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Lee CL, Chuang CK, Chiu HC, Chang YH, Tu YR, Lo YT, Lin HY, Lin SP. Application of whole exome sequencing in the diagnosis of muscular disorders: a study of Taiwanese pediatric patients. Front Genet 2024; 15:1365729. [PMID: 38818036 PMCID: PMC11137626 DOI: 10.3389/fgene.2024.1365729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 04/23/2024] [Indexed: 06/01/2024] Open
Abstract
Background Muscular dystrophies and congenital myopathies encompass various inherited muscular disorders that present diagnostic challenges due to clinical complexity and genetic heterogeneity. Methods This study aimed to investigate the use of whole exome sequencing (WES) in diagnosing muscular disorders in pediatric patients in Taiwan. Out of 161 pediatric patients suspected to have genetic/inherited myopathies, 115 received a molecular diagnosis through conventional tests, single gene testing, and gene panels. The remaining 46 patients were divided into three groups: Group 1 (multiplex ligation-dependent probe amplification-negative Duchenne muscular dystrophy) with three patients (6.5%), Group 2 (various forms of muscular dystrophies) with 21 patients (45.7%), and Group 3 (congenital myopathies) with 22 patients (47.8%). Results WES analysis of these groups found pathogenic variants in 100.0% (3/3), 57.1% (12/21), and 68.2% (15/22) of patients in Groups 1 to 3, respectively. WES had a diagnostic yield of 65.2% (30 patients out of 46), detecting 30 pathogenic or potentially pathogenic variants across 28 genes. Conclusion WES enables the diagnosis of rare diseases with symptoms and characteristics similar to congenital myopathies and muscular dystrophies, such as muscle weakness. Consequently, this approach facilitates targeted therapy implementation and appropriate genetic counseling.
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Affiliation(s)
- Chung-Lin Lee
- Department of Pediatrics, MacKay Memorial Hospital, Taipei, Taiwan
- Institute of Clinical Medicine, National Yang-Ming Chiao-Tung University, Taipei, Taiwan
- Department of Rare Disease Center, MacKay Memorial Hospital, Taipei, Taiwan
- Department of Medicine, Mackay Medical College, Taipei, Taiwan
- Mackay Junior College of Medicine, Nursing and Management, Taipei, Taiwan
| | - Chih-Kuang Chuang
- Division of Genetics and Metabolism, Department of Medical Research, MacKay Memorial Hospital, Taipei, Taiwan
- College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan
| | - Huei-Ching Chiu
- Department of Pediatrics, MacKay Memorial Hospital, Taipei, Taiwan
| | - Ya-Hui Chang
- Department of Pediatrics, MacKay Memorial Hospital, Taipei, Taiwan
- Department of Rare Disease Center, MacKay Memorial Hospital, Taipei, Taiwan
| | - Yuan-Rong Tu
- Division of Genetics and Metabolism, Department of Medical Research, MacKay Memorial Hospital, Taipei, Taiwan
| | - Yun-Ting Lo
- Department of Rare Disease Center, MacKay Memorial Hospital, Taipei, Taiwan
| | - Hsiang-Yu Lin
- Department of Pediatrics, MacKay Memorial Hospital, Taipei, Taiwan
- Department of Rare Disease Center, MacKay Memorial Hospital, Taipei, Taiwan
- Department of Medicine, Mackay Medical College, Taipei, Taiwan
- Mackay Junior College of Medicine, Nursing and Management, Taipei, Taiwan
- Division of Genetics and Metabolism, Department of Medical Research, MacKay Memorial Hospital, Taipei, Taiwan
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan
| | - Shuan-Pei Lin
- Department of Pediatrics, MacKay Memorial Hospital, Taipei, Taiwan
- Department of Rare Disease Center, MacKay Memorial Hospital, Taipei, Taiwan
- Department of Medicine, Mackay Medical College, Taipei, Taiwan
- Division of Genetics and Metabolism, Department of Medical Research, MacKay Memorial Hospital, Taipei, Taiwan
- Department of Infant and Child Care, National Taipei University of Nursing and Health Sciences, Taipei, Taiwan
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Piñeros-Fernández MC, Morte B, García-Giménez JL. Utility of exome sequencing for the diagnosis of pediatric-onset neuromuscular diseases beyond diagnostic yield: a narrative review. Neurol Sci 2024; 45:1455-1464. [PMID: 37989827 PMCID: PMC10942921 DOI: 10.1007/s10072-023-07210-z] [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: 09/26/2023] [Accepted: 11/15/2023] [Indexed: 11/23/2023]
Abstract
Diagnosis of neuromuscular diseases (NMD) can be challenging because of the heterogeneity of this group of diseases. This review aimed to describe the diagnostic yield of whole exome sequencing (WES) for pediatric-onset neuromuscular disease diagnosis, as well as other benefits of this approach in patient management since WES can contribute to appropriate treatment selection in NMD patients. WES increases the possibility of reaching a conclusive genetic diagnosis when other technologies have failed and even exploring new genes not previously associated with a specific NMD. Moreover, this strategy can be useful when a dual diagnosis is suspected in complex congenital anomalies and undiagnosed cases.
