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Caron-Godon CA, Collington E, Wolf JL, Coletta G, Glerum DM. More than Just Bread and Wine: Using Yeast to Understand Inherited Cytochrome Oxidase Deficiencies in Humans. Int J Mol Sci 2024; 25:3814. [PMID: 38612624 PMCID: PMC11011759 DOI: 10.3390/ijms25073814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Revised: 03/26/2024] [Accepted: 03/28/2024] [Indexed: 04/14/2024] Open
Abstract
Inherited defects in cytochrome c oxidase (COX) are associated with a substantial subset of diseases adversely affecting the structure and function of the mitochondrial respiratory chain. This multi-subunit enzyme consists of 14 subunits and numerous cofactors, and it requires the function of some 30 proteins to assemble. COX assembly was first shown to be the primary defect in the majority of COX deficiencies 36 years ago. Over the last three decades, most COX assembly genes have been identified in the yeast Saccharomyces cerevisiae, and studies in yeast have proven instrumental in testing the impact of mutations identified in patients with a specific COX deficiency. The advent of accessible genome-wide sequencing capabilities has led to more patient mutations being identified, with the subsequent identification of several new COX assembly factors. However, the lack of genotype-phenotype correlations and the large number of genes involved in generating a functional COX mean that functional studies must be undertaken to assign a genetic variant as being causal. In this review, we provide a brief overview of the use of yeast as a model system and briefly compare the COX assembly process in yeast and humans. We focus primarily on the studies in yeast that have allowed us to both identify new COX assembly factors and to demonstrate the pathogenicity of a subset of the mutations that have been identified in patients with inherited defects in COX. We conclude with an overview of the areas in which studies in yeast are likely to continue to contribute to progress in understanding disease arising from inherited COX deficiencies.
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Affiliation(s)
- Chenelle A. Caron-Godon
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada; (C.A.C.-G.); (E.C.); (J.L.W.); (G.C.)
| | - Emma Collington
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada; (C.A.C.-G.); (E.C.); (J.L.W.); (G.C.)
| | - Jessica L. Wolf
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada; (C.A.C.-G.); (E.C.); (J.L.W.); (G.C.)
| | - Genna Coletta
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada; (C.A.C.-G.); (E.C.); (J.L.W.); (G.C.)
| | - D. Moira Glerum
- Department of Biology, University of Waterloo, Waterloo, ON N2L 3G1, Canada; (C.A.C.-G.); (E.C.); (J.L.W.); (G.C.)
- Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
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Lee IC, Chiang KL. Clinical Diagnosis and Treatment of Leigh Syndrome Based on SURF1: Genotype and Phenotype. Antioxidants (Basel) 2021; 10:antiox10121950. [PMID: 34943053 PMCID: PMC8750222 DOI: 10.3390/antiox10121950] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 11/30/2021] [Accepted: 12/03/2021] [Indexed: 11/17/2022] Open
Abstract
SURF1 encodes the assembly factor for maintaining the antioxidant of cytochrome c oxidase (COX) stability in the human electron respiratory chain. Mutations in SURF1 can cause Leigh syndrome (LS), a subacute neurodegenerative encephalopathy, characterized by early onset (infancy), grave prognosis, and predominant symptoms presenting in the basal ganglia, thalamus, brainstem, cerebellum, and peripheral nerves. To date, more than sixty different SURF1 mutations have been found to cause SURF1-associated LS; however, the relationship between genotype and phenotype is still unclear. Most SURF1-associated LS courses present as typical LS and cause early mortality (before the age of ten years). However, 10% of the cases present with atypical courses with milder symptoms and increased life expectancy. One reason for this inconsistency may be due to specific duplications or mutations close to the C-terminus of the SURF1 protein appearing to cause less protein decay. Furthermore, the treatment for SURF1-associated LS is unsatisfactory. A ketogenic diet is most often prescribed and has proven to be effective. Supplementing with coenzyme Q and other cofactors is also a common treatment option; however, the results are inconsistent. Importantly, anti-epileptic drugs such as valproate—which cause mitochondrial dysfunction—should be avoided in patients with SURF1-associated LS presenting with seizures.
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Affiliation(s)
- Inn-Chi Lee
- Division of Pediatric Neurology, Department of Pediatrics, Chung Shan Medical University Hospital, Taichung 40201, Taiwan
- Institute of Medicine, School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan
- Correspondence: ; Tel.: +886-4-2473-9535; Fax: +886-4-2471-0934
| | - Kuo-Liang Chiang
- Department of Pediatric Neurology, Kuang-Tien General Hospital, Taichung 43303, Taiwan;
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Cytochrome c oxidase deficiency. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1862:148335. [PMID: 33171185 DOI: 10.1016/j.bbabio.2020.148335] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/31/2020] [Accepted: 11/03/2020] [Indexed: 12/23/2022]
Abstract
Cytochrome c oxidase (COX) deficiency is characterized by a high degree of genetic and phenotypic heterogeneity, partly reflecting the extreme structural complexity, multiple post-translational modification, variable, tissue-specific composition, and the high number of and intricate connections among the assembly factors of this enzyme. In fact, decreased COX specific activity can manifest with different degrees of severity, affect the whole organism or specific tissues, and develop a wide spectrum of disease natural history, including disease onsets ranging from birth to late adulthood. More than 30 genes have been linked to COX deficiency, but the list is still incomplete and in fact constantly updated. We here discuss the current knowledge about COX in health and disease, focusing on genetic aetiology and link to clinical manifestations. In addition, information concerning either fundamental biological features of the enzymes or biochemical signatures of its defects have been provided by experimental in vivo models, including yeast, fly, mouse and fish, which expanded our knowledge on the functional features and the phenotypical consequences of different forms of COX deficiency.
