL TESTS: We assessed ML classifiers using sensitivity, specificity, accuracy, and the area under the receiver operating characteristic curve (AUC). Top performances were compared with a t-test and categorical data with the chi-square test using a significance level of P < 0.05. RESULTS: In the mixed-data analysis, Stacking Classifier without SMOTE achieved the highest accuracy (0.86) and AUC (0.92) in 3-grade WHO 2021 grouping. The results of WHO 2021 were significantly better than WHO 2016 (P-value<0.0001). In the 2-grade analysis, ML achieved 1.00 in all metrics. In the independent-data analysis, ML classifiers showed strong discrimination between grade 2 and 4, despite lower performance metrics than the mixed analysis. DATA CONCLUSION: ML algorithms performed better in glioma tumor grading based on WHO 2021 criteria. Nonetheless, the clinical use of ML classifiers needs further investigation. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

4.
Brain ; 145(2): 596-606, 2022 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-34515763

RESUMO

Sarcoglycanopathies include four subtypes of autosomal recessive limb-girdle muscular dystrophies (LGMDR3, LGMDR4, LGMDR5 and LGMDR6) that are caused, respectively, by mutations in the SGCA, SGCB, SGCG and SGCD genes. Delta-sarcoglycanopathy (LGMDR6) is the least frequent and is considered an ultra-rare disease. Our aim was to characterize the clinical and genetic spectrum of a large international cohort of LGMDR6 patients and to investigate whether or not genetic or protein expression data could predict a disease's severity. This is a retrospective study collecting demographic, genetic, clinical and histological data of patients with genetically confirmed LGMDR6 including protein expression data from muscle biopsies. We contacted 128 paediatric and adult neuromuscular units around the world that reviewed genetic data of patients with a clinical diagnosis of a neuromuscular disorder. We identified 30 patients with a confirmed diagnosis of LGMDR6 of which 23 patients were included in this study. Eighty-seven per cent of the patients had consanguineous parents. Ninety-one per cent of the patients were symptomatic at the time of the analysis. Proximal muscle weakness of the upper and lower limbs was the most common presenting symptom. Distal muscle weakness was observed early over the course of the disease in 56.5% of the patients. Cardiac involvement was reported in five patients (21.7%) and four patients (17.4%) required non-invasive ventilation. Sixty per cent of patients were wheelchair-bound since early teens (median age of 12.0 years). Patients with absent expression of the sarcoglycan complex on muscle biopsy had a significant earlier onset of symptoms and an earlier age of loss of ambulation compared to patients with residual protein expression. This study confirmed that delta-sarcoglycanopathy is an ultra-rare neuromuscular condition and described the clinical and molecular characteristics of the largest yet-reported collected cohort of patients. Our results showed that this is a very severe and quickly progressive disease characterized by generalized muscle weakness affecting predominantly proximal and distal muscles of the limbs. Similar to other forms of sarcoglycanopathies, the severity and rate of progressive weakness correlates inversely with the abundance of protein on muscle biopsy.


Assuntos
Distrofia Muscular do Cíngulo dos Membros , Distrofias Musculares , Sarcoglicanopatias , Adulto , Criança , Humanos , Debilidade Muscular , Distrofias Musculares/genética , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Distrofia Muscular do Cíngulo dos Membros/genética , Estudos Retrospectivos , Sarcoglicanopatias/genética , Sarcoglicanas/genética , Sarcoglicanas/metabolismo
5.
BMC Cardiovasc Disord ; 23(1): 487, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794383

RESUMO

BACKGROUND: The MYH7 gene, which encodes the slow/ß-cardiac myosin heavy chain, is mutated in myosin storage myopathy (MSM). The clinical spectrum of MSM is quite heterogeneous in that it ranges from cardiomyopathies to skeletal myopathies or a combination of both, depending on the affected region. In this study, we performed clinical and molecular examinations of the proband of an Iranian family with MSM in an autosomal dominant condition exhibiting proximal muscle weakness and dilated cardiomyopathy. METHODS: Following thorough clinical and paraclinical examinations, whole-exome sequencing `was performed on the proband (II-5). Pathogenicity prediction of the candidate variant was performed through in-silico analysis. Co-segregation analysis of the WES data among the family members was carried out by PCR-based Sanger sequencing. RESULTS: A novel heterozygous missense variant, MYH7 (NM_000257): c.C1888A: p.Pro630Thr, was found in the DNA of the proband and his children and confirmed by Sanger sequencing. The in-silico analysis revealed that p.Pro630Thr substitution was deleterious. The novel sequence variant fell within a highly conserved region of the head domain. Our findings expand the spectrum of MYH7 mutations. CONCLUSIONS: This finding could improve genetic counseling and prenatal diagnosis in families with clinical manifestations associated with MYH7-related myopathy.


