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Rossi M, Wainsztein N, Merello M. Cardiac Involvement in Movement Disorders. Mov Disord Clin Pract 2021; 8:651-668. [PMID: 34307738 DOI: 10.1002/mdc3.13188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 02/23/2021] [Accepted: 03/02/2021] [Indexed: 02/06/2023] Open
Abstract
Background Several conditions represented mainly by movement disorders are associated with cardiac disease, which can be overlooked in clinical practice in the context of a prominent primary neurological disorder. Objectives To review neurological conditions that combine movement disorders and primary cardiac involvement. Methods A comprehensive and structured literature search following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria was conducted to identify disorders combining movement disorders and cardiac disease. Results Some movement disorders are commonly or prominently associated with cardiac disease. Neurological and cardiac symptoms may share underlying physiopathological mechanisms in diseases, such as Friedreich's ataxia and Wilson's disease, and in certain metabolic disorders, including Refsum disease, Gaucher disease, a congenital disorder of glycosylation, or cerebrotendinous xanthomatosis. In certain conditions, such as Sydenham's chorea or dilated cardiomyopathy with ataxia syndrome (ATX-DNAJC19), heart involvement can present early in the course of disease, whereas in others such as Friedreich's ataxia or Refsum disease, cardiac symptoms tend to present in later stages. In another 68 acquired or inherited conditions, cardiac involvement or movement disorders are seldom reported. Conclusions As cardiac disease is part of the phenotypic spectrum of several movement disorders, heart involvement should be carefully investigated and increased awareness of this association encouraged as it may represent a leading cause of morbidity and mortality.
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Affiliation(s)
- Malco Rossi
- Sección Movimientos Anormales, Departamento de Neurociencias Instituto de Investigaciones Neurológicas Raúl Carrea, Fleni Buenos Aires Argentina.,Argentine National Scientific and Technological Research Council Buenos Aires Argentina
| | - Nestor Wainsztein
- Departamento de Medicina Interna Unidad de Cuidados Críticos, Fleni Buenos Aires Argentina
| | - Marcelo Merello
- Sección Movimientos Anormales, Departamento de Neurociencias Instituto de Investigaciones Neurológicas Raúl Carrea, Fleni Buenos Aires Argentina.,Argentine National Scientific and Technological Research Council Buenos Aires Argentina.,Pontificia Universidad Católica Argentina Buenos Aires Argentina
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Bayona-Bafaluy MP, Iglesias E, López-Gallardo E, Emperador S, Pacheu-Grau D, Labarta L, Montoya J, Ruiz-Pesini E. Genetic aspects of the oxidative phosphorylation dysfunction in dilated cardiomyopathy. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2020; 786:108334. [PMID: 33339579 DOI: 10.1016/j.mrrev.2020.108334] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 08/19/2020] [Accepted: 08/20/2020] [Indexed: 12/27/2022]
Abstract
Dilated cardiomyopathy is a frequent and extremely heterogeneous medical condition. Deficits in the oxidative phosphorylation system have been described in patients suffering from dilated cardiomyopathy. Hence, mutations in proteins related to this biochemical pathway could be etiological factors for some of these patients. Here, we review the clinical phenotypes of patients harboring pathological mutations in genes related to the oxidative phosphorylation system, either encoded in the mitochondrial or in the nuclear genome, presenting with dilated cardiomyopathy. In addition to the clinical heterogeneity of these patients, the large genetic heterogeneity has contributed to an improper allocation of pathogenicity for many candidate mutations. We suggest criteria to avoid incorrect assignment of pathogenicity to newly found mutations and discuss possible therapies targeting the oxidative phosphorylation function.
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Affiliation(s)
- M Pilar Bayona-Bafaluy
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain.
| | - Eldris Iglesias
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain.
| | - Ester López-Gallardo
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain.
| | - Sonia Emperador
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain.
| | - David Pacheu-Grau
- Department of Cellular Biochemistry, University Medical Center, Georg-August University,Humboldtalle, 23., 37073, Göttingen, Germany.
| | - Lorenzo Labarta
- Unidad de Cuidados Intensivos, Hospital San Jorge, Av. Martínez de Velasco, 36., 22004, Huesca, Spain.
| | - Julio Montoya
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain.
| | - Eduardo Ruiz-Pesini
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza. C/ Miguel Servet, 177. 50013, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13., 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Red de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain; Fundación ARAID, Av. de Ranillas, 1-D., 50018, Zaragoza, Spain.