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Kose M, Canda E, Kagnici M, Aykut A, Adebali O, Durmaz A, Bircan A, Diniz G, Eraslan C, Kose E, Ünalp A, Yılmaz Ü, Ozyilmaz B, Özdemir TR, Atik T, Uçar SK, McFarland R, Taylor RW, Brown GK, Çoker M, Özkınay F. SURF1 related Leigh syndrome: Clinical and molecular findings of 16 patients from Turkey. Mol Genet Metab Rep 2020; 25:100657. [PMID: 33134083 PMCID: PMC7586243 DOI: 10.1016/j.ymgmr.2020.100657] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/03/2020] [Accepted: 10/03/2020] [Indexed: 01/09/2023] Open
Abstract
Introduction Pathogenic variants in SURF1, a nuclear-encoded gene encoding a mitochondrial chaperone involved in COX assembly, are one of the most common causes of Leigh syndrome (LS). Material-methods Sixteen patients diagnosed to have SURF1-related LS between 2012 and 2020 were included in the study. Their clinical, biochemical and molecular findings were recorded. 10/16 patients were diagnosed using whole-exome sequencing (WES), 4/16 by Sanger sequencing of SURF1, 1/16 via targeted exome sequencing and 1/16 patient with whole-genome sequencing (WGS). The pathogenicity of SURF1 variants was evaluated by phylogenetic studies and modelling on the 3D structure of the SURF1 protein. Results We identified 16 patients from 14 unrelated families who were either homozygous or compound heterozygous for SURF1 pathogenic variants. Nine different SURF1 variants were detected The c.769G > A was the most common variant with an allelic frequency of 42.8% (12/28), c.870dupT [(p.Lys291*); (8/28 28.5%)], c.169delG [(p.Glu57Lysfs*15), (2/24; 7.1%)], c.532 T > A [(p.Tyr178Asn); (2/28, 7.1%)], c.653_654delCT [(p.Pro218Argfs*29); (4/28, 14.2%)] c.595_597delGGA [(p.Gly199del); (1/28, 3.5%)], c.751 + 1G > A (2/28, 4.1%), c.356C > T [(p.Pro119Leu); (2/28, 3.5%)] were the other detected variants. Two pathogenic variants, C.595_597delGGA and c.356C > T, were detected for the first time. The c.769 G > A variant detected in 6 patients from 5 families was evaluated in terms of phenotype-genotype correlation. There was no definite genotype – phenotype correlation. Conclusions To date, more than 120 patients of LS with SURF1 pathogenic variants have been reported. We shared the clinical, molecular data and natural course of 16 new SURF1 defect patients from our country. This study is the first comprehensive research from Turkey that provides information about disease-causing variants in the SURF1 gene. The identification of common variants and phenotype of the SURF1 gene is important for understanding SURF1 related LS. Synopsis SURF1 gene defects are one of the most important causes of LS; patients have a homogeneous clinical and biochemical phenotype.
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Affiliation(s)
- Melis Kose
- Izmir Katip Çelebi University Faculty of Medicine, Department of Pediatrics, Division of Pediatric Metabolism and Nutrition, Izmir, Turkey.,Ege University Faculty of Medicine, Department of Pediatrics, Division of Nutrition and Metabolism, Izmir, Turkey.,Oxford University Hospitals NHS Foundation Trust, The Churchill Hospital, Oxford Medical Genetics Laboratories, Oxford, UK
| | - Ebru Canda
- Ege University Faculty of Medicine, Department of Pediatrics, Division of Nutrition and Metabolism, Izmir, Turkey
| | - Mehtap Kagnici
- University of Health Sciences, Antalya Training and Research Hospital, Department of Pediatrics, Division of Metabolism and Nutrition, Antalya, Turkey
| | - Ayça Aykut
- Ege University Faculty of Medicine, Department of Medical Genetics, Izmir, Turkey
| | - Ogün Adebali
- Sabanci University, Faculty of Engineering and Natural Sciences, Molecular Biology, Genetics and Bioengineering Program, Adebali Lab, Istanbul, Turkey
| | - Asude Durmaz
- Ege University Faculty of Medicine, Department of Medical Genetics, Izmir, Turkey
| | - Aylin Bircan
- Sabanci University, Faculty of Engineering and Natural Sciences, Molecular Biology, Genetics and Bioengineering Program, Adebali Lab, Istanbul, Turkey
| | - Gulden Diniz
- Izmir Democracy University, Faculty of Medicine, Department of Pathology, İzmir, Turkey
| | - Cenk Eraslan
- Ege University Faculty of Medicine, Department of Radiology, Division of Neuroradiology, Izmir, Turkey
| | - Engin Kose
- Ankara University Faculty of Medicine, Department of Pediatrics, Division of Metabolism and Nutrition, Ankara, Turkey
| | - Aycan Ünalp
- University of Health Sciences, Behçet Uz Children Training and Research Hospital, Department of Pediatrics, Division of Neurology, Izmir, Turkey
| | - Ünsal Yılmaz
- University of Health Sciences, Behçet Uz Children Training and Research Hospital, Department of Pediatrics, Division of Neurology, Izmir, Turkey
| | - Berk Ozyilmaz
- University of Health Sciences Tepecik Training and Research Hospital, Department of Medical Genetics, Izmir, Turkey
| | - Taha Reşid Özdemir
- University of Health Sciences Tepecik Training and Research Hospital, Department of Medical Genetics, Izmir, Turkey
| | - Tahir Atik
- Ege University Faculty of Medicine, Department of Pediatrics, Division of Nutrition and Metabolism, Izmir, Turkey
| | - Sema Kalkan Uçar
- Ege University Faculty of Medicine, Department of Pediatrics, Division of Nutrition and Metabolism, Izmir, Turkey
| | - Robert McFarland
- Wellcome Centre for Mitochondrial Research, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Robert W Taylor
- Wellcome Centre for Mitochondrial Research, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Garry K Brown
- Oxford University Hospitals NHS Foundation Trust, The Churchill Hospital, Oxford Medical Genetics Laboratories, Oxford, UK
| | - Mahmut Çoker
- Ege University Faculty of Medicine, Department of Pediatrics, Division of Nutrition and Metabolism, Izmir, Turkey
| | - Ferda Özkınay