Assuntos
Cardiomiopatia Dilatada , Doenças Musculares , Criança , Humanos , Músculo Esquelético , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/genética , Irã (Geográfico) , Mutação , Cadeias Pesadas de Miosina/genética , Linhagem , Miosinas Cardíacas/genética
6.
Hum Mol Genet ; 28(11): 1919-1929, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30715372

RESUMO

Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiovascular disorder, yet the genetic cause of up to 50% of cases remains unknown. Here, we show that mutations in KLHL24 cause HCM in humans. Using genome-wide linkage analysis and exome sequencing, we identified homozygous mutations in KLHL24 in two consanguineous families with HCM. Of the 11 young affected adults identified, 3 died suddenly and 1 had a cardiac transplant due to heart failure. KLHL24 is a member of the Kelch-like protein family, which acts as substrate-specific adaptors to Cullin E3 ubiquitin ligases. Endomyocardial and skeletal muscle biopsies from affected individuals of both families demonstrated characteristic alterations, including accumulation of desmin intermediate filaments. Knock-down of the zebrafish homologue klhl24a results in heart defects similar to that described for other HCM-linked genes providing additional support for KLHL24 as a HCM-associated gene. Our findings reveal a crucial role for KLHL24 in cardiac development and function.


Assuntos
Arritmias Cardíacas/genética , Cardiomiopatia Hipertrófica/mortalidade , Insuficiência Cardíaca/genética , Proteínas Repressoras/genética , Adulto , Animais , Arritmias Cardíacas/mortalidade , Arritmias Cardíacas/fisiopatologia , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/patologia , Morte Súbita Cardíaca/patologia , Desmina/genética , Modelos Animais de Doenças , Feminino , Ligação Genética/genética , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Homozigoto , Humanos , Masculino , Mutação , Linhagem , Fenótipo , Peixe-Zebra/genética
7.
J Neurogenet ; 35(2): 84-94, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33771085

RESUMO

Hereditary spastic paraplegia (HSP) is a clinically and genetically heterogeneous neurodegenerative disorder, characterized by lower-limb spasticity and weakness. To date, more than 82 loci/genes (SPG1-SPG82) have been identified that contribute to the cause of HSP. Despite the use of next-generation sequencing-based methods, genetic-analysis has failed in the finding of causative genes in more than 50% of HSP patients, indicating a more significant heterogeneity and absence of a given phenotype-genotype correlation. Here, we performed whole-exome sequencing (WES) to identify HSP-causing genes in three unrelated-Iranian probands. Candidate variants were detected and confirmed in the probands and co-segregated in the family members. The phenotypic data gathered and compared with earlier cases with the same sub-types of disease. Three novel homozygous variants, c.978delT; p.Q327Kfs*39, c.A1208G; p.D403G and c.3811delT; p.S1271Lfs*44, in known HSP-causing genes including ENTPD1, CYP7B1, and ZFYVE26 were identified, respectively. Intra and interfamilial clinical variability were observed among affected individuals. Mutations in CYP7B1 and ZFYVE26 are relatively common causes of HSP and associated with SPG5A and SPG15, respectively. However, mutations in ENTPD1 are related to SPG64 which is an ultra-rare form of HSP. The research affirmed more complexities of phenotypic manifestations and allelic heterogeneity in HSP. Due to these complexities, it is not feasible to show a clear phenotype-genotype correlation in HSP cases. Identification of more families with mutations in HSP-causing genes may help the establishment of this correlation, further understanding of the molecular basis of the disease, and would provide an opportunity for genetic-counseling in these families.


