Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029089 (ophthalmoplegia)
 3,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mutations in OPA1, a dynamin-related GTPase involved in mitochondrial fusion, cristae organization and control of apoptosis, have been linked to non-syndromic optic neuropathy transmitted as an autosomal-dominant trait (DOA). We here report on eight patients from six independent families showing that mutations in the OPA1 gene can also be responsible for a syndromic form of DOA associated with sensorineural deafness, ataxia, axonal sensory-motor polyneuropathy, chronic progressive external ophthalmoplegia and mitochondrial myopathy with cytochrome c oxidase negative and Ragged Red Fibres. Most remarkably, we demonstrate that these patients all harboured multiple deletions of mitochondrial DNA (mtDNA) in their skeletal muscle, thus revealing an unrecognized role of the OPA1 protein in mtDNA stability. The five OPA1 mutations associated with these DOA 'plus' phenotypes were all mis-sense point mutations affecting highly conserved amino acid positions and the nuclear genes previously known to induce mtDNA multiple deletions such as POLG1, PEO1 (Twinkle) and SLC25A4 (ANT1) were ruled out. Our results show that certain OPA1 mutations exert a dominant negative effect responsible for multi-systemic disease, closely related to classical mitochondrial cytopathies, by a mechanism involving mtDNA instability.
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PMID:OPA1 mutations induce mitochondrial DNA instability and optic atrophy 'plus' phenotypes. 1822 90

Mutations in dynamin-2 (DNM2) cause autosomal dominant centronuclear myopathy (CNM). We report a series of 12 patients from eight families with CNM in whom we have identified a number of novel features that expand the reported clinicopathological phenotype. We identified two novel and five recurrent missense mutations in DNM2. Early clues to the diagnosis include relative weakness of neck flexors, external ophthalmoplegia and ptosis, although these are not present in all patients. Pes cavus was present in two patients, and in another two members of one family there was mild slowing of nerve conduction velocities. Whole-body MRI examination in two children and one adult revealed a similar pattern of involvement of selective muscles in head (lateral pterygoids), neck (extensors), trunk (paraspinal) and upper limbs (deep muscles of forearm). Findings in lower limbs and pelvic region were similar to that previously reported in adults with DNM2 mutations. Two patients presented with dystrophic changes as the predominant pathological feature on muscle biopsies; one of whom had a moderately raised creatine kinase, and both patients were initially diagnosed as congenital muscular dystrophy. DNM2 mutation analysis should be considered in patients with a suggestive clinical phenotype despite atypical histopathology, and MRI findings can be used to guide genetic testing. Subtle neuropathic features in some patients suggest an overlap with the DNM2 neuropathy phenotype. Missense mutations in the C-terminal region of the PH domain appear to be associated with a more severe clinical phenotype evident from infancy.
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PMID:Expanding the clinical, pathological and MRI phenotype of DNM2-related centronuclear myopathy. 2022 76

Mutations in the dynamin-2 (DNM2) gene can cause autosomal dominant or sporadic centronuclear myopathy (CNM). We aimed to analyze the clinical, pathological and genetic characteristic of patients with DNM2-related CNM in China. We studied seven patients, all of whom underwent clinical examination, muscle biopsy, electromyography, and genetic tests. DNM2 gene analysis revealed two sporadic patients harboring the p.E368K mutation, two patients from one family carrying p.R369Q, one with p.R369W, one with p.R523G and one with compound heterozygous mutations of p.R522H and p.R718Q. In DNM2-related CNM, ptosis, ophthalmoplegia/paresis, and facial weakness are the frequently observed manifestations. However, among these seven patients, only one had bilateral ptosis; one, external ophthalmoplegia and one, facial weakness. Muscle biopsy showed that the percentage of muscle fibers with centrally located nuclei ranged from 67 to 93 %, all with radial sarcoplasmic strands. To date, five different CNM-related DNM2 mutations have been observed in China. Here, a patient with compound heterozygous DNM2 mutations was reported for the first time. Facial weakness, ptosis and ophthalmoplegia did not appear to be common in Chinese patients. This study on Chinese patients broadens the spectrum of DNM2-related CNM.
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PMID:Clinical, pathological, and genetic features of dynamin-2-related centronuclear myopathy in China. 2550 59