- Ege University Faculty of Medicine, Department of Pediatrics, Division of Nutrition and Metabolism, Izmir, Turkey.,University of Health Sciences, Antalya Training and Research Hospital, Department of Pediatrics, Division of Metabolism and Nutrition, Antalya, Turkey
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Maalej M, Kammoun T, Alila-Fersi O, Kharrat M, Ammar M, Felhi R, Mkaouar-Rebai E, Keskes L, Hachicha M, Fakhfakh F. Cytochrome C oxydase deficiency: SURF1 gene investigation in patients with Leigh syndrome. Biochem Biophys Res Commun 2018; 497:1043-1048. [PMID: 29481804 DOI: 10.1016/j.bbrc.2018.02.169] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 02/22/2018] [Indexed: 01/26/2023]
Abstract
Leigh syndrome (LS) is a rare progressive neurodegenerative disorder occurring in infancy. The most common clinical signs reported in LS are growth retardation, optic atrophy, ataxia, psychomotor retardation, dystonia, hypotonia, seizures and respiratory disorders. The paper reported a manifestation of 3 Tunisian patients presented with LS syndrome. The aim of this study is the MT[HYPHEN]ATP6 and SURF1 gene screening in Tunisian patients affected with classical Leigh syndrome and the computational investigation of the effect of detected mutations on its structure and functions by clinical and bioinformatics analyses. After clinical investigations, three Tunisian patients were tested for mutations in both MT-ATP6 and SURF1 genes by direct sequencing followed by in silico analyses to predict the effects of sequence variation. The result of mutational analysis revealed the absence of mitochondrial mutations in MT-ATP6 gene and the presence of a known homozygous splice site mutation c.516-517delAG in sibling patients added to the presence of a novel double het mutations in LS patient (c.752-18 A > C/c. c.751 + 16G > A). In silico analyses of theses intronic variations showed that it could alters splicing processes as well as SURF1 protein translation. Leigh syndrome (LS) is a rare progressive neurodegenerative disorder occurring in infancy. The most common clinical signs reported in LS are growth retardation, optic atrophy, ataxia, psychomotor retardation, dystonia, hypotonia, seizures and respiratory disorders. The paper reported a manifestation of 3 Tunisian patients presented with LS syndrome. The aim of this study is MT-ATP6 and SURF1 genes screening in Tunisian patients affected with classical Leigh syndrome and the computational investigation of the effect of detected mutations on its structure and functions. After clinical investigations, three Tunisian patients were tested for mutations in both MT-ATP6 and SURF1 genes by direct sequencing followed by in silico analysis to predict the effects of sequence variation. The result of mutational analysis revealed the absence of mitochondrial mutations in MT-ATP6 gene and the presence of a known homozygous splice site mutation c.516-517delAG in sibling patients added to the presence of a novel double het mutations in LS patient (c.752-18 A>C/ c.751+16G>A). In silico analysis of theses intronic vaiations showed that it could alters splicing processes as well as SURF1 protein translation.
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Affiliation(s)
- Marwa Maalej
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia.
| | - Thouraya Kammoun
- Service de Pédiatrie, C.H.U. Hedi Chaker, University of Sfax, Tunisia
| | - Olfa Alila-Fersi
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia
| | - Marwa Kharrat
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia
| | - Marwa Ammar
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia
| | - Rahma Felhi
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia
| | - Emna Mkaouar-Rebai
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia
| | - Leila Keskes
- Laboratory of Human Molecular Genetics, Faculty of Medicine of Sfax, University of Sfax, Tunisia
| | - Mongia Hachicha
- Service de Pédiatrie, C.H.U. Hedi Chaker, University of Sfax, Tunisia
| | - Faiza Fakhfakh
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, University of Sfax, Tunisia.
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Emma F, Montini G, Parikh SM, Salviati L. Mitochondrial dysfunction in inherited renal disease and acute kidney injury. Nat Rev Nephrol 2016; 12:267-80. [PMID: 26804019 PMCID: PMC5469549 DOI: 10.1038/nrneph.2015.214] [Citation(s) in RCA: 248] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Mitochondria are increasingly recognized as key players in genetic and acquired renal diseases. Most mitochondrial cytopathies that cause renal symptoms are characterized by tubular defects, but glomerular, tubulointerstitial and cystic diseases have also been described. For example, defects in coenzyme Q10 (CoQ10) biosynthesis and the mitochondrial DNA 3243 A>G mutation are important causes of focal segmental glomerulosclerosis in children and in adults, respectively. Although they sometimes present with isolated renal findings, mitochondrial diseases are frequently associated with symptoms related to central nervous system and neuromuscular involvement. They can result from mutations in nuclear genes that are inherited according to classic Mendelian rules or from mutations in mitochondrial DNA, which are transmitted according to more complex rules of mitochondrial genetics. Diagnosis of mitochondrial disorders involves clinical characterization of patients in combination with biochemical and genetic analyses. In particular, prompt diagnosis of CoQ10 biosynthesis defects is imperative because of their potentially reversible nature. In acute kidney injury (AKI), mitochondrial dysfunction contributes to the physiopathology of tissue injury, whereas mitochondrial biogenesis has an important role in the recovery of renal function. Potential therapies that target mitochondrial dysfunction or promote mitochondrial regeneration are being developed to limit renal damage during AKI and promote repair of injured tissue.