Assuntos
Apirase/genética , Proteínas de Transporte/genética , Família 7 do Citocromo P450/genética , Paraplegia Espástica Hereditária/genética , Esteroide Hidroxilases/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Mutação , Linhagem , Fenótipo , Paraplegia Espástica Hereditária/fisiopatologia , Sequenciamento do Exoma , Adulto Jovem
8.
J Emerg Med ; 61(6): e160-e163, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34518048

RESUMO

BACKGROUND: There are growing reports of the neurological involvement among patients with coronavirus disease 2019 (COVID-19). Headache, confusion, and anosmia after olfactory nerve disruption are the most prevalent presentation of the neurological involvement related to COVID-19. However, small numbers of the central nervous system involvement have been reported. CASE REPORT: A 49-year-old man was referred to our hospital with abrupt vision loss. Three weeks earlier he was admitted to the hospital based on his respiratory symptoms and was diagnosed with COVID-19 infection. Initial brain magnetic resonance imaging indicated diffuse restricted bilateral foci in both parietal and occipital lobes in favor of acute infarction. Diffuse weighted imaging demonstrated restricted bilateral hyperintense signals in parietal and occipital region. Occipital cortex biopsy showed brain tissue with focal infiltration of foamy macrophages mixed with reactive astrocytes and no plasma cell infiltration. Considering all of the evidence, post-COVID-19 encephalitis diagnosis was considered for the patient, and methyl prednisolone pulse therapy and intravenous immunoglobulin were initiated. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Although there are growing reports of neurological involvement among patients, blindness is rarely observed as a complication of post-COVID-19 encephalitis. To our knowledge, this is the first case of post-COVID-19 encephalitis that presented with bilateral vision loss primarily. This case may raise physicians' awareness of neurological complications of COVID-19.


Assuntos
COVID-19 , Doenças do Sistema Nervoso , Cegueira/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , SARS-CoV-2
9.
BMC Med Genet ; 21(1): 77, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32293312

RESUMO

BACKGROUND: Myopathy with extrapyramidal signs (MPXPS) is an autosomal recessive mitochondrial disorder which is caused by mutation in mitochondrial calcium uptake 1 (MICU1) gene located on chromosome 10q22.1. Next Generation Sequencing (NGS) technology is the most effective method for identification of pathogenic variants with the ability to overcome some limitations which Sanger sequencing may encountered. There are few reports on this rare disease around the world and here in this study we first revealed genetic identification of two affected individuals in an Iranian family with a novel mutation. CASE PRESENTATION: The proband was a 5-year-old girl from consanguenous parents. She was first clinically suspicious of affected with limb-girdle muscular dystrophy (LGMD). Muscle biopsy studies and autozygosity mapping, using four short tandem repeat (STR) markers linked to 6 genes of the most prevalent forms of LGMD, ruled out calpainopathy, dysferlinopathy, and sarcoglycanopathis. DNA sample of the proband was sent for NGS. Whole exome sequencing (WES) revealed a novel mutation c.1295delA in exon 13 of MICU1 gene. This homozygous deletion creates a frameshift and a premature stop codon downstream of canonical EF4 calcium binding motif of MICU1. According to the American College of Medical Genetics and Genomics (ACMG) guidline for sequence interpretation, this variant was a pathogenic one. Sanger sequencing in all family members confirmed the results of the WES. CONCLUSIONS: This study was the first report of MPXPS in Iranian population which also revealed a novel mutation in the MICU1 gene.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Proteínas de Transporte de Cátions/genética , Repetições de Microssatélites/genética , Proteínas de Transporte da Membrana Mitocondrial/genética , Doenças Musculares/genética , Distrofia Muscular do Cíngulo dos Membros/genética , Pré-Escolar , Exoma/genética , Éxons/genética , Tratos Extrapiramidais/metabolismo , Tratos Extrapiramidais/patologia , Feminino , Mutação da Fase de Leitura/genética , Sequenciamento de Nucleotídeos em Larga Escala , Homozigoto , Humanos , Irã (Geográfico)/epidemiologia , Doenças Musculares/patologia , Distrofia Muscular do Cíngulo dos Membros/patologia , Linhagem , Deleção de Sequência/genética , Sequenciamento do Exoma
10.
J Neurogenet ; 31(3): 161-169, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28687063

RESUMO

Sarcoglycanopathies (SGCs) which are caused by mutations in SGCA, SGCB, SGCG or SGCD genes are a subgroup of autosomal-recessive limb-girdle-muscular-dystrophies (LGMD2). Although frequencies of mutations in these genes are different among populations, mutations in SGCA and SGCD, respectively, have the highest and lowest frequencies in most populations. Here, we report the proportion of mutations in SGC genes among a group of Iranian SGCs patients. Clinical features and results of SGC genes screening of 25 SGCs probands are presented. Large deletion mutations are confirmed with MLPA assays. In total, 15 candidate disease causing mutations were observed in the SGCA, SGCB, SGCG and SGCD genes; ten were novel. Fourteen (56%), seven (28%), three (12%) and one (4%) patient, respectively, carried mutations in SGCB, SGCG, SGCD and SGCA. The findings suggest that LGMD2E is the most common form of SGCs in the Iranian population and that LGMD2D is the rarest. Twelve LGMD2E cases carried the same mutation. To the best of knowledge, the mutation spectrum in SGCs is being reported for the first time in Iranian population. The finding will be beneficial for screening and genetic-counseling of SGCs patients in Iran.