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Affiliation(s)
- Martha Cecilia Piñeros-Fernández
- Servicio de Neurología Pediátrica, Hospital Pediátrico, Fundación Cardio Infantil-LaCardio, Bogotá, Colombia
- Unidad Pediátrica, Los Cobos Medical Center, Bogotá, Colombia
- Consulta Externa Especializada, Virrey Solís IPS, Bogotá, Colombia
| | - Beatriz Morte
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - José Luis García-Giménez
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.
- Instituto de Investigación Sanitaria INCLIVA, Valencia, Spain.
- Departamento de Fisiología, Facultad de Medicina y Odontología, Universitat de València, València, Spain.
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Summa S, Ittiwut C, Kulsirichawaroj P, Paprad T, Likasitwattanakul S, Sanmaneechai O, Boonsimma P, Suphapeetiporn K, Shotelersuk V. Utilisation of exome sequencing for muscular disorders in Thai paediatric patients: diagnostic yield and mutational spectrum. Sci Rep 2023; 13:1376. [PMID: 36697461 PMCID: PMC9876991 DOI: 10.1038/s41598-023-28405-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 01/18/2023] [Indexed: 01/27/2023] Open
Abstract
Muscular dystrophies and congenital myopathies are heterogeneous groups of inherited muscular disorders. An accurate diagnosis is challenging due to their complex clinical presentations and genetic heterogeneity. This study aimed to determine the utilisation of exome sequencing (ES) for Thai paediatric patients with muscular disorders. Of 176 paediatric patients suspected of genetic/inherited myopathies, 133 patients received a molecular diagnosis after performing conventional investigations, single gene testing, and gene panels. The remaining 43 patients from 42 families could be classified into three groups: Group 1, MLPA-negative Duchenne muscular dystrophy (DMD) with 9 patients (9/43; 21%), Group 2, other muscular dystrophies (MD) with 18 patients (18/43; 42%) and Group 3, congenital myopathies (CM) with 16 patients (16/43; 37%). All underwent exome sequencing which could identify pathogenic variants in 8/9 (89%), 14/18 (78%), and 8/16 (50%), for each Group, respectively. Overall, the diagnostic yield of ES was 70% (30/43) and 36 pathogenic/likely pathogenic variants in 14 genes were identified. 18 variants have never been previously reported. Molecular diagnoses provided by ES changed management in 22/30 (73%) of the patients. Our study demonstrates the clinical utility and implications of ES in inherited myopathies.
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Affiliation(s)
- Sarinya Summa
- Department of Paediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.,Department of Paediatrics, Samutprakan Hospital, Samutprakan, 10270, Thailand
| | - Chupong Ittiwut
- Center of Excellence for Medical Genomics, Medical Genomics Cluster, Department of Paediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, 10330, Thailand
| | - Pimchanok Kulsirichawaroj
- Department of Paediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.,Department of Paediatrics, Faculty of Medicine Vajira Hospital, Navamindradhiraj University, Bangkok, 10300, Thailand
| | - Tanitnun Paprad
- Division of Neurology, Department of Paediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Surachai Likasitwattanakul
- Department of Paediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand
| | - Oranee Sanmaneechai
- Department of Paediatrics, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand.
| | - Ponghatai Boonsimma
- Center of Excellence for Medical Genomics, Medical Genomics Cluster, Department of Paediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand. .,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, 10330, Thailand.
