GNE myopathy: from clinics and genetics to pathology and research strategies.
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ABSTRACT:
SUBMITTER: Pogoryelova O
PROVIDER: S-EPMC5930817 | biostudies-literature | 2018 May
REPOSITORIES: biostudies-literature
Publications
GNE myopathy: from clinics and genetics to pathology and research strategies.
Pogoryelova Oksana O González Coraspe José Andrés JA Nikolenko Nikoletta N Lochmüller Hanns H Roos Andreas A
Orphanet journal of rare diseases 20180502 1
GNE myopathy is an ultra-rare autosomal recessive disease, which starts as a distal muscle weakness and ultimately leads to a wheelchair bound state. Molecular research and animal modelling significantly moved forward understanding of GNE myopathy mechanisms and suggested therapeutic interventions to alleviate the symptoms. Multiple therapeutic attempts are being made to supplement sialic acid depleted in GNE myopathy muscle cells. Translational research field provided valuable knowledge through ...[more]
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Project description:GNE myopathy is a rare, recessively inherited, early adult-onset myopathy, characterized by distal and proximal muscle degeneration which often spares the quadriceps. It is caused by mutations in the UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase gene (GNE). This study aimed to identify the disease-causing mutation in a three-generation Han-Chinese family with members who have been diagnosed with myopathy. A homozygous missense mutation, c.1627G>A (p.V543M) in the GNE gene co-segregates with the myopathy present in this family. A GNE myopathy diagnosis is evidenced by characteristic clinical manifestations, rimmed vacuoles in muscle biopsies and the presence of biallelic GNE mutations. This finding broadens the GNE gene mutation spectrum and extends the GNE myopathy phenotype spectrum.
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Project description:INTRODUCTION:GNE myopathy is an adult-onset muscle disorder characterized by impaired sialylation of (muscle) glycans, detectable by lectin histochemistry. We describe a standardized method to quantify (lectin-) fluorescence in muscle sections, applicable for diagnosis and response to therapy for GNE myopathy. METHODS:Muscle sections were fluorescently labeled with the sialic acid-binding Sambucus nigra agglutinin (SNA) lectin and antibodies to sarcolemma residence protein caveolin-3 (CAV-3). Entire tissue sections were imaged in tiles and fluorescence was quantified. RESULTS:SNA fluorescence co-localizing with CAV-3 was ?50% decreased in GNE myopathy biopsies compared with muscle-matched controls, confirming previous qualitative results. DISCUSSION:This quantitative fluorescence method can accurately determine sialylation status of GNE myopathy muscle biopsies. This method is adaptable for expression of other membrane-associated muscle proteins, and may be of benefit for disorders in which therapeutic changes in expression are subtle and difficult to assess by other methods. Muscle Nerve 58: 286-292, 2018.
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