Assuntos
Mutação/genética , Sarcoglicanopatias/epidemiologia , Sarcoglicanopatias/genética , Adolescente , Adulto , Criança , Saúde da Família , Feminino , Técnicas Genéticas , Haplótipos , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Estudos Retrospectivos , Adulto Jovem
11.
Muscle Nerve ; 55(6): 835-840, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27649523

RESUMO

INTRODUCTION: Pompe disease is characterized by absence or deficiency of acid α-glucosidase, and several causative mutations are known. In this study we report clinical and laboratory data in Iranian patients with late-onset Pompe disease (LOPD), focusing on population-specific mutations. METHODS: Clinical and laboratory data of 14 patients from 10 families with the diagnosis of LOPD were recorded. All had reduced enzyme activity on dried blood spot (DBS) analysis. Genetic investigation was performed to identify the underlying mutations. RESULTS: The age of onset ranged from <2 to 38 years. The clinical presentations were heterogeneous. Two siblings presented with foot drop. The most common mutation was c.(-32-13T>G). There were 4 novel mutations: c.(2040 + 2dup); c.(1650delG); c.(1837T>G); and c.(2596delG). CONCLUSION: This is a comprehensive report of LOPD in Iranian patients. Distinct phenotypic and genotypic features in this population are highlighted. Muscle Nerve 55: 835-840, 2017.


Assuntos
Predisposição Genética para Doença/genética , Doença de Depósito de Glicogênio Tipo II , Mutação/genética , alfa-Glucosidases/genética , Adolescente , Criança , Pré-Escolar , Consanguinidade , Eletromiografia , Potencial Evocado Motor/genética , Saúde da Família , Feminino , Genótipo , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Doença de Depósito de Glicogênio Tipo II/genética , Doença de Depósito de Glicogênio Tipo II/terapia , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Transtornos Respiratórios/etiologia , Adulto Jovem
12.
J Neurogenet ; 30(1): 1-4, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-27276190

RESUMO

Sarcoglycanopathies (SGPs) constitute a subgroup of autosomal recessive limb girdle muscular dystrophies (LGMDs) which are caused by mutations in sarcoglycan (SGs) genes. SG proteins form a core complex consisting of α, ß, γ and δ sarcoglycans which are encoded by SGCA, SGCB, SGCG and SGCD genes, respectively. Genetic defect, in any of these SG proteins, results in instability of the whole complex. This effect can be helpful in interpreting muscle biopsy results. Autozygosity mapping is a gene mapping approach which can be applied in large consanguineous families for tracking the defective gene in most autosomal recessive disorders. In the present study, we used autozygosity mapping, to find the gene responsible for muscular dystrophy. Proband was a 10-year-old boy referred to our center for ruling out DMD (Duchenne muscular dystrophy). According to the pedigree and clinical reports, we assessed him for SGPs. Haplotyping, using the four short tandem repeat (STR) markers for each of the SG genes, showed that the phenotype may segregate with SGCB gene; and observing two crossing overs which occurred within the gene suggested that the mutation might be in the first two exons of SGCB gene. Mutation analysis showed a 26 bp duplication (10 bp before the initiation codon till 13 bp after the ATG start codon). This will cause a frameshift in protein synthesis.