| | - Kanya Suphapeetiporn
- Center of Excellence for Medical Genomics, Medical Genomics Cluster, Department of Paediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, 10330, Thailand
| | - Vorasuk Shotelersuk
- Center of Excellence for Medical Genomics, Medical Genomics Cluster, Department of Paediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, 10330, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, the Thai Red Cross Society, Bangkok, 10330, Thailand
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4
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Genetic Analysis of Forty MLPA-Negative Duchenne Muscular Dystrophy Patients by Whole-Exome Sequencing. J Mol Neurosci 2022; 72:1098-1107. [PMID: 35218518 DOI: 10.1007/s12031-022-01980-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Accepted: 01/26/2022] [Indexed: 10/19/2022]
Abstract
This manuscript aimed to determine the underlying point mutations causing Duchenne muscular dystrophy (DMD) in a heterogeneous group of Iranian patients, who are clinically suspected. Whole-exome sequencing was utilized to detect disease-causing variants in 40 MLPA-negative DMD patients. Disease-causing variants were detected in the DMD gene in 36/40 of the patients (90%), and 4/40 of them (10%) remained undiagnosed. WES analysis revealed that nonsense variant was the most common type in our study (23/36 of the cases). Besides, 12/36 of the cases had frameshift variant, and one of the patients had a likely pathogenic splice variant in the DMD gene. Carrier testing revealed that 21/40 of the mothers had the identified variant. Therefore, most variants were inherited (58.3%), while 19/40 were de novo (41. 7%). The present study has demonstrated the importance of performing WES to detect disease-causing point mutations in MLPA-negative DMD patients and to identify carrier females. Due to regulatory challenges, the clinical development of therapeutic approaches is time-consuming and may not be available to all patients shortly. Therefore, it appears that the techniques used to accurately detect disease-causing variants in carrier mothers are a more efficient solution to prevent the increased prevalence of DMD.
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Zehravi M, Wahid M, Ashraf J, Fatima T. Whole-Exome Sequencing Identifies Small Mutations in Pakistani Muscular Dystrophy Patients. Genet Test Mol Biomarkers 2021; 25:218-226. [PMID: 33734897 DOI: 10.1089/gtmb.2020.0246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Background: Muscular dystrophies are a heterogeneous group of inherited disorders that cannot be diagnosed clinically due to overlapping clinical phenotypes. Whole-exome sequencing is considered as the diagnostic strategy of choice in these cases. In this study we aimed to determine the mutational spectrum of multiplex ligation-dependent probe amplification (MLPA)-negative muscular dystrophy patients in Pakistan using whole-exome sequencing. Subsequently the mutations identified via WES were used to screen additional dystrophinopathy patients by Sanger sequencing. Materials and Methods: DNA extracted from the peripheral blood of three MLPA-negative muscular dystrophy patients was sent for whole-exome sequencing. The identified variants in these 3 patients were then checked in 18 dystrophinopathy patients using Sanger sequencing. Results: Four missense variants and one nonsense variant in the Duchenne muscular dystrophy (DMD) gene were detected. WES diagnosed a DMD patient carrying a nonsense variant c.4375C>T (rs398123953) who can benefit from Ataluren therapy. The other two patients carried missense variant (c.572G>T) in the YARS2 gene (rs11539445) labeling them as patients of MLASA (myopathy, lactic acidosis, and sideroblastic anemia). The identified missense and nonsense variants in the DMD gene were detected in 18 clinically diagnosed dystrophinopathy patients using Sanger sequencing. Three missense variants were detected in our cohort of 18 dystrophinopathy patients. One missense variant c.3406A>T (rs3827462) and a nonsense variant c.4375C>T (rs398123953) were not detected in our cohort of 18 dystrophinopathy patients. Conclusions: Whole-exome sequencing identified a nonsense variant in Pakistani muscular dystrophy patients, which is amenable to treatment by Ataluren and a missense variant in YARS2 gene responsible for causing MLASA.
