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Rocatcher A, Desquiret-Dumas V, Charif M, Ferré M, Gohier P, Mirebeau-Prunier D, Verny C, Milea D, Lenaers G, Bonneau D, Reynier P, Amati-Bonneau P. The top 10 most frequently involved genes in hereditary optic neuropathies in 2186 probands. Brain 2023; 146:455-460. [PMID: 36317462 DOI: 10.1093/brain/awac395] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 09/15/2022] [Accepted: 09/25/2022] [Indexed: 12/12/2022] Open
Abstract
Hereditary optic neuropathies are caused by the degeneration of retinal ganglion cells whose axons form the optic nerves, with a consistent genetic heterogeneity. As part of our diagnostic activity, we retrospectively evaluated the combination of Leber hereditary optic neuropathy mutations testing with the exon sequencing of 87 nuclear genes on 2186 patients referred for suspected hereditary optic neuropathies. The positive diagnosis rate in individuals referred for Leber hereditary optic neuropathy testing was 18% (199/1126 index cases), with 92% (184/199) carrying one of the three main pathogenic variants of mitochondrial DNA (m.11778G>A, 66.5%; m.3460G>A, 15% and m.14484T>C, 11%). The positive diagnosis rate in individuals referred for autosomal dominant or recessive optic neuropathies was 27% (451/1680 index cases), with 10 genes accounting together for 96% of this cohort. This represents an overall positive diagnostic rate of 30%. The identified top 10 nuclear genes included OPA1, WFS1, ACO2, SPG7, MFN2, AFG3L2, RTN4IP1, TMEM126A, NR2F1 and FDXR. Eleven additional genes, each accounting for less than 1% of cases, were identified in 17 individuals. Our results show that 10 major genes account for more than 96% of the cases diagnosed with our nuclear gene panel.
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Affiliation(s)
- Aude Rocatcher
- Département d'Ophtalmologie, Centre Hospitalier Universitaire d'Angers, 49933 Angers, France
| | - Valérie Desquiret-Dumas
- Université d'Angers, Centre National de la Recherche Scientifique (CNRS 6015), Institut National de la Santé et de la Recherche Médicale (INSERM U1083), Unité Mixte de Recherche (UMR) MITOVASC, 49000 Angers, France
| | - Majida Charif
- Université d'Angers, Centre National de la Recherche Scientifique (CNRS 6015), Institut National de la Santé et de la Recherche Médicale (INSERM U1083), Unité Mixte de Recherche (UMR) MITOVASC, 49000 Angers, France
- Genetics and Immuno-Cell Therapy Team, Mohammed First University, Oujda 60000, Morocco
| | - Marc Ferré
- Université d'Angers, Centre National de la Recherche Scientifique (CNRS 6015), Institut National de la Santé et de la Recherche Médicale (INSERM U1083), Unité Mixte de Recherche (UMR) MITOVASC, 49000 Angers, France
| | - Philippe Gohier
- Département d'Ophtalmologie, Centre Hospitalier Universitaire d'Angers, 49933 Angers, France
| | - Delphine Mirebeau-Prunier
- Université d'Angers, Centre National de la Recherche Scientifique (CNRS 6015), Institut National de la Santé et de la Recherche Médicale (INSERM U1083), Unité Mixte de Recherche (UMR) MITOVASC, 49000 Angers, France
| | - Christophe Verny
- Université d'Angers, Centre National de la Recherche Scientifique (CNRS 6015), Institut National de la Santé et de la Recherche Médicale (INSERM U1083), Unité Mixte de Recherche (UMR) MITOVASC, 49000 Angers, France
- Département de Neurologie, Centre Hospitalier Universitaire d'Angers, 49933 Angers, France
| | - Dan Milea
- Département d'Ophtalmologie, Centre Hospitalier Universitaire d'Angers, 49933 Angers, France
- Singapore National Eye Centre, Singapore Eye Research Institute, Duke-NUS 169857, Singapore
| | - Guy Lenaers
- Université d'Angers, Centre National de la Recherche Scientifique (CNRS 6015), Institut National de la Santé et de la Recherche Médicale (INSERM U1083), Unité Mixte de Recherche (UMR) MITOVASC, 49000 Angers, France
- Département de Neurologie, Centre Hospitalier Universitaire d'Angers, 49933 Angers, France
| | - Dominique Bonneau
- Université d'Angers, Centre National de la Recherche Scientifique (CNRS 6015), Institut National de la Santé et de la Recherche Médicale (INSERM U1083), Unité Mixte de Recherche (UMR) MITOVASC, 49000 Angers, France
- Département de Génétique, Centre Hospitalier Universitaire d'Angers, 49933 Angers, France
| | - Pascal Reynier
- Université d'Angers, Centre National de la Recherche Scientifique (CNRS 6015), Institut National de la Santé et de la Recherche Médicale (INSERM U1083), Unité Mixte de Recherche (UMR) MITOVASC, 49000 Angers, France