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Affiliation(s)
- Francesco Emma
- Division of Nephrology and Dialysis, Ospedale Pediatrico Bambino Gesù-IRCCS, Piazza Sant'Onofrio 4, 00165 Rome, Italy
| | - Giovanni Montini
- Pediatric Nephrology and Dialysis Unit, Department of Clinical Sciences and Community Health, University of Milan, Fondazione IRCCS Ca' Granda - Ospedale Maggiore Policlinico, Via della Commenda 9, Milano, Italy
| | - Samir M Parikh
- Division of Nephrology and Center for Vascular Biology Research, Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Avenue, Boston, Massachusetts 02215, USA
| | - Leonardo Salviati
- Clinical Genetics Unit, Department of Woman and Child Health, University of Padova, Via Giustiniani 3, 35128, Padova, Italy
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Longo MG, Vairo F, Souza CF, Giugliani R, Vedolin LM. Brain imaging and genetic risk in the pediatric population, part 1: inherited metabolic diseases. Neuroimaging Clin N Am 2015; 25:31-51. [PMID: 25476511 DOI: 10.1016/j.nic.2014.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
In this article, the genotype-MR phenotype correlation of the most common or clinically important inherited metabolic diseases (IMD) in the pediatric population is reviewed. A nonsystematic search of the PubMed/Medline database of relevant studies about "genotype-phenotype correlation" in IMD was performed. Some MR phenotypes related to specific gene mutations were found, such as bilateral hypertrophy of inferior olives in patients harboring POLG and SURF1 mutations, and central lesions in the cervical spinal cord in patients with nonketotic hyperglycinemia harboring GLRX5 gene mutation.
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Affiliation(s)
- Maria Gabriela Longo
- Radiology Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Filippo Vairo
- Medical Genetics Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil; Post Graduation Program on Genetics and Molecular Biology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Carolina Fischinger Souza
- Medical Genetics Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Roberto Giugliani
- Medical Genetics Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil; Department of Genetics, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Leonardo Modesti Vedolin
- Radiology Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil; Post Graduation Program on Medical Sciences: Medicine, Department of Internal Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
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Bosemani T, Anghelescu C, Boltshauser E, Hoon AH, Pearl PL, Craiu D, Johnston MV, Huisman TAGM, Poretti A. Subthalamic nucleus involvement in children: a neuroimaging pattern-recognition approach. Eur J Paediatr Neurol 2014; 18:249-56. [PMID: 24149100 DOI: 10.1016/j.ejpn.2013.09.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 09/17/2013] [Accepted: 09/30/2013] [Indexed: 12/28/2022]
Abstract
A neuroimaging-based pattern-recognition approach has been shown to be very helpful in the diagnosis of a wide range of pediatric central nervous system diseases. Few disorders may selectively affect the subthalamic nucleus in children including Leigh syndrome, succinic semialdehyde dehydrogenase deficiency, kernicterus, chronic end-stage liver failure and near total hypoxic-ischemic injury in the full-term neonates. The consideration of the constellation of clinical history and findings as well as additional neuroimaging findings should allow planning the appropriate diagnostic tests to make the correct diagnosis in children with involvement of the subthalamic nucleus.
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Affiliation(s)
- Thangamadhan Bosemani
- Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | - Eugen Boltshauser
- Department of Pediatric Neurology, University Children's Hospital, Zurich, Switzerland
| | - Alexander H Hoon
- Kennedy Krieger Institute, Baltimore, MD, USA; Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Phillip L Pearl
- Division of Neurology, Children's National Medical Center, Washington, DC, USA
| | - Dana Craiu
- Pediatric Neurology Clinic, Alexandru Obregia Hospital, Bucharest, Romania; Department of Neurology, Pediatric Neurology, Neurosurgery, Psychiatry, "Carol Davila" University of Medicine, Bucharest, Romania
| | - Michael V Johnston
- Kennedy Krieger Institute, Baltimore, MD, USA; Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Thierry A G M Huisman
- Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Andrea Poretti
- Section of Pediatric Neuroradiology, Division of Pediatric Radiology, Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Pediatric Neurology, University Children's Hospital, Zurich, Switzerland.
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Baertling F, Rodenburg RJ, Schaper J, Smeitink JA, Koopman WJH, Mayatepek E, Morava E, Distelmaier F. A guide to diagnosis and treatment of Leigh syndrome. J Neurol Neurosurg Psychiatry 2014; 85:257-65. [PMID: 23772060 DOI: 10.1136/jnnp-2012-304426] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Leigh syndrome is a devastating neurodegenerative disease, typically manifesting in infancy or early childhood. However, also late-onset cases have been reported. Since its first description by Denis Archibald Leigh in 1951, it has evolved from a postmortem diagnosis, strictly defined by histopathological observations, to a clinical entity with indicative laboratory and radiological findings. Hallmarks of the disease are symmetrical lesions in the basal ganglia or brain stem on MRI, and a clinical course with rapid deterioration of cognitive and motor functions. Examinations of fresh muscle tissue or cultured fibroblasts are important tools to establish a biochemical and genetic diagnosis. Numerous causative mutations in mitochondrial and nuclear genes, encoding components of the oxidative phosphorylation system have been described in the past years. Moreover, dysfunctions in pyruvate dehydrogenase complex or coenzyme Q10 metabolism may be associated with Leigh syndrome. To date, there is no cure for affected patients, and treatment options are mostly unsatisfactory. Here, we review the most important clinical aspects of Leigh syndrome, and discuss diagnostic steps as well as treatment options.