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Affiliation(s)
- Mehwish Zehravi
- Dow Research Institute of Biotechnology and Biomedical Sciences, Dow University of Health Sciences, Karachi, Pakistan
| | - Mohsin Wahid
- Dow Research Institute of Biotechnology and Biomedical Sciences, Dow University of Health Sciences, Karachi, Pakistan.,Department of Pathology, Dow International Medical College, Dow University of Health Sciences, Karachi, Pakistan
| | - Junaid Ashraf
- Department of Neurosurgery, Dow University of Health Sciences, Karachi, Pakistan
| | - Tehseen Fatima
- Dow Research Institute of Biotechnology and Biomedical Sciences, Dow University of Health Sciences, Karachi, Pakistan.,Dow College of Biotechnology, Dow University of Health Sciences, Karachi, Pakistan
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Zimowski JG, Purzycka J, Pawelec M, Ozdarska K, Zaremba J. Small mutations in Duchenne/Becker muscular dystrophy in 164 unrelated Polish patients. J Appl Genet 2021; 62:289-295. [PMID: 33420945 DOI: 10.1007/s13353-020-00605-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 12/09/2020] [Accepted: 12/22/2020] [Indexed: 10/22/2022]
Abstract
In the 164 patients with Duchenne/Becker muscular dystrophy, we found 142 different small mutations including 51 novel mutations not listed in the LOVD, the UMD-DMD, the ClinVar, and the HGMD databases. Among all mutations, nonsense mutations occurred in 45.7%, frameshift mutations in 32.9%, and splicing mutations in 19.5%. Small mutations were distributed throughout the whole dystrophin gene. Splicing mutations were twice more common in BMD patients than in DMD patients. Eighty-two percent of mothers of the males affected with DMD/BMD were found to be carriers of small mutations.
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Affiliation(s)
- Janusz G Zimowski
- Department of Genetics, Institute of Psychiatry and Neurology, 02-957, Sobieskiego 9, Warsaw, Poland. .,, Warsaw, Poland.
| | - Joanna Purzycka
- Department of Genetics, Institute of Psychiatry and Neurology, 02-957, Sobieskiego 9, Warsaw, Poland
| | - Magdalena Pawelec
- Department of Genetics, Institute of Psychiatry and Neurology, 02-957, Sobieskiego 9, Warsaw, Poland
| | - Katarzyna Ozdarska
- Department of Genetics, Institute of Psychiatry and Neurology, 02-957, Sobieskiego 9, Warsaw, Poland
| | - Jacek Zaremba
- Department of Genetics, Institute of Psychiatry and Neurology, 02-957, Sobieskiego 9, Warsaw, Poland
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Sheikh O, Yokota T. Advances in Genetic Characterization and Genotype-Phenotype Correlation of Duchenne and Becker Muscular Dystrophy in the Personalized Medicine Era. J Pers Med 2020; 10:E111. [PMID: 32899151 PMCID: PMC7565713 DOI: 10.3390/jpm10030111] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 08/30/2020] [Accepted: 09/01/2020] [Indexed: 12/18/2022] Open
Abstract
Currently, Duchenne muscular dystrophy (DMD) and the related condition Becker muscular dystrophy (BMD) can be usually diagnosed using physical examination and genetic testing. While BMD features partially functional dystrophin protein due to in-frame mutations, DMD largely features no dystrophin production because of out-of-frame mutations. However, BMD can feature a range of phenotypes from mild to borderline DMD, indicating a complex genotype-phenotype relationship. Despite two mutational hot spots in dystrophin, mutations can arise across the gene. The use of multiplex ligation amplification (MLPA) can easily assess the copy number of all exons, while next-generation sequencing (NGS) can uncover novel or confirm hard-to-detect mutations. Exon-skipping therapy, which targets specific regions of the dystrophin gene based on a patient's mutation, is an especially prominent example of personalized medicine for DMD. To maximize the benefit of exon-skipping therapies, accurate genetic diagnosis and characterization including genotype-phenotype correlation studies are becoming increasingly important. In this article, we present the recent progress in the collection of mutational data and optimization of exon-skipping therapy for DMD/BMD.