- Département de Biochimie et Biologie Moléculaire, Centre Hospitalier Universitaire d'Angers, 49933 Angers, France
| | - Patrizia Amati-Bonneau
- Université d'Angers, Centre National de la Recherche Scientifique (CNRS 6015), Institut National de la Santé et de la Recherche Médicale (INSERM U1083), Unité Mixte de Recherche (UMR) MITOVASC, 49000 Angers, France
- Département de Biochimie et Biologie Moléculaire, Centre Hospitalier Universitaire d'Angers, 49933 Angers, France
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2
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Kabanovski A, Donaldson L, Margolin E. Neuro-ophthalmological manifestations of Wolfram syndrome: Case series and review of the literature. J Neurol Sci 2022; 437:120267. [DOI: 10.1016/j.jns.2022.120267] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 04/03/2022] [Accepted: 04/15/2022] [Indexed: 12/13/2022]
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3
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Murakhovskaya YK, Sheremet NL, Shmelkova MS, Krylova TD, Tsygankova PG. [Autosomal recessive optic neuropathies: genetic variants, clinical manifestations]. Vestn Oftalmol 2022; 138:116-122. [PMID: 36573955 DOI: 10.17116/oftalma2022138061116] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Hereditary optic neuropathies (HON) - a group of neurodegenerative diseases characterized by primary loss of structure and function of the retinal ganglion cells and subsequent death of their axons, development of partial optic nerve atrophy. Autosomal dominant optic neuropathy and Leber`s hereditary optic neuropathy until recently were considered the most common genetic hereditary optic neuropathies, while autosomal recessive optic neuropathies (ARON) were described as rare types of HON, usually accompanying severe syndromic pathologies. In the 2000s it has become clear that ARON occur significantly more often, are underestimated, and their clinical variability is poorly studied. Despite the fact that non-syndromic ARON are less common than syndromic optic neuropathies, their contribution to the development of isolated hereditary optic neuropathies should be considered. This article presents a literature review on non-syndromic ARON developing as a result of mutations in the ACO2, MCAT, WFS1, RTN4IP1, TMEM126A, NDUFS2, DNAJC30 genes.
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Affiliation(s)
- Yu K Murakhovskaya
- Krasnov Research Institute of Eye Diseases, Moscow, Russia.,I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - N L Sheremet
- Krasnov Research Institute of Eye Diseases, Moscow, Russia
| | - M S Shmelkova
- Krasnov Research Institute of Eye Diseases, Moscow, Russia
| | - T D Krylova
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
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4
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Strachan EL, Mac White-Begg D, Crean J, Reynolds AL, Kennedy BN, O'Sullivan NC. The Role of Mitochondria in Optic Atrophy With Autosomal Inheritance. Front Neurosci 2021; 15:784987. [PMID: 34867178 PMCID: PMC8634724 DOI: 10.3389/fnins.2021.784987] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 10/22/2021] [Indexed: 11/13/2022] Open
Abstract
Optic atrophy (OA) with autosomal inheritance is a form of optic neuropathy characterized by the progressive and irreversible loss of vision. In some cases, this is accompanied by additional, typically neurological, extra-ocular symptoms. Underlying the loss of vision is the specific degeneration of the retinal ganglion cells (RGCs) which form the optic nerve. Whilst autosomal OA is genetically heterogenous, all currently identified causative genes appear to be associated with mitochondrial organization and function. However, it is unclear why RGCs are particularly vulnerable to mitochondrial aberration. Despite the relatively high prevalence of this disorder, there are currently no approved treatments. Combined with the lack of knowledge concerning the mechanisms through which aberrant mitochondrial function leads to RGC death, there remains a clear need for further research to identify the underlying mechanisms and develop treatments for this condition. This review summarizes the genes known to be causative of autosomal OA and the mitochondrial dysfunction caused by pathogenic mutations. Furthermore, we discuss the suitability of available in vivo models for autosomal OA with regards to both treatment development and furthering the understanding of autosomal OA pathology.