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Abstract
BACKGROUND Cardiac abnormalities have been described in patients with Leber hereditary optic neuropathy (LHON). Some are life-threatening because of the risk of ventricular fibrillation and sudden death. The purpose of our study was to better characterize the cardiac abnormalities in a large patient cohort with LHON. METHODS A retrospective study of the electrocardiogram (EKG) results performed on all patients with LHON evaluated at The Reference Center for Rare Diseases in Ophthalmology, Paris, France, from January 2015 to June 2017. RESULTS Our series included 73 patients with LHON (9 women/64 men) with a mean age of 30.29 ± 14.48 years. Although only 1 patient had cardiac complaints, cardiac abnormalities were detected in 17 patients (23.2%): 9 patients had an excitation syndrome, 6 had atrioventricular block, and 2 had repolarization abnormalities. All patients harbored mtDNA point mutations 11778 or 3460. CONCLUSIONS Cardiac abnormalities occur frequently enough in patients with LHON that a baseline EKG is warranted. However, further studies are needed to determine the true cardiac risk associated with specific LHON mtDNA mutations.
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Abstract
Familial dilated cardiomyopathy (F-DCM) describes a clinically and genetically heterogeneous group of diseases, mostly inherited as autosomal dominant traits, having idiopathic left ventricular dilatation and dysfunction as a common phenotype. The age of onset, rate of progression, disease complications, as well as overall prognosis and outcome vary both amongst and within families. Clinical traits, both cardiac and extracardiac, may recur in association with the DCM phenotype. The former include conduction defects, structural abnormalities such as left ventricular noncompaction, of right ventricular involvement, and recurrence of atrial or ventricular arrhythmias; the latter commonly affect the musculoskeletal (myopathies/dystrophies, both clinically overt and subclinical), ocular, auditory, nervous, and integument systems. These traits may help guide genetic testing. In parallel to the clinical heterogeneity, F-DCM also shows genetic heterogeneity: more than 40 genes have been causally linked to F-DCM, with mutations recurring more commonly in a few known genes, and less frequently in rare, less commonly known genes. Based on the known prevalence of mutations in disease genes, more than 50% of F-DCM cases can be regarded as still genetically orphan, implying that further disease genes have to be discovered. Family screening and genetic testing are now established as the gold standard for diagnosis, care, and prevention in F-DCM. Diagnostic tests are performed using Sanger-based sequencing. Furthermore, new biotechnology tools, based on next-generation sequencing, are now being implemented in the research setting and will dramatically modify the future of the nosology of F-DCM.
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Golden AS, Law YM, Shurtleff H, Warner M, Saneto RP. Mitochondrial electron transport chain deficiency, cardiomyopathy, and long-term cardiac transplant outcome. Pediatr Transplant 2012; 16:265-8. [PMID: 22248292 DOI: 10.1111/j.1399-3046.2011.01635.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Organ transplantation in multisystemic mitochondrial cytopathies is usually not performed because of perceived untoward complications. We report three patients with demonstrated oxidative phosphorylation defects and dilated cardiomyopathy who underwent cardiac transplant. All three patients tolerated immunosuppression medications and have had an excellent long-term outcome. Our results suggest that with proper patient selection in this population, cardiac transplantation is feasible and can have good outcomes.