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Affiliation(s)
- Omar Sheikh
- Department of Medical Genetics, University of Alberta Faculty of Medicine and Dentistry, Edmonton, AB T6G 2H7, Canada;
| | - Toshifumi Yokota
- Department of Medical Genetics, University of Alberta Faculty of Medicine and Dentistry, Edmonton, AB T6G 2H7, Canada;
- The Friends of Garrett Cumming Research & Muscular Dystrophy Canada HM Toupin Neurological Science Research Chair, Edmonton, AB T6G 2H7, Canada
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EMQN best practice guidelines for genetic testing in dystrophinopathies. Eur J Hum Genet 2020; 28:1141-1159. [PMID: 32424326 PMCID: PMC7608854 DOI: 10.1038/s41431-020-0643-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 03/03/2020] [Accepted: 04/28/2020] [Indexed: 02/04/2023] Open
Abstract
Dystrophinopathies are X-linked diseases, including Duchenne muscular dystrophy and Becker muscular dystrophy, due to DMD gene variants. In recent years, the application of new genetic technologies and the availability of new personalised drugs have influenced diagnostic genetic testing for dystrophinopathies. Therefore, these European best practice guidelines for genetic testing in dystrophinopathies have been produced to update previous guidelines published in 2010.These guidelines summarise current recommended technologies and methodologies for analysis of the DMD gene, including testing for deletions and duplications of one or more exons, small variant detection and RNA analysis. Genetic testing strategies for diagnosis, carrier testing and prenatal diagnosis (including non-invasive prenatal diagnosis) are then outlined. Guidelines for sequence variant annotation and interpretation are provided, followed by recommendations for reporting results of all categories of testing. Finally, atypical findings (such as non-contiguous deletions and dual DMD variants), implications for personalised medicine and clinical trials and incidental findings (identification of DMD gene variants in patients where a clinical diagnosis of dystrophinopathy has not been considered or suspected) are discussed.
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Predominance of Dystrophinopathy Genotypes in Mexican Male Patients Presenting as Muscular Dystrophy with A Normal Multiplex Polymerase Chain Reaction DMD Gene Result: A Study Including Targeted Next-Generation Sequencing. Genes (Basel) 2019; 10:genes10110856. [PMID: 31671740 PMCID: PMC6895915 DOI: 10.3390/genes10110856] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/23/2019] [Accepted: 10/24/2019] [Indexed: 01/02/2023] Open
Abstract
The complete mutational spectrum of dystrophinopathies and limb-girdle muscular dystrophy (LGMD) remains unknown in Mexican population. Seventy-two unrelated Mexican male patients (73% of pediatric age) with clinical suspicion of muscular dystrophy and no evidence of DMD gene deletion on multiplex polymerase chain reaction (mPCR) analysis were analyzed by multiplex ligation-dependent probe amplification (MLPA). Those with a normal result were subjected to Sanger sequencing or to next-generation sequencing for DMD plus 10 selected LGMD-related genes. We achieved a diagnostic genotype in 80.5% (n = 58/72) of patients with predominance of dystrophinopathy-linked genotypes (68%, n = 49/72), followed by autosomal recessive LGMD-related genotypes (types 2A-R1, 2C-R5, 2E-R4, 2D-R3 and 2I-R9; 12.5%, n = 9/72). MLPA showed 4.2% of false-negatives for DMD deletions assessed by mPCR. Among the small DMD variants, 96.5% (n = 28/29) corresponded to null-alleles, most of which (72%) were inherited through a carrier mother. The FKRP p.[Leu276Ile]; [Asn463Asp] genotype is reported for the first time in Mexican patients as being associated with dilated cardiomyopathy. Absence of dysferlinopathies could be related to the small sample size and/or the predominantly pediatric age of patients. The employed strategy seems to be an affordable diagnosis approach for Mexican muscular dystrophy male patients and their families.