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Affiliation(s)
- Elin L Strachan
- UCD Conway Institute, University College Dublin, Dublin, Ireland.,UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
| | - Delphi Mac White-Begg
- UCD Conway Institute, University College Dublin, Dublin, Ireland.,UCD School of Veterinary Medicine, University College Dublin, Dublin, Ireland
| | - John Crean
- UCD Conway Institute, University College Dublin, Dublin, Ireland.,UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland.,UCD Diabetes Complications Research Centre, Conway Institute of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
| | - Alison L Reynolds
- UCD Conway Institute, University College Dublin, Dublin, Ireland.,UCD School of Veterinary Medicine, University College Dublin, Dublin, Ireland
| | - Breandán N Kennedy
- UCD Conway Institute, University College Dublin, Dublin, Ireland.,UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
| | - Niamh C O'Sullivan
- UCD Conway Institute, University College Dublin, Dublin, Ireland.,UCD School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
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Zanfardino P, Doccini S, Santorelli FM, Petruzzella V. Tackling Dysfunction of Mitochondrial Bioenergetics in the Brain. Int J Mol Sci 2021; 22:8325. [PMID: 34361091 PMCID: PMC8348117 DOI: 10.3390/ijms22158325] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 12/15/2022] Open
Abstract
Oxidative phosphorylation (OxPhos) is the basic function of mitochondria, although the landscape of mitochondrial functions is continuously growing to include more aspects of cellular homeostasis. Thanks to the application of -omics technologies to the study of the OxPhos system, novel features emerge from the cataloging of novel proteins as mitochondrial thus adding details to the mitochondrial proteome and defining novel metabolic cellular interrelations, especially in the human brain. We focussed on the diversity of bioenergetics demand and different aspects of mitochondrial structure, functions, and dysfunction in the brain. Definition such as 'mitoexome', 'mitoproteome' and 'mitointeractome' have entered the field of 'mitochondrial medicine'. In this context, we reviewed several genetic defects that hamper the last step of aerobic metabolism, mostly involving the nervous tissue as one of the most prominent energy-dependent tissues and, as consequence, as a primary target of mitochondrial dysfunction. The dual genetic origin of the OxPhos complexes is one of the reasons for the complexity of the genotype-phenotype correlation when facing human diseases associated with mitochondrial defects. Such complexity clinically manifests with extremely heterogeneous symptoms, ranging from organ-specific to multisystemic dysfunction with different clinical courses. Finally, we briefly discuss the future directions of the multi-omics study of human brain disorders.
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Affiliation(s)
- Paola Zanfardino
- Department of Medical Basic Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, 70124 Bari, Italy;
| | - Stefano Doccini
- IRCCS Fondazione Stella Maris, Calambrone, 56128 Pisa, Italy;
| | | | - Vittoria Petruzzella
- Department of Medical Basic Sciences, Neurosciences and Sense Organs, University of Bari Aldo Moro, 70124 Bari, Italy;
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Weisschuh N, Schimpf-Linzenbold S, Mazzola P, Kieninger S, Xiao T, Kellner U, Neuhann T, Kelbsch C, Tonagel F, Wilhelm H, Kohl S, Wissinger B. Mutation spectrum of the OPA1 gene in a large cohort of patients with suspected dominant optic atrophy: Identification and classification of 48 novel variants. PLoS One 2021; 16:e0253987. [PMID: 34242285 PMCID: PMC8270428 DOI: 10.1371/journal.pone.0253987] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 06/17/2021] [Indexed: 12/18/2022] Open
Abstract
Autosomal dominant optic atrophy is one of the most common inherited optic neuropathies. This disease is genetically heterogeneous, but most cases are due to pathogenic variants in the OPA1 gene: depending on the population studied, 32–90% of cases harbor pathogenic variants in this gene. The aim of this study was to provide a comprehensive overview of the entire spectrum of likely pathogenic variants in the OPA1 gene in a large cohort of patients. Over a period of 20 years, 755 unrelated probands with a diagnosis of bilateral optic atrophy were referred to our laboratory for molecular genetic investigation. Genetic testing of the OPA1 gene was initially performed by a combined analysis using either single-strand conformation polymorphism or denaturing high performance liquid chromatography followed by Sanger sequencing to validate aberrant bands or melting profiles. The presence of copy number variations was assessed using multiplex ligation-dependent probe amplification. Since 2012, genetic testing was based on next-generation sequencing platforms. Genetic screening of the OPA1 gene revealed putatively pathogenic variants in 278 unrelated probands which represent 36.8% of the entire cohort. A total of 156 unique variants were identified, 78% of which can be considered null alleles. Variant c.2708_2711del/p.(V903Gfs*3) was found to constitute 14% of all disease-causing alleles. Special emphasis was placed on the validation of splice variants either by analyzing cDNA derived from patients´ blood samples or by heterologous splice assays using minigenes. Splicing analysis revealed different aberrant splicing events, including exon skipping, activation of exonic or intronic cryptic splice sites, and the inclusion of pseudoexons. Forty-eight variants that we identified were novel. Nine of them were classified as pathogenic, 34 as likely pathogenic and five as variant of uncertain significance. Our study adds a significant number of novel variants to the mutation spectrum of the OPA1 gene and will thereby facilitate genetic diagnostics of patients with suspected dominant optic atrophy.