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Affiliation(s)
- Alana S Golden
- Division of Pediatric Neurology, Seattle Children's Hospital and University of Washington, Seattle, WA 98105, USA
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6
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A novel Myosin essential light chain mutation causes hypertrophic cardiomyopathy with late onset and low expressivity. Biochem Res Int 2012; 2012:685108. [PMID: 22957257 PMCID: PMC3432877 DOI: 10.1155/2012/685108] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 02/07/2012] [Indexed: 02/02/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is caused by mutations in genes encoding sarcomere proteins. Mutations in MYL3, encoding the essential light chain of myosin, are rare and have been associated with sudden death. Both recessive and dominant patterns of inheritance have been suggested. We studied a large family with a 38-year-old asymptomatic HCM-affected male referred because of a murmur. The patient had HCM with left ventricular hypertrophy (max WT 21 mm), a resting left ventricular outflow gradient of 36 mm Hg, and left atrial dilation (54 mm). Genotyping revealed heterozygosity for a novel missense mutation, p.V79I, in MYL3. The mutation was not found in 300 controls, and the patient had no mutations in 10 sarcomere genes. Cascade screening revealed a further nine heterozygote mutation carriers, three of whom had ECG and/or echocardiographic abnormalities but did not fulfil diagnostic criteria for HCM. The penetrance, if we consider this borderline HCM the phenotype of the p.V79I mutation, was 40%, but the mean age of the nonpenetrant mutation carriers is 15, while the mean age of the penetrant mutation carriers is 47. The mutation affects a conserved valine replacing it with a larger isoleucine residue in the region of contact between the light chain and the myosin lever arm. In conclusion, MYL3 mutations can present with low expressivity and late onset.
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[Neurology and cardiology: points of contact]. Rev Esp Cardiol 2011; 64:319-27. [PMID: 21411208 DOI: 10.1016/j.recesp.2010.12.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Accepted: 12/10/2010] [Indexed: 01/16/2023]
Abstract
Strokes resulting from cardiac diseases, and cardiac abnormalities associated with neuromuscular disorders are examples of the many points of contact between neurology and cardiology. Approximately 20-30% of strokes are related to cardiac diseases, including atrial fibrillation, congestive heart failure, bacterial endocarditis, rheumatic and nonrheumatic valvular diseases, acute myocardial infarction with left ventricular thrombus, and cardiomyopathies associated with muscular dystrophies, among others. Strokes can also occur in the setting of cardiac interventions such as cardiac catheterization and coronary artery bypass procedures. Treatment to prevent recurrent stroke in any of these settings depends on the underlying etiology. Whereas anticoagulation with vitamin K antagonists is proven to be superior to acetylsalicylic acid for stroke prevention in atrial fibrillation, the superiority of anticoagulants has not been conclusively established for stroke associated with congestive heart failure and is contraindicated in those with infective endocarditis. Ongoing trials are evaluating management strategies in patients with atrial level shunts due to patent foramen ovale. Cardiomyopathies and conduction abnormalities are part of the spectrum of many neuromuscular disorders including mitochondrial disorders and muscular dystrophies. Cardiologists and neurologists share responsibility for caring for patients with or at risk for cardiogenic strokes, and for screening and managing the heart disease associated with neuromuscular disorders.
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Nesbitt V, Whittaker RG, Turnbull DM, McFarland R, Taylor RW. mtDNA disease for the neurologist. FUTURE NEUROLOGY 2011. [DOI: 10.2217/fnl.10.70] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Inherited and acquired mutations of mtDNA cause an extraordinary group of diseases that are associated with a diverse panoply of neurological and non-neurological features. These diseases are surprisingly common and are often severely debilitating and readily transmitted through families. Remarkable advances in understanding molecular mechanisms have been made since the first pathogenic mtDNA mutations were identified in 1988, and while widely available genetic techniques have facilitated diagnosis, the complexities of mitochondrial genetics leave the neurologist facing important challenges in recognizing, managing and counseling patients with mtDNA mutations. In this article, we will discuss the clinical phenotypes associated with mtDNA disease, current diagnostic strategies, disease management and genetic counseling, as well as presenting new developments in preventing disease transmission and secondary complications.