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Wang D, Gao M, Zhang K, Jin R, Lv Y, Liu Y, Ma J, Wan Y, Gai Z, Liu Y. Molecular Genetics Analysis of 70 Chinese Families With Muscular Dystrophy Using Multiplex Ligation-Dependent Probe Amplification and Next-Generation Sequencing. Front Pharmacol 2019; 10:814. [PMID: 31404137 PMCID: PMC6669794 DOI: 10.3389/fphar.2019.00814] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 06/24/2019] [Indexed: 12/12/2022] Open
Abstract
Background: Muscular dystrophy (MD) includes multiple types, of which dystrophinopathies caused by dystrophin (DMD) mutations are the most common types in children. An accurate identification of the causative mutation at the genomic level is critical for genetic counseling of the family, and analysis of genotype-phenotype correlations, as well as a reference for the development of gene therapy. Methods: Totally, 70 Chinese families with suspected MD probands were enrolled in the study. The multiplex ligation-dependent probe amplification (MLPA) was first performed to screen large deletions/duplications of DMD exons in the patients, and then, next-generation sequencing (NGS) was carried out to detect small mutations in the MLPA-negative patients. Results: Totally, 62 mutations of DMD were found in 62 probands with DMD/BMD, and two compound heterozygous mutations in LAMA2 were identified in two probands with MDC1A (a type of congenital MD), indicating that the diagnostic yield was 91.4% by MLPA plus NGS for MD diagnosis in this cohort. Out of the mutations, 51 large mutations encompassing 47 (75.8%) deletions and four duplications (6.5%) were identified by MLPA; 11 small mutations including six (9.7%) nonsense, two (3.2%) small deletions, two splice-site mutations (3.2%), and one small insertion (1.6%) were found by NGS. Large mutations were found most frequently in the hotspot region between exons 45 and 55 (70.6%). Out of the 11 patients harboring point mutations in DMD, 8 were novel mutations. Additionally, one novel mutation in LAMA2 was identified. All the novel mutations were analyzed and predicted as pathogenic according to American College of Medical Genetics and Genomics (ACMG) guideline. Finally, 34 DMD, 4 BMD, 24 BMD/DMD, and 2 MDC1A were diagnosed in the cohort. Conclusion: Our data indicated that the MLPA plus NGS can be a comprehensive and effective tool for precision diagnosis and potential treatment of MD and is particularly necessary for the patients at very young age with only two clinical indicators (persistent hyperCKemia and typical myopathy performance on electromyogram) but no definite clinical manifestations.
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Affiliation(s)
- Dong Wang
- Pediatric Research Institute, Qilu Children’s Hospital, Shandong University, Ji’nan, China
| | - Min Gao
- Pediatric Research Institute, Qilu Children’s Hospital, Shandong University, Ji’nan, China
| | - Kaihui Zhang
- Pediatric Research Institute, Qilu Children’s Hospital, Shandong University, Ji’nan, China
| | - Ruifeng Jin
- Neurology Department, Qilu Children’s Hospital, Shandong University, Ji’nan, China
| | - Yuqiang Lv
- Pediatric Research Institute, Qilu Children’s Hospital, Shandong University, Ji’nan, China
| | - Yong Liu
- Neurology Department, Qilu Children’s Hospital, Shandong University, Ji’nan, China
| | - Jian Ma
- Pediatric Research Institute, Qilu Children’s Hospital, Shandong University, Ji’nan, China
| | - Ya Wan
- Pediatric Research Institute, Qilu Children’s Hospital, Shandong University, Ji’nan, China
| | - Zhongtao Gai
- Pediatric Research Institute, Qilu Children’s Hospital, Shandong University, Ji’nan, China
| | - Yi Liu
- Pediatric Research Institute, Qilu Children’s Hospital, Shandong University, Ji’nan, China
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Cotignola J, Rozental S, Buzzalino N, Dain L. Genetics and genomic medicine in Argentina. Mol Genet Genomic Med 2019; 7:e00571. [PMID: 30724040 PMCID: PMC6465649 DOI: 10.1002/mgg3.571] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 12/31/2018] [Indexed: 11/09/2022] Open
Abstract
In this letter, we want to add information to the paper "Genetics and genomic medicine in Argentina" that we considered it was lacking. Argentina is a big country with inequalities in the access to public health care, especially in medical genetics and genomics.
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Affiliation(s)
- Javier Cotignola
- Laboratorio de Inflamación y Cáncer, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina.,IQUIBICEN, CONICET, Buenos Aires, Argentina
| | - Sandra Rozental
- Centro Nacional de Genética Médica, ANLIS, Buenos Aires, Argentina
| | - Noemí Buzzalino
- Centro Nacional de Genética Médica, ANLIS, Buenos Aires, Argentina
| | - Liliana Dain
- Centro Nacional de Genética Médica, ANLIS, Buenos Aires, Argentina.,Facultad de Ciencias Exactas y Naturales, Universidad of Buenos Aires, Buenos Aires, Argentina
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