Assuntos
Mapeamento Cromossômico/métodos , Distrofia Muscular do Cíngulo dos Membros/genética , Sarcoglicanas/genética , Adulto , Criança , Análise Mutacional de DNA , Feminino , Humanos , Irã (Geográfico) , Masculino , Linhagem
13.
BMC Neurol ; 15: 205, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26471939

RESUMO

BACKGROUND: Pompe disease is a rare autosomal recessive disorder caused by a deficiency of the lysosomal enzyme alpha-glucosidase responsible for degrading glycogen. Late-onset Pompe disease has a complex multisystem phenotype characterized by a range of symptoms. METHODS: An expert panel from the Middle East and North Africa (MENA) region met to create consensus-based guidelines for the diagnosis and treatment of late-onset Pompe disease for the MENA region, where the relative prevalence of Pompe disease is thought to be high but there is a lack of awareness and diagnostic facilities. RESULTS: These guidelines set out practical recommendations and include algorithms for the diagnosis and treatment of late-onset Pompe disease. They detail the ideal diagnostic workup, indicate the patients in whom enzyme replacement therapy should be initiated, and provide guidance on appropriate patient monitoring. CONCLUSIONS: These guidelines will serve to increase awareness of the condition, optimize patient diagnosis and treatment, reduce disease burden, and improve patient outcomes.


Assuntos
Consenso , Doença de Depósito de Glicogênio Tipo II/diagnóstico , Doença de Depósito de Glicogênio Tipo II/terapia , Guias de Prática Clínica como Assunto , África do Norte/epidemiologia , Doença de Depósito de Glicogênio Tipo II/epidemiologia , Doença de Depósito de Glicogênio Tipo II/genética , Humanos , Oriente Médio/epidemiologia
14.
Neurol Sci ; 36(11): 2011-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26081009

RESUMO

Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) are the most frequent muscular dystrophies. Present study aimed to determine the frequency of dystrophin gene alterations in Iranian DMD/BMD patients using molecular techniques. 146 Iranian DMD/BMD patients have been analyzed using two devised sets of multiplex polymerase chain reaction (M-PCR) followed by multiple ligation-dependent probe amplification (MLPA). Two isolated DMD and BMD patients were analyzed by DNA sequencing. 30.9 % of patients had single-exon deletion while group and contiguous exon deletions were identified in 41 % of the patients. The most numerous exon deletions included exons 45-50 and were identified in the first M-PCR set. Deletion detection rate was 99 % in first M-PCR set and remaining deletions (1 %) were identified in the second M-PCR set. MLPA analysis showed that there were two exons 3-5 and 41-43 duplications (1.4 %) in a BMD and a DMD patient, respectively. Two nonsense mutations including c.633dupA and c.6283 C>T were, respectively, found in a DMD and BMD patient in which c.633dupA has not ever been reported in DMD mutation database and was pathogenic mutation. Besides the report of frequency of dystrophin gene alteration in a subset of Iranian DMD/BMD patients, it was revealed that the proposed M-PCR protocol can be useful in the initial step of molecular diagnosis of DMD/BMD. Exon sequencing would be the final step in determining the mutation status of DMD/BMD patients following MLPA.


Assuntos
Códon sem Sentido , Éxons , Deleção de Genes , Distrofia Muscular de Duchenne/genética , Criança , Humanos , Irã (Geográfico) , Masculino , Estudos Retrospectivos , Análise de Sequência de DNA/métodos
15.
Am J Hum Genet ; 88(2): 162-72, 2011 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-21310273

RESUMO

Neuromuscular junctions (NMJs) are synapses that transmit impulses from motor neurons to skeletal muscle fibers leading to muscle contraction. Study of hereditary disorders of neuromuscular transmission, termed congenital myasthenic syndromes (CMS), has helped elucidate fundamental processes influencing development and function of the nerve-muscle synapse. Using genetic linkage, we find 18 different biallelic mutations in the gene encoding glutamine-fructose-6-phosphate transaminase 1 (GFPT1) in 13 unrelated families with an autosomal recessive CMS. Consistent with these data, downregulation of the GFPT1 ortholog gfpt1 in zebrafish embryos altered muscle fiber morphology and impaired neuromuscular junction development. GFPT1 is the key enzyme of the hexosamine pathway yielding the amino sugar UDP-N-acetylglucosamine, an essential substrate for protein glycosylation. Our findings provide further impetus to study the glycobiology of NMJ and synapses in general.


Assuntos
Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/genética , Hexosaminas/metabolismo , Mutação/genética , Síndromes Miastênicas Congênitas/genética , Transdução de Sinais , Animais , Western Blotting , Estudos de Casos e Controles , Células Cultivadas , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Feminino , Imunofluorescência , Regulação da Expressão Gênica no Desenvolvimento , Ligação Genética , Glicosilação , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Masculino , Síndromes Miastênicas Congênitas/patologia , Junção Neuromuscular/fisiologia , Linhagem , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transmissão Sináptica/fisiologia , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
16.
J Res Med Sci ; 19(8): 792-4, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25422667

RESUMO

Hereditary inclusion body myopathy (hIBM) is an adult-onset hereditary myopathy, usually with distal onset and quadriceps sparing. This myopathy is autosomal recessive and associated to UPD-N-acetylglucosamine-2-epimerase/N-acetylmannosamine kinase (GNE) gene mutations. In this study, we report a novel GNE homozygous point mutation c.1834T>G that results in amino acid substitution of cysteine 612 to glutamine in an Iranian patient. This mutation is located in exon 10 within the kinase domain of the protein.