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Affiliation(s)
- Victoria Nesbitt
- Mitochondrial Research Group, Institute for Ageing & Health, The Medical School, Newcastle University, Framlington Place, Newcastle-upon-Tyne, NE2 4HH, UK
| | - Roger G Whittaker
- Mitochondrial Research Group, Institute for Ageing & Health, The Medical School, Newcastle University, Framlington Place, Newcastle-upon-Tyne, NE2 4HH, UK
| | - Douglass M Turnbull
- Mitochondrial Research Group, Institute for Ageing & Health, The Medical School, Newcastle University, Framlington Place, Newcastle-upon-Tyne, NE2 4HH, UK
| | - Robert McFarland
- Mitochondrial Research Group, Institute for Ageing & Health, The Medical School, Newcastle University, Framlington Place, Newcastle-upon-Tyne, NE2 4HH, UK
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Abstract
This is a report of a child who died at 20 months from what was clinically thought to be cardiomyopathy of unknown etiology. Barth syndrome, an X-linked mitochondrial cardioskeletal myopathy, was diagnosed by genetic testing at autopsy. Barth syndrome presents in infancy or childhood with cardiomyopathy, hypotonia, growth delays, and cyclic neutropenia. Other associated laboratory findings can include hypocholesterolemia, relative monocytosis, low prealbumin, low plasma carnitine, and lactic acidosis. The classic echocardiogram finding is left ventricular noncompaction, although not always present. Until recently, the most reliable biochemical finding has been 3-methylglutaconic aciduria. However, quantitative analysis must be specifically requested for results to be reliable. Recently, a confirmatory tetralinoleoyl cardiolipin high-pressure liquid chromotography-tandem mass spectrometry blood test has become available. Genetic testing is also confirmatory and details the underlying mutation. Diagnosis is often missed or delayed and early diagnosis improves survival. The purpose of this case report is to encourage physicians to include Barth syndrome in the differential for cardiomyopathy of uncertain etiology in males, especially in the presence of growth delays, hypotonia, neutropenia, and/or family history of pediatric male death of unknown etiology.
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Affiliation(s)
- Robert T Sweeney
- Department of Pathology and Laboratory Medicine, University of Kentucky College of Medicine, Lexington, KY, USA.
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Haas RH, Parikh S, Falk MJ, Saneto RP, Wolf NI, Darin N, Wong LJ, Cohen BH, Naviaux RK. The in-depth evaluation of suspected mitochondrial disease. Mol Genet Metab 2008; 94:16-37. [PMID: 18243024 PMCID: PMC2810849 DOI: 10.1016/j.ymgme.2007.11.018] [Citation(s) in RCA: 252] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2007] [Revised: 11/21/2007] [Accepted: 11/21/2007] [Indexed: 12/12/2022]
Abstract
Mitochondrial disease confirmation and establishment of a specific molecular diagnosis requires extensive clinical and laboratory evaluation. Dual genome origins of mitochondrial disease, multi-organ system manifestations, and an ever increasing spectrum of recognized phenotypes represent the main diagnostic challenges. To overcome these obstacles, compiling information from a variety of diagnostic laboratory modalities can often provide sufficient evidence to establish an etiology. These include blood and tissue histochemical and analyte measurements, neuroimaging, provocative testing, enzymatic assays of tissue samples and cultured cells, as well as DNA analysis. As interpretation of results from these multifaceted investigations can become quite complex, the Diagnostic Committee of the Mitochondrial Medicine Society developed this review to provide an overview of currently available and emerging methodologies for the diagnosis of primary mitochondrial disease, with a focus on disorders characterized by impairment of oxidative phosphorylation. The aim of this work is to facilitate the diagnosis of mitochondrial disease by geneticists, neurologists, and other metabolic specialists who face the challenge of evaluating patients of all ages with suspected mitochondrial disease.