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Affiliation(s)
- Nicole Weisschuh
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Simone Schimpf-Linzenbold
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany.,CeGaT GmbH and Praxis für Humangenetik Tübingen, Tübingen, Germany
| | - Pascale Mazzola
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Sinja Kieninger
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Ting Xiao
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Ulrich Kellner
- Zentrum für seltene Netzhauterkrankungen, AugenZentrum Siegburg, MVZ Augenärztliches Diagnostik- und Therapiecentrum Siegburg GmbH, Siegburg, Germany.,RetinaScience, Bonn, Germany
| | | | - Carina Kelbsch
- Centre for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Felix Tonagel
- Centre for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Helmut Wilhelm
- Centre for Ophthalmology, University Eye Hospital, University of Tübingen, Tübingen, Germany
| | - Susanne Kohl
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
| | - Bernd Wissinger
- Institute for Ophthalmic Research, Centre for Ophthalmology, University of Tübingen, Tübingen, Germany
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Formosa LE, Reljic B, Sharpe AJ, Hock DH, Muellner-Wong L, Stroud DA, Ryan MT. Optic atrophy-associated TMEM126A is an assembly factor for the ND4-module of mitochondrial complex I. Proc Natl Acad Sci U S A 2021; 118:e2019665118. [PMID: 33879611 DOI: 10.1073/pnas.2019665118] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Mitochondrial disease is a debilitating condition with a diverse genetic etiology. Here, we report that TMEM126A, a protein that is mutated in patients with autosomal-recessive optic atrophy, participates directly in the assembly of mitochondrial complex I. Using a combination of genome editing, interaction studies, and quantitative proteomics, we find that loss of TMEM126A results in an isolated complex I deficiency and that TMEM126A interacts with a number of complex I subunits and assembly factors. Pulse-labeling interaction studies reveal that TMEM126A associates with the newly synthesized mitochondrial DNA (mtDNA)-encoded ND4 subunit of complex I. Our findings indicate that TMEM126A is involved in the assembly of the ND4 distal membrane module of complex I. In addition, we find that the function of TMEM126A is distinct from its paralogue TMEM126B, which acts in assembly of the ND2-module of complex I.
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8
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D'Angelo L, Astro E, De Luise M, Kurelac I, Umesh-Ganesh N, Ding S, Fearnley IM, Gasparre G, Zeviani M, Porcelli AM, Fernandez-Vizarra E, Iommarini L. NDUFS3 depletion permits complex I maturation and reveals TMEM126A/OPA7 as an assembly factor binding the ND4-module intermediate. Cell Rep 2021; 35:109002. [PMID: 33882309 PMCID: PMC8076766 DOI: 10.1016/j.celrep.2021.109002] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 02/25/2021] [Accepted: 03/25/2021] [Indexed: 11/25/2022] Open
Abstract
Complex I (CI) is the largest enzyme of the mitochondrial respiratory chain, and its defects are the main cause of mitochondrial disease. To understand the mechanisms regulating the extremely intricate biogenesis of this fundamental bioenergetic machine, we analyze the structural and functional consequences of the ablation of NDUFS3, a non-catalytic core subunit. We show that, in diverse mammalian cell types, a small amount of functional CI can still be detected in the complete absence of NDUFS3. In addition, we determine the dynamics of CI disassembly when the amount of NDUFS3 is gradually decreased. The process of degradation of the complex occurs in a hierarchical and modular fashion in which the ND4 module remains stable and bound to TMEM126A. We, thus, uncover the function of TMEM126A, the product of a disease gene causing recessive optic atrophy as a factor necessary for the correct assembly and function of CI.