17.
Diabetol Metab Syndr ; 16(1): 161, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39004753

RESUMO

BACKGROUND: Episodes of recurrent or severe hypoglycemia can occur in patients with diabetes mellitus, insulinoma, neonatal hypoglycemia, and medication errors. However, little is known about the short-term and long-term effects of repeated episodes of acute severe hypoglycemia on the brain, particularly in relation to hippocampal damage and cognitive dysfunction. METHODS: Thirty-six wistar rats were randomly assigned to either the experimental or control group. The rats were exposed to severe hypoglycemia, and assessments were conducted to evaluate oxidative stress in brain tissue, cognitive function using the Morris water maze test, as well as histopathology and immunohistochemistry studies. The clinical and histopathological evaluations were conducted in the short-term and long-term. RESULTS: The mortality rate attributed to hypoglycemia was 34%, occurring either during hypoglycemia or within 24 h after induction. Out of the 14 rats monitored for 7 to 90 days following severe/recurrent hypoglycemia, all exhibited clinical symptoms, which mostly resolved within three days after the last hypoglycemic episode, except for three rats. Despite the decrease in catalase activity in the brain, the total antioxidant capacity following severe insulin-induced hypoglycemia increased. The histopathology findings revealed that the severity of the hippocampal damage was higher compared to the brain cortex 90 days after hypoglycemia. Memory impairments with neuron loss particularly pronounced in the dentate gyrus region of the hippocampus were observed in the rats with severe hypoglycemia. Additionally, there was an increase in reactive astrocytes indicated by GFAP immunoreactivity in the brain cortex and hippocampus. CONCLUSION: Recurrent episodes of severe hypoglycemia can lead to high mortality rates, memory impairments, and severe histopathological changes in the brain. While many histopathological and clinical changes improved after three months, it seems that the vulnerability of the hippocampus and the development of sustained changes in the hippocampus were greater and more severe compared to the brain cortex following severe and recurrent hypoglycemia. Furthermore, it does not appear that oxidative stress plays a central role in neuronal damage following severe insulin-induced hypoglycemia. Further research is necessary to assess the consequences of repeated hypoglycemic episodes on sustained damage across various brain regions.

18.
Mol Genet Genomic Med ; 12(7): e2489, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38967380

RESUMO

BACKGROUND: Glutaric aciduria type II (GA2) is a rare genetic disorder inherited in an autosomal recessive manner. Double dosage mutations in GA2 corresponding genes, ETFDH, ETFA, and ETFB, lead to defects in the catabolism of fatty acids, and amino acids lead to broad-spectrum phenotypes, including muscle weakness, developmental delay, and seizures. product of these three genes have crucial role in transferring electrons to the electron transport chain (ETC), but are not directly involve in ETC complexes. METHODS: Here, by using exome sequencing, the cause of periodic cryptic gastrointestinal complications in a 19-year-old girl was resolved after years of diagnostic odyssey. Protein modeling for the novel variant served as another line of validation for it. RESULTS: Exome Sequencing (ES) identified two variants in ETFDH: ETFDH:c.926T>G and ETFDH:c.1141G>C. These variants are likely contributing to the crisis in this case. To the best of our knowledge at the time of writing this manuscript, variant ETFDH:c.926T>G is reported here for the first time. Clinical manifestations of the case and pathological analysis are in consistent with molecular findings. Protein modeling provided another line of evidence proving the pathogenicity of the novel variant. ETFDH:c.926T>G is reported here for the first time in relation to the causation GA2. CONCLUSION: Given the milder symptoms in this case, a review of GA2 cases caused by compound heterozygous mutations was conducted, highlighting the range of symptoms observed in these patients, from mild fatigue to more severe outcomes. The results underscore the importance of comprehensive genetic analysis in elucidating the spectrum of clinical presentations in GA2 and guiding personalized treatment strategies.