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Affiliation(s)
- Richard H. Haas
- Departments of Neurosciences & Pediatrics, University of California San Diego, La Jolla, CA and Rady Children's Hospital San Diego, San Diego, CA
- Corresponding Author: Richard H. Haas, MB, BChir, MRCP, Professor of Neurosciences and Pediatrics, University of California San Diego, T. 858-822-6700; F. 858-822-6707;
| | - Sumit Parikh
- Division of Neuroscience, The Cleveland Clinic, Cleveland, OH
| | - Marni J. Falk
- Division of Human Genetics, The Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia, PA
| | - Russell P. Saneto
- Division of Pediatric Neurology, Children's Hospital and Regional Medical Center, University of Washington, Seattle, WA
| | - Nicole I. Wolf
- Department of Child Neurology, University Children's Hospital, Heidelberg, Germany
| | - Niklas Darin
- Division of Child Neurology, The Queen Silvia Children's Hospital, Göteborg, Sweden
| | - Lee-Jun Wong
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Bruce H. Cohen
- Division of Neuroscience, The Cleveland Clinic, Cleveland, OH
| | - Robert K. Naviaux
- Departments of Medicine and Pediatrics, Division of Medical and Biochemical Genetics, University of California San Diego, La Jolla, CA and Rady Children's Hospital San Diego, San Diego, CA
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Exil VJ, Summar M, Boles MA, Atkinson J, Johns JA, Matern D, Strauss AW, Canter CE. Metabolic basis of pediatric heart disease. PROGRESS IN PEDIATRIC CARDIOLOGY 2005. [DOI: 10.1016/j.ppedcard.2005.04.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
Cells of the thyroid tissue, either diseased or normal, can accumulate altered mitochondrial genomes in primary lesions and in surrounding parenchyma. Depending on the experimental approaches and the extent of the mutational process, it has been possible to demonstrate the occurrence of homoplasmic or heteroplasmic point mutations, presence of a common deletion and random large-scale mtDNA aberrations in various pathological states. Point somatic mutations documented in 5-60% of thyroid tumors do not concentrate in obvious hotspots but tend to cluster in certain regions of the mitochondrial genome and their distribution may differ between carcinomas and controls. Large-scale deletions in mtDNA are quite prevalent in healthy and diseased thyroid; however, the proportion of aberrant mtDNA molecules accounts for a very small part of total mtDNA and does not seem to correlate with pathological characteristics of thyroid tumors. Common deletion is most abundant in Hurthle cell tumors, yet it also occurs in other thyroid diseases as well as in normal tissue. The principal difference between the common deletion and other deletion-type mtDNA molecules is that the former does not depend on the relative mtDNA content in the tissue whereas in a subset of thyroid tumors, such as radiation-associated papillary carcinomas and follicular adenomas, there is a strong correlation between mtDNA levels and prevalence of large-scale deletions. Relative mtDNA levels by themselves are elevated in most thyroid tumors compared to normal tissue. Distinct differential distribution and prevalence of mutational mtDNA burden in normal tissue and thyroid lesions are suggestive of the implication of altered mtDNA in thyroid diseases, especially in cancer.
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Affiliation(s)
- Tatiana Rogounovitch
- Department of Molecular Medicine, Graduate School of Biomedical Sciences, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
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Monticelli A, Giacchetti M, De Biase I, Pianese L, Turano M, Pandolfo M, Cocozza S. New clues on the origin of the Friedreich ataxia expanded alleles from the analysis of new polymorphisms closely linked to the mutation. Hum Genet 2004; 114:458-63. [PMID: 14767759 DOI: 10.1007/s00439-004-1089-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2003] [Accepted: 01/09/2004] [Indexed: 10/26/2022]
Abstract
Friedreich's ataxia (FRDA) is an autosomal recessive neurodegenerative disorder commonly caused by large expansions of a GAA repeat in the first intron of the frataxin gene, FRDA. The expansion of the triplet repeat is localized within an Alu sequence. FRDA GAA-repeat alleles can be divided into three classes depending on their lengths: short normal alleles (SN), long normal alleles (LN) and expanded pathological alleles (E). We made an accurate analysis of the Alu sequence containing the GAA repeat. We found a new single-nucleotide polymorphism (SNP) that is the closest one to the GAA repeat. We studied this new SNP and the polymorphic polyA region contiguous to the GAA triplets in two populations with different frequencies of FRDA. We found that, while both E and LN alleles seem to be genetically homogeneous and likely related, SN represents a more heterogeneous class of alleles. Indeed, one SNP variation (T) was more frequently associated with (GAA)(8) alleles, whereas the other one (C) with (GAA)(9) repeat(s). The long normal and expanded alleles presented the C haplotype. The same correlation was described for polyA-tract polymorphisms. Thus, 14A was commonly associated with (GAA)(8) alleles and 17A with (GAA)(9) alleles. The long normal alleles more frequently showed the 17A haplotype. Our data seem to suggest that all the E alleles come from LN alleles, while LN alleles come from a defined subclass of SN alleles.
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Affiliation(s)
- Antonella Monticelli
- Dipartimento di Biologia e Patologia Cellulare e Molecolare, L. Califano Università Federico II, Via S. Pansini 5, 80131 Naples, Italy
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