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Affiliation(s)
- Luigi D'Angelo
- Department of Pharmacy and Biotechnology (FABIT), University of Bologna, 40126 Bologna, Italy
| | - Elisa Astro
- Department of Pharmacy and Biotechnology (FABIT), University of Bologna, 40126 Bologna, Italy
| | - Monica De Luise
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy
| | - Ivana Kurelac
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy
| | - Nikkitha Umesh-Ganesh
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy
| | - Shujing Ding
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, CB2 0XY Cambridge, UK
| | - Ian M Fearnley
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, CB2 0XY Cambridge, UK
| | - Giuseppe Gasparre
- Department of Medical and Surgical Sciences (DIMEC), University of Bologna, 40138 Bologna, Italy; Center for Applied Biomedical Research (CRBA), University of Bologna, 40138 Bologna, Italy
| | - Massimo Zeviani
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, CB2 0XY Cambridge, UK; Venetian Institute of Molecular Medicine, 35128 Padua, Italy; Department of Neurosciences, University of Padua, 35128 Padua, Italy
| | - Anna Maria Porcelli
- Department of Pharmacy and Biotechnology (FABIT), University of Bologna, 40126 Bologna, Italy; Interdepartmental Center of Industrial Research (CIRI) Life Science and Health Technologies, University of Bologna, 40064 Ozzano dell'Emilia, Italy
| | - Erika Fernandez-Vizarra
- Medical Research Council-Mitochondrial Biology Unit, University of Cambridge, CB2 0XY Cambridge, UK; Institute of Molecular, Cell and Systems Biology, University of Glasgow, G12 8QQ Glasgow, UK.
| | - Luisa Iommarini
- Department of Pharmacy and Biotechnology (FABIT), University of Bologna, 40126 Bologna, Italy.
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Fernandez-Vizarra E, Zeviani M. Mitochondrial disorders of the OXPHOS system. FEBS Lett 2020; 595:1062-1106. [PMID: 33159691 DOI: 10.1002/1873-3468.13995] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 10/21/2020] [Accepted: 11/01/2020] [Indexed: 12/13/2022]
Abstract
Mitochondrial disorders are among the most frequent inborn errors of metabolism, their primary cause being the dysfunction of the oxidative phosphorylation system (OXPHOS). OXPHOS is composed of the electron transport chain (ETC), formed by four multimeric enzymes and two mobile electron carriers, plus an ATP synthase [also called complex V (cV)]. The ETC performs the redox reactions involved in cellular respiration while generating the proton motive force used by cV to synthesize ATP. OXPHOS biogenesis involves multiple steps, starting from the expression of genes encoded in physically separated genomes, namely the mitochondrial and nuclear DNA, to the coordinated assembly of components and cofactors building each individual complex and eventually the supercomplexes. The genetic cause underlying around half of the diagnosed mitochondrial disease cases is currently known. Many of these cases result from pathogenic variants in genes encoding structural subunits or additional factors directly involved in the assembly of the ETC complexes. Here, we review the historical and most recent findings concerning the clinical phenotypes and the molecular pathological mechanisms underlying this particular group of disorders.
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Affiliation(s)
- Erika Fernandez-Vizarra
- Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK
| | - Massimo Zeviani
- Venetian Institute of Molecular Medicine, Padova, Italy.,Department of Neurosciences, University of Padova, Italy
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10
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Li JK, Li W, Gao FJ, Qu SF, Hu FY, Zhang SH, Li LL, Wang ZW, Qiu Y, Wang LS, Huang J, Wu JH, Chen F. Mutation Screening of mtDNA Combined Targeted Exon Sequencing in a Cohort With Suspected Hereditary Optic Neuropathy. Transl Vis Sci Technol 2020; 9:11. [PMID: 32855858 PMCID: PMC7422818 DOI: 10.1167/tvst.9.8.11] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 04/23/2020] [Indexed: 12/02/2022] Open
Abstract