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Affiliation(s)
- Fabian Baertling
- Department of General Pediatrics, Neonatology and Pediatric Cardiology, University Children's Hospital, Heinrich-Heine-University, , Düsseldorf, Germany
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Lee IC, El-Hattab AW, Wang J, Li FY, Weng SW, Craigen WJ, Wong LJC. SURF1-associated leigh syndrome: A case series and novel mutations. Hum Mutat 2012; 33:1192-200. [DOI: 10.1002/humu.22095] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2011] [Accepted: 03/15/2012] [Indexed: 11/11/2022]
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Piekutowska-Abramczuk D, Magner M, Popowska E, Pronicki M, Karczmarewicz E, Sykut-Cegielska J, Kmiec T, Jurkiewicz E, Szymanska-Debinska T, Bielecka L, Krajewska-Walasek M, Vesela K, Zeman J, Pronicka E. SURF1 missense mutations promote a mild Leigh phenotype. Clin Genet 2009; 76:195-204. [PMID: 19780766 DOI: 10.1111/j.1399-0004.2009.01195.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
UNLABELLED SURF1 gene mutations are the most common cause of Leigh syndrome (LS), a rare progressive neurodegenerative disorder of infancy, characterized by symmetric necrotizing lesions and hypervascularity in the brainstem and basal ganglia, leading to death before the age of 4 years. Most of the reported mutations create premature termination codons, whereas missense mutations are rare. The aim of the study was to characterize the natural history of LS patients carrying at least one missense mutation in the SURF1 gene. Nineteen such patients (8 own cases and 11 reported in the literature) were compared with a reference group of 20 own c.845_846delCT homozygous patients, and with other LS(SURF-) cases described in the literature. Disease onset in the studied group was delayed. Acute failure to thrive and hyperventilation episodes were rare, respiratory failure did not appear before the age of 4 years. Dystonia, motor regression and eye movement dissociation developed slowly. The number of patients who survived 7 years of life totaled 9 out of 15 (60%) in the 'missense group' and 1 out of 26 (4%) patients with mutations leading to truncated proteins. IN CONCLUSION (i) The presence of a missense mutation in the SURF1 gene may correlate with a milder course and longer survival of Leigh patients, (ii) normal magnetic resonance imaging (MRI) findings, normal blood lactate value, and only mild decrease of cytochrome c oxidase (COX) activity are not sufficient reasons to forego SURF1 mutation analysis in differential diagnosis.
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Abstract
Mitochondrial disorders (MIDs) are an increasingly recognized condition. The second most frequently affected organ in MIDs is the central nervous system. One of the most prevalent clinical CNS manifestations of MIDs is ataxia. Ataxia may be even the dominant manifestation of a MID. This is why certain MIDs should be included in the classification of heredoataxias or at least considered as differentials of classical heredoataxias. MIDs due to mutations of the mitochondrial DNA, which develop ataxia include the MERRF, NARP, MILS, or KSS syndrome. More rarely, ataxia may be a feature of MELAS, LHON, PS, MIDD, or MSL. MIDs due to mutations of the nuclear DNA, which develop ataxia include LS, SANDO, SCAE, AHS, XSLA/A, IOSCA, MIRAS, MEMSA, or LBSL syndrome. More rarely ataxia can be found in AD-CPEO, AR-CPEO, MNGIE, DIDMOAD, CoQ-deficiency, ADOAD, DCMA, or PDC-deficiency. MIDs most frequently associated with ataxia are the non-syndromic MIDs. Syndromic and non-syndromic MIDs with ataxia should be delineated from classical heredoataxias to initiate appropriate symptomatic or supportive treatment.
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Ugalde C, Morán M, Blázquez A, Arenas J, Martín MA. Mitochondrial Disorders Due to Nuclear OXPHOS Gene Defects. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 652:85-116. [DOI: 10.1007/978-90-481-2813-6_7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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14
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Mutation analysis of COX18 in 29 patients with isolated cytochrome c oxidase deficiency. J Hum Genet 2009; 54:419-21. [PMID: 19373256 DOI: 10.1038/jhg.2009.36] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Isolated cytochrome c oxidase (COX) deficiency (MIM#220110) is a relatively common biochemical finding in pediatric patients with mitochondrial disorder. It has been associated with different clinical phenotypes ranging from isolated myopathy to severe multisystem disorder. It is a genetically heterogeneous trait, and the most frequent genetic defects affect SURF1 and SCO2, two genes required for COX assembly. However, a significant proportion of patients lacks mutation in these genes and in other known genes that require COX biogenesis. COX18 is a novel COX assembly gene required for membrane insertion of the C-terminal portion of COX subunit II. We have studied 29 pediatric patients with isolated COX deficiency in the skeletal muscle associated with different clinical phenotypes. Mutations in SURF1, SCO2, SCO1, COX10, COX15 and in mitochondrial DNA, had been ruled out earlier. The COX18 gene was analyzed using a PCR-single-stranded conformation polymorphism (PCR-SSCP) protocol, and in 15 patients, the analysis was repeated by direct sequencing. No pathogenic mutations were detected in our cohort of patients indicating that COX18 mutations may be very rare or associated with other phenotypes than isolated COX deficiency in infancy.