Assuntos
Flavoproteínas Transferidoras de Elétrons , Heterozigoto , Proteínas Ferro-Enxofre , Oxirredutases atuantes sobre Doadores de Grupo CH-NH , Humanos , Feminino , Flavoproteínas Transferidoras de Elétrons/genética , Proteínas Ferro-Enxofre/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Adulto Jovem , Encefalopatias Metabólicas/genética , Encefalopatias Metabólicas/patologia , Encefalopatias Metabólicas/diagnóstico , Mutação , Deficiência Múltipla de Acil Coenzima A Desidrogenase/genética , Deficiência Múltipla de Acil Coenzima A Desidrogenase/patologia
19.
Neuromuscul Disord ; 35: 19-24, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38194732

RESUMO

The rare disorder known as Neutral Lipid Storage Disease with Myopathy presents with a variety of clinical manifestations, including myopathy, cardiac dysfunction, and other organ complications. Early diagnosis is crucial due to the increased risk of cardiomyopathy. We describe the clinical, histopathological, muscle imaging, and genetic findings of nine neutral lipid storage myopathy patients. Proximal weakness and asymmetric involvement may suggest lipid storage myopathy. While skeletal muscle weakness was the main manifestation in our patients, one case presented only with hyperCKemia. Additionally, three patients had fertility issues, two suffered from diabetes mellitus, two had cardiomyopathy, and one had a history of hypothyroidism. Muscle histopathology revealed lipid depositions and rimmed vacuoles, prompting peripheral blood smears to detect Jordan Anomalies. All muscle biopsies and peripheral blood smear showed lipid droplets, rimmed vacuoles, and Jordan anomaly. Identifying PNPLA2 gene mutations is important for diagnosing neutral lipid storage myopathy; our cases showed some novel mutations. This study highlights the importance of early diagnosis and comprehensive evaluation in managing neutral lipid storage myopathy cases.


Assuntos
Cardiomiopatias , Eritrodermia Ictiosiforme Congênita , Erros Inatos do Metabolismo Lipídico , Doenças Musculares , Humanos , Irã (Geográfico) , Músculo Esquelético/patologia , Lipase/genética , Doenças Musculares/diagnóstico , Doenças Musculares/genética , Doenças Musculares/patologia , Erros Inatos do Metabolismo Lipídico/diagnóstico , Erros Inatos do Metabolismo Lipídico/genética , Erros Inatos do Metabolismo Lipídico/patologia , Cardiomiopatias/diagnóstico , Cardiomiopatias/genética , Cardiomiopatias/patologia , Mutação
20.
Clin Case Rep ; 12(8): e9251, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39104734

RESUMO

Homozygous variants of Calcium Voltage-Gated Channel Subunit Alpha1 S (CACNA1S) gene mutation were previously identified as causes of periodic paralysis and congenital early-onset myopathy, while it could be manifested as a late-onset congenital core myopathy. Abstract: Calcium Voltage-Gated Channel Subunit Alpha1 S (CACNA1S) gene mutation has been linked to various neuromuscular conditions in recent years. Congenital myopathy with core-like features is one of the cardinal associations reported previously, causing severe respiratory insufficiency and death in neonates. Informed consent was received from the patients. Subsequently, peripheral blood leukocytes were utilized to extract genomic DNA. Moreover, exome enrichment was implemented through the Twist Human Core Exome Kit (Twist Bioscience) and exome sequenced using Illumina NovaSeq 6000 platform (Illumina, San Diego, CA, USA). Sanger sequencing using BIG Dye Terminators confirmed the presence of the final variant. Finally, the candidate variants were classified based on the American College of Medical Genetics and Genomics (ACMG) guidelines. In this report, we describe two siblings, who presented with childhood and late-onset progressive muscle weakness, and had a homozygous variant in exon 2 of the CACNA1S gene defined as c.188C > A (p.Ala63Asp) (NM_000069.3). The SIFT, Polyphen2, CADD PHRED, and Mutation Taster analysis tools classified the variant as pathogenic/damaging. The muscle biopsy of the younger brother revealed intermyofibrillar network pattern disruption as cytoplasmic core-like lesions. The muscle magnetic resonance imaging (MRI) reported grade IIa and IIb fatty changes. Finally, the electromyography (EMG) findings suggested a myopathic change pattern. This report illustrates the clinical variability in CACNA1S-related myopathy by reviewing prior reports and adding newly found aspects, additionally expanding the gene defects associated with core myopathy.

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