Purpose Leber hereditary optic neuropathy (LHON) and autosomal dominant optic atrophy (ADOA) are the two commonest forms of hereditary optic neuropathy. The aim of this study was to comprehensively investigate the incidence and spectrum of mutations in patients with suspected hereditary optic neuropathy by combining mitochondrial DNA (mtDNA) genome-wide and targeted exon sequencing. Methods A cohort of 1101 subjects were recruited to participate in the study, comprising 177 families (177 probands and their family members, a total of 537 subjects, including 254 patients) and 164 sporadic cases with suspected hereditary optic neuropathy, and 400 unrelated control subjects for genetic analysis: all subjects (including control subjects) underwent a comprehensive ophthalmologic examination and were subjected to sequencing analysis of mtDNA genome-wide and targeted exon. Overall, targeted exon sequencing was used to screen 792 genes associated with common hereditary eye diseases, and the mtDNA genome-wide were screened by next-generation sequencing. Results We found variants detected in 168 (40.2%, 168/418) of the 418 patients screened. Among these, 132 cases (78.6%, 132/168) were detected with known LHON disease-causing mtDNA variants; 40 cases (23.8%, 40/168) were detected with nuclear DNA (ntDNA) variants, which included 36 cases (21.4%, 36/168) with detected OPA1 mutations, 4 patients (2.4%, 4/168) with detected OPA3 mutations, and 2 patients (1.2%, 2/168) with detected TMEM126A homozygous mutation. Coexistence variation (mtDNA/mtDNA [n = 16], ntDNA/ntDNA [n = 4], mtDNA/ntDNA [n = 7]) was found in 27 patients (16.4%, 27/165), including mtDNA/ntDNA coexistence variation that was detected in seven patients. Among these ntDNA mutations, 38 distinct disease-causing variants, including autosomal recessive heterozygous mutations, were detected, which included 22 novel variants and two de novo variants. Total haplogroup distribution showed that 34.5% (29/84) and 28.6% (24/84) of the affected subjects with m.11778G>A belonged to haplogroup D and M, with a high frequency of subhaplogroups D4, D5, and M7. Conclusions The LHON-mtDNA mutations are the commonest genetic defects in this Chinese cohort, followed by the OPA1 mutations. To our knowledge, this is the first comprehensive study of LHON, ADOA, and autosomal recessive optic atrophy combined with mtDNA genome-wide and targeted exon sequencing, as well as haplogroup analysis, in a large cohort of Chinese patients with suspected hereditary optic neuropathy. Our findings provide a powerful basis for genetic counseling in patients with suspected hereditary optic neuropathy. Translational Relevance We applied mtDNA genome-wide sequencing combined with panel-based targeted exon sequencing to explore the pathogenic variation spectrum and genetic characteristics of patients with suspected hereditary optic neuropathy, providing a comprehensive research strategy for clinical assistant diagnosis, treatment, and genetic counseling.
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Affiliation(s)
- Jian-Kang Li
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, China.,Department of Computer Science, City University of Hong Kong, Kowloon, Hong Kong.,BGI-Shenzhen, Shenzhen, China
| | - Wei Li
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, China.,BGI-Shenzhen, Shenzhen, China
| | - Feng-Juan Gao
- Eye Institute, Eye, Ear, Nose and Throat Hospital, College of Medicine, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Visual Impairment and Restoration, Science and Technology Commission of Shanghai Municipality, Shanghai, China
| | - Shou-Fang Qu
- National Institutes for Food and Drug Control, Tiantan Xili Dongcheng District, Beijing, China
| | - Fang-Yuan Hu
- Eye Institute, Eye, Ear, Nose and Throat Hospital, College of Medicine, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Visual Impairment and Restoration, Science and Technology Commission of Shanghai Municipality, Shanghai, China
| | - Sheng-Hai Zhang
- Eye Institute, Eye, Ear, Nose and Throat Hospital, College of Medicine, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Visual Impairment and Restoration, Science and Technology Commission of Shanghai Municipality, Shanghai, China
| | - Li-Li Li
- National Institutes for Food and Drug Control, Tiantan Xili Dongcheng District, Beijing, China
| | - Zi-Wei Wang
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, China.,BGI-Shenzhen, Shenzhen, China
| | - Yong Qiu
- BGI-Shenzhen, Shenzhen, China.,MGI, BGI-Shenzhen, Shenzhen, China
| | - Lu-Sheng Wang
- Department of Computer Science, City University of Hong Kong, Kowloon, Hong Kong.,BGI-Shenzhen, Shenzhen, China
| | - Jie Huang
- National Institutes for Food and Drug Control, Tiantan Xili Dongcheng District, Beijing, China
| | - Ji-Hong Wu
- Eye Institute, Eye, Ear, Nose and Throat Hospital, College of Medicine, Fudan University, Shanghai, China.,Shanghai Key Laboratory of Visual Impairment and Restoration, Science and Technology Commission of Shanghai Municipality, Shanghai, China
| | - Fang Chen
- BGI-Shenzhen, Shenzhen, China.,MGI, BGI-Shenzhen, Shenzhen, China
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