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Piekutowska-Abramczuk D, Popowska E, Pronicki M, Karczmarewicz E, Tylek-Lemanska D, Sykut-Cegielska J, Szymanska-Dembinska T, Bielecka L, Krajewska-Walasek M, Pronicka E. High prevalence of SURF1 c.845_846delCT mutation in Polish Leigh patients. Eur J Paediatr Neurol 2009; 13:146-53. [PMID: 18583168 DOI: 10.1016/j.ejpn.2008.03.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2007] [Revised: 03/12/2008] [Accepted: 03/17/2008] [Indexed: 11/19/2022]
Abstract
Leigh syndrome is a neuropathological disorder with typical morphological changes in brain, appearing regardless of diverse molecular background. One of the most common enzymatic defects in Leigh patients is cytochrome c oxidase deficiency associated with recessive mutations in the SURF1 gene. To assess the SURF1 mutation profile among Polish patients we studied 41 affected children from 34 unrelated families by PCR-SSCP and sequencing. Four novel mutations, c.39delG, c.752-1G>C, c.800_801insT, c.821A>G, and five described pathogenic changes, c.311_312insAT312_321del10, c.688C>T, c.704T>C, c.756_757delCA, c.845_846delCT, were identified in 85.3% of analysed probands. One mutation, c.845_846delCT, was identified in 77.6% of SURF1 alleles. Up to now, it has been reported only in 9% of alleles in other parts of the world. The deletion was used as LS(SURF1-) marker in population studies. Eight heterozygous carriers of the mutation were found in a cohort of 2890 samples. The estimated c.845_846delCT allele frequency is 1:357 (0.28+/-0.2%), and the lowest predicted LS(SURF1-) frequency in Poland 1:126,736.births. Relatively high frequency of LS(SURF1-) in Poland with remarkable c.845_846delCT mutation dominance allows one to start the differential diagnosis of LS in each patient of Polish (and probably Slavonic) origin from the direct search for c.845_846delCT SURF1 mutation.
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Affiliation(s)
- Dorota Piekutowska-Abramczuk
- Department of Medical Genetics, Children's Memorial Health Institute, Al. Dzieci Polskich 20, 04-730 Warsaw, Poland.
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Abstract
Leigh syndrome (also termed subacute, necrotizing encephalopathy) is a devastating neurodegenerative disorder, characterized by almost identical brain changes, e.g., focal, bilaterally symmetric lesions, particularly in the basal ganglia, thalamus, and brainstem, but with considerable clinical and genetic heterogeneity. Clinically, Leigh syndrome is characterized by a wide variety of abnormalities, from severe neurologic problems to a near absence of abnormalities. Most frequently the central nervous system is affected, with psychomotor retardation, seizures, nystagmus, ophthalmoparesis, optic atrophy, ataxia, dystonia, or respiratory failure. Some patients also present with peripheral nervous system involvement, including polyneuropathy or myopathy, or non-neurologic abnormalities, e.g., diabetes, short stature, hypertrichosis, cardiomyopathy, anemia, renal failure, vomiting, or diarrhea (Leigh-like syndrome). In the majority of cases, onset is in early childhood, but in a small number of cases, adults are affected. In the majority of cases, dysfunction of the respiratory chain (particularly complexes I, II, IV, or V), of coenzyme Q, or of the pyruvate dehydrogenase complex are responsible for the disease. Associated mutations affect genes of the mitochondrial or nuclear genome. Leigh syndrome and Leigh-like syndrome are the mitochondrial disorders with the largest genetic heterogeneity.
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Pronicki M, Matyja E, Piekutowska-Abramczuk D, Szymanska-Debinska T, Karkucinska-Wieckowska A, Karczmarewicz E, Grajkowska W, Kmiec T, Popowska E, Sykut-Cegielska J. Light and electron microscopy characteristics of the muscle of patients with SURF1 gene mutations associated with Leigh disease. J Clin Pathol 2007; 61:460-6. [PMID: 17908801 PMCID: PMC2571978 DOI: 10.1136/jcp.2007.051060] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIMS Leigh syndrome (LS) is characterised by almost identical brain changes despite considerable causal heterogeneity. SURF1 gene mutations are among the most frequent causes of LS. Although deficiency of cytochrome c oxidase (COX) is a typical feature of the muscle in SURF1-deficient LS, other abnormalities have been rarely described. The aim of the present work is to assess the skeletal muscle morphology coexisting with SURF1 mutations from our own research and in the literature. METHODS Muscle samples from 21 patients who fulfilled the criteria of LS and SURF1 mutations (14 homozygotes and 7 heterozygotes of c.841delCT) were examined by light and electron microscopy. RESULTS Diffuse decreased activity or total deficit of COX was revealed histochemically in all examined muscles. No ragged red fibres (RRFs) were seen. Lipid accumulation and fibre size variability were found in 14 and 9 specimens, respectively. Ultrastructural assessment showed several mitochondrial abnormalities, lipid deposits, myofibrillar disorganisation and other minor changes. In five cases no ultrastructural changes were found. Apart from slight correlation between lipid accumulation shown by histochemical and ultrastructural techniques, no other correlations were revealed between parameters investigated, especially between severity of morphological changes and the patient's age at the biopsy. CONCLUSION Histological and histochemical features of muscle of genetically homogenous SURF1-deficient LS were reproducible in detection of COX deficit. Minor muscle changes were not commonly present. Also, ultrastructural abnormalities were not a consistent feature. It should be emphasised that SURF1-deficient muscle assessed in the light and electron microscopy panel may be interpreted as normal if COX staining is not employed.
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Affiliation(s)
- M Pronicki
- Department of Pathology, The Children's Memorial Health Institute, Warsaw, Poland.
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Trevisson E, Salviati L, Baldoin MC, Toldo I, Casarin A, Sacconi S, Cesaro L, Basso G, Burlina AB. Argininosuccinate lyase deficiency: mutational spectrum in Italian patients and identification of a novelASLpseudogene. Hum Mutat 2007; 28:694-702. [PMID: 17326097 DOI: 10.1002/humu.20498] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Argininosuccinic aciduria (ASAuria) is an inborn error of metabolism caused by mutations in the argininosuccinate lyase (ASL) gene, which leads to the accumulation of argininosuccinic acid (ASA) in body fluids and severe hyperammonemia. A severe neonatal form and a milder late-onset variant are described. We report a novel ASL pseudogene located in the centromeric region of chromosome 7, 14 novel mutations in the ASL gene, and a novel intronic polymorphism found in a cohort of Italian patients. Our approach relied exclusively on genomic DNA analysis. We found seven missense mutations, two nonsense, three small insertions/deletions, and two splicing mutations. Only two patients harbored previously described mutations, and among the novel variants only two were present in more than one kindred. The pathogenicity of the splicing mutations was demonstrated by a functional splicing assay that employed a hybrid minigene. We also performed molecular modeling using the reported three-dimensional structure of ASL to predict the functional consequences of the missense mutations. There was no genotype-phenotype correlation. Patients with neonatal onset display developmental delay and seizures despite adequate metabolic control. Moreover, hepatomegaly, fibrosis, and abnormal liver function tests are common complications in these patients, but not in patients with the late infancy form. We stress the importance of mutation analysis in patients with ASAuria, to confirm the clinical diagnosis, and to perform DNA-based prenatal diagnosis in future pregnancies of these families.
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Affiliation(s)
- Eva Trevisson
- Department of Pediatrics, University of Padova, Padova, Italy
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Lee HF, Lee HJ, Chi CS, Tsai CR, Chang TK, Wang CJ. The neurological evolution of Pearson syndrome: case report and literature review. Eur J Paediatr Neurol 2007; 11:208-14. [PMID: 17434771 DOI: 10.1016/j.ejpn.2006.12.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2006] [Revised: 12/03/2006] [Accepted: 12/11/2006] [Indexed: 11/30/2022]
Abstract
BACKGROUND Pearson syndrome (PS) is an uncommon specific syndrome among mitochondrial diseases. It has unique clinical presentations. AIMS The purpose of this article is to clarify the neurological evolution, neuroimage findings, molecular genetic analysis and outcomes in PS cases with neurologic manifestations. METHODS We described the clinical progress of a female patient who was diagnosed as PS with a novel 6.0 kbp mitochondrial DNA deletion. She had typical clinical features of PS in early infancy followed by multiple organs involvement after the age of 1 year. At age 3, Kearns-Sayre syndrome (KSS) and Leigh syndrome (LS) developed. We also reviewed PS cases reported in the literature and analyzed the neurological evolution. RESULTS Total 55 PS cases, including our index case, had been reported. Among them, 11 cases had detailed clinical descriptions in terms of hypotonia, developmental delay, ataxia or tremor. In whom, PS might evolve into KSS and/or LS: three cases evolving into KSS; one case on the transition of KSS; three cases evolve into LS; our index case has both presentations. The neuroimage findings of PS were quite different which might be from normal to specific abnormal findings over the cerebral white matter, cerebellum, basal ganglion and brainstem. Among those cases, the molecular analysis revealed large-scale mitochondrial deletion around 3.1-6.0kbp. The outcome of PS was opposite: either early death before age 4 or survived beyond age 7. CONCLUSIONS The neurological features of PS have potential evolution changes that are from normal, mild neurological deficits to special mitochondrial syndromes: KSS and LS. Closely monitoring neurological symptoms, arranging eye fundus examinations and neuroimaging studies in cases with changes of neurological signs are crucial.
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Affiliation(s)
- Hsiu-Fen Lee
- Department of Pediatrics, Taichung Veterans General Hospital, No. 160, Sec. 3 Taichung-Kang Road, Taichung 407, Taiwan, ROC
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Zee JM, Glerum DM. Defects in cytochrome oxidase assembly in humans: lessons from yeast. Biochem Cell Biol 2007; 84:859-69. [PMID: 17215873 DOI: 10.1139/o06-201] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The biogenesis of the inner mitochondrial membrane enzyme cytochrome c oxidase (COX) is a complex process that requires the actions of ancillary proteins, collectively called assembly factors. Studies with the yeast Saccharomyces cerevisiae have provided considerable insight into the COX assembly pathway and have proven to be a fruitful model for understanding the molecular bases for inherited COX deficiencies in humans. In this review, we focus on critical steps in the COX assembly pathway. These processes are conserved from yeast to humans and are known to be involved in the etiology of human COX deficiencies. The contributions from our studies in yeast suggest that this organism remains an excellent model system for delineating the molecular mechanisms underlying COX assembly defects in humans. Current progress suggests that a complete picture of COX assembly will be achieved in the near future.
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Affiliation(s)
- Jennifer M Zee
- Department of Medical Genetics, University of Alberta, Edmonton, AB T6G 0M2, Canada
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Oldfors A, Tulinius M. Mitochondrial encephalomyopathies. HANDBOOK OF CLINICAL NEUROLOGY 2007; 86:125-165. [PMID: 18808998 DOI: 10.1016/s0072-9752(07)86006-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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Abstract
The central nervous system (CNS) is, after the peripheral nervous system, the second most frequently affected organ in mitochondrial disorders (MCDs). CNS involvement in MCDs is clinically heterogeneous, manifesting as epilepsy, stroke-like episodes, migraine, ataxia, spasticity, extrapyramidal abnormalities, bulbar dysfunction, psychiatric abnormalities, neuropsychological deficits, or hypophysial abnormalities. CNS involvement is found in syndromic and non-syndromic MCDs. Syndromic MCDs with CNS involvement include mitochondrial encephalomyopathy, lactacidosis, stroke-like episodes syndrome, myoclonic epilepsy and ragged red fibers syndrome, mitochondrial neuro-gastrointestinal encephalomyopathy syndrome, neurogenic muscle weakness, ataxia, and retinitis pigmentosa syndrome, mitochondrial depletion syndrome, Kearns-Sayre syndrome, and Leigh syndrome, Leber's hereditary optic neuropathy, Friedreich's ataxia, and multiple systemic lipomatosis. As CNS involvement is often subclinical, the CNS including the spinal cord should be investigated even in the absence of overt clinical CNS manifestations. CNS investigations comprise the history, clinical neurological examination, neuropsychological tests, electroencephalogram, cerebral computed tomography scan, and magnetic resonance imaging. A spinal tap is indicated if there is episodic or permanent impaired consciousness or in case of cognitive decline. More sophisticated methods are required if the CNS is solely affected. Treatment of CNS manifestations in MCDs is symptomatic and focused on epilepsy, headache, lactacidosis, impaired consciousness, confusion, spasticity, extrapyramidal abnormalities, or depression. Valproate, carbamazepine, corticosteroids, acetyl salicylic acid, local and volatile anesthetics should be applied with caution. Avoiding certain drugs is often more beneficial than application of established, apparently indicated drugs.
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Affiliation(s)
- J Finsterer
- Krankenanstalt Rudolfstiftung, Vienna, Austria.
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Martella M, Salviati L, Casarin A, Trevisson E, Opocher G, Polli R, Gross D, Murgia A. Molecular analysis of two uncharacterized sequence variants of the VHL gene. J Hum Genet 2006; 51:964-968. [PMID: 17006605 DOI: 10.1007/s10038-006-0054-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2006] [Accepted: 07/30/2006] [Indexed: 10/24/2022]
Abstract
Mutations in the VHL gene cause von Hippel-Lindau disease, a cancer predisposing syndrome characterized by a variety of benign and malignant neoplasms. We report the molecular characterization of two sequence variants of the VHL gene: a synonymous substitution c.462 A>C in exon 2 and a duplication of 11 bp in the promoter region (c.-65_-55dup11). The first variant is a pathogenic mutation because, although it does not change the sense of the affected codon, it causes skipping of exon 2 in the affected allele by altering the splicing consensus site at the 3' end of exon 2. The 11 bp duplication represents a nonpathogenic variant. In fact, although it affects a critical region of the VHL promoter, it was found in healthy controls, and we show that carrier individuals express both VHL alleles at equimolar levels. Our data underline the importance of careful evaluation of the potential pathogenicity of sequence variants that may not belong to the obvious disease-causing mutation categories, or that affect relevant regulatory regions. mRNA analysis will be required to ultimately resolve this issue.
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Affiliation(s)
- Maddalena Martella
- Department of Pediatrics, University of Padova, Via Giustiniani 3, 35128, Padua, Italy
| | - Leonardo Salviati
- Servizio di Genetica Clinica ed Epidemiologica, Department of Pediatrics, University of Padova, Padua, Italy
| | - Alberto Casarin
- Department of Pediatrics, University of Padova, Via Giustiniani 3, 35128, Padua, Italy
| | - Eva Trevisson
- Department of Pediatrics, University of Padova, Via Giustiniani 3, 35128, Padua, Italy
| | - Giuseppe Opocher
- Department of Medical and Surgical Sciences, University of Padua, Padua, Italy
| | - Roberta Polli
- Department of Pediatrics, University of Padova, Via Giustiniani 3, 35128, Padua, Italy
| | - David Gross
- Department of Medicine, Hadassah University Hospital, Jerusalem, Israel
| | - Alessandra Murgia
- Department of Pediatrics, University of Padova, Via Giustiniani 3, 35128, Padua, Italy.
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Yüksel A, Seven M, Cetincelik U, Yeşil G, Köksal V. Facial dysmorphism in Leigh syndrome with SURF-1 mutation and COX deficiency. Pediatr Neurol 2006; 34:486-9. [PMID: 16765830 DOI: 10.1016/j.pediatrneurol.2005.10.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Revised: 09/20/2005] [Accepted: 10/31/2005] [Indexed: 11/19/2022]
Abstract
Leigh syndrome is an inherited, progressive neurodegenerative disorder of infancy and childhood. Mutations in the nuclear SURF-1 gene are specifically associated with cytochrome C oxidase-deficient Leigh syndrome. This report describes two patients with similar facial features. One of them was a 2(1/2)-year-old male, and the other was a 3-year-old male with a mutation in SURF-1 gene and facial dysmorphism including frontal bossing, brachycephaly, hypertrichosis, lateral displacement of inner canthi, esotropia, maxillary hypoplasia, hypertrophic gums, irregularly placed teeth, upturned nostril, low-set big ears, and retrognathi. The first patient's magnetic resonance imaging at 15 months of age indicated mild symmetric T2 prolongation involving the subthalamic nuclei. His second magnetic resonance imaging at 2 years old revealed a symmetric T2 prolongation involving the subthalamic nuclei, substantia nigra, and medulla lesions. In the second child, at the age of 2 the first magnetic resonance imaging documented heavy brainstem and subthalamic nuclei involvement. A second magnetic resonance imaging, performed when he was 3 years old, revealed diffuse involvement of the substantia nigra and hyperintense lesions of the central tegmental tract in addition to previous lesions. Facial dysmorphism and magnetic resonance imaging findings, observed in these cases, can be specific findings in Leigh syndrome patients with cytochrome C oxidase deficiency. SURF-1 gene mutations must be particularly reviewed in such patients.
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Affiliation(s)
- Adnan Yüksel
- Department of Medical Genetic, Division of Pediatric Neurology, Cerrahpaşa Medical Faculty, Istanbul University, Turkey.
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Ostergaard E, Bradinova I, Ravn SH, Hansen FJ, Simeonov E, Christensen E, Wibrand F, Schwartz M. Hypertrichosis in patients withSURF1 mutations. Am J Med Genet A 2005; 138:384-8. [PMID: 16222681 DOI: 10.1002/ajmg.a.30972] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We present three patients with SURF1 mutations. In addition to Leigh syndrome all patients had hypertrichosis, a clinical sign that is not usually associated with Leigh syndrome. The hypertrichosis was not congenital and it was mainly distributed on the extremities and forehead. In addition to our three patients, we have identified five patients in the literature with hypertrichosis and Leigh syndrome due to SURF1 mutations. Since most patients had onset of hypertrichosis before the diagnosis of Leigh syndrome was made, we suggest that clinicians consider Leigh syndrome in patients with, for example, psychomotor retardation or other unspecific symptoms in combination with hypertrichosis.
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