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Sheth H, Nair A, Bhavsar R, Kamate M, Gowda VK, Bavdekar A, Kadam S, Nampoothiri S, Panigrahi I, Kaur A, Shah S, Mehta S, Jagadeesan S, Suresh I, Kapoor S, Bajaj S, Devi RR, Prajapati A, Godbole K, Patel H, Luhar Z, Shah RC, Iyer A, Bijarnia S, Puri R, Muranjan M, Shah A, Magar S, Gupta N, Tayade N, Gandhi A, Sowani A, Kale S, Jalan A, Solanki D, Dalal A, Mane S, Prabha CR, Sheth F, Joshi CG, Joshi M, Sheth J. Development, validation and application of single molecule molecular inversion probe based novel integrated genetic screening method for 29 common lysosomal storage disorders in India. Hum Genomics 2024; 18:46. [PMID: 38730490 PMCID: PMC11088154 DOI: 10.1186/s40246-024-00613-9] [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: 03/05/2024] [Accepted: 05/01/2024] [Indexed: 05/13/2024] Open
Abstract
BACKGROUND Current clinical diagnosis pathway for lysosomal storage disorders (LSDs) involves sequential biochemical enzymatic tests followed by DNA sequencing, which is iterative, has low diagnostic yield and is costly due to overlapping clinical presentations. Here, we describe a novel low-cost and high-throughput sequencing assay using single-molecule molecular inversion probes (smMIPs) to screen for causative single nucleotide variants (SNVs) and copy number variants (CNVs) in genes associated with 29 common LSDs in India. RESULTS 903 smMIPs were designed to target exon and exon-intron boundaries of targeted genes (n = 23; 53.7 kb of the human genome) and were equimolarly pooled to create a sequencing library. After extensive validation in a cohort of 50 patients, we screened 300 patients with either biochemical diagnosis (n = 187) or clinical suspicion (n = 113) of LSDs. A diagnostic yield of 83.4% was observed in patients with prior biochemical diagnosis of LSD. Furthermore, diagnostic yield of 73.9% (n = 54/73) was observed in patients with high clinical suspicion of LSD in contrast with 2.4% (n = 1/40) in patients with low clinical suspicion of LSD. In addition to detecting SNVs, the assay could detect single and multi-exon copy number variants with high confidence. Critically, Niemann-Pick disease type C and neuronal ceroid lipofuscinosis-6 diseases for which biochemical testing is unavailable, could be diagnosed using our assay. Lastly, we observed a non-inferior performance of the assay in DNA extracted from dried blood spots in comparison with whole blood. CONCLUSION We developed a flexible and scalable assay to reliably detect genetic causes of 29 common LSDs in India. The assay consolidates the detection of multiple variant types in multiple sample types while having improved diagnostic yield at same or lower cost compared to current clinical paradigm.
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Affiliation(s)
- Harsh Sheth
- FRIGE Institute of Human Genetics, FRIGE House, Jodhpur Village Road, Satellite, Ahmedabad, India, 380015.
| | - Aadhira Nair
- FRIGE Institute of Human Genetics, FRIGE House, Jodhpur Village Road, Satellite, Ahmedabad, India, 380015
| | - Riddhi Bhavsar
- FRIGE Institute of Human Genetics, FRIGE House, Jodhpur Village Road, Satellite, Ahmedabad, India, 380015
| | - Mahesh Kamate
- KLES Prabhakar Kore Hospital, Belgaum, Karnataka, India
| | - Vykuntaraju K Gowda
- Department of Pediatric Neurology, Indira Gandhi Institute of Child Health, Bangalore, India
| | | | - Sandeep Kadam
- Department of Pediatrics, K.E.M Hospital, Pune, India
| | | | - Inusha Panigrahi
- Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Anupriya Kaur
- Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Siddharth Shah
- Royal Institute of Child Neurosciences, Vastrapur, Ahmedabad, India
| | - Sanjeev Mehta
- Royal Institute of Child Neurosciences, Vastrapur, Ahmedabad, India
| | - Sujatha Jagadeesan
- Department of Clinical Genetics and Genetic Counselling, Mediscan Systems, Chennai, India
| | - Indrani Suresh
- Department of Clinical Genetics and Genetic Counselling, Mediscan Systems, Chennai, India
| | - Seema Kapoor
- Division of Genetics and Metabolism Department of Pediatrics, Lok Nayak Hospital and Maulana Azad Medical College, New Delhi, India
| | - Shruti Bajaj
- The Purple Gene Clinic, Simplex Khushaangan, SV Road, Malad West, Mumbai, India
| | | | | | - Koumudi Godbole
- Deenanath Mangeshkar Hospital &Amp; Research Centre, Pune, India
| | - Harsh Patel
- Zydus Hospital & Healthcare Research Pvt Ltd, Ahmedabad, India
| | | | - Raju C Shah
- Ankur Institute of Child Health, Ahmedabad, India
| | | | - Sunita Bijarnia
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | - Ratna Puri
- Institute of Medical Genetics and Genomics, Sir Ganga Ram Hospital, New Delhi, India
| | - Mamta Muranjan
- Department of Paediatrics, KEM Hospital, Parel, Mumbai, India
| | - Ami Shah
- BJ Wadia Hospital for Children, Parel, Mumbai, India
| | | | - Neerja Gupta
- Division of Genetics, Department of Pediatrics, All India Institute of Medical Sciences, New Delhi, India
| | - Naresh Tayade
- Department of Pediatrics, Dr. Panjabrao Deshmukh Memorial Medical College, Amravati, India
| | | | - Ajit Sowani
- Zydus Hospital & Healthcare Research Pvt Ltd, Ahmedabad, India
| | - Shrutikaa Kale
- FRIGE Institute of Human Genetics, FRIGE House, Jodhpur Village Road, Satellite, Ahmedabad, India, 380015
| | | | - Dhaval Solanki
- Mantra Child Neurology and Epilepsy Hospital, Bhavnagar, India
| | - Ashwin Dalal
- Diagnostics Division, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, India
| | - Shrikant Mane
- Department of Genetics, Yale School of Medicine, Yale Center for Genome Analysis, West Haven, CT, USA
| | - C Ratna Prabha
- Department of Biochemistry, Faculty of Science, The M. S. University of Baroda, Vadodara, India
| | - Frenny Sheth
- FRIGE Institute of Human Genetics, FRIGE House, Jodhpur Village Road, Satellite, Ahmedabad, India, 380015
| | | | - Madhvi Joshi
- Gujarat Biotechnology Research Centre, Gandhinagar, Gujarat, India
| | - Jayesh Sheth
- FRIGE Institute of Human Genetics, FRIGE House, Jodhpur Village Road, Satellite, Ahmedabad, India, 380015.
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2
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Fan S, Wu H, Wang R, Chen Q, Zhang X. Congenital disorders of glycosylation with multiorgan disruption and immune dysregulation caused by compound heterozygous variants in MAN2B2. Mol Genet Genomic Med 2024; 12:e2422. [PMID: 38622837 PMCID: PMC11019143 DOI: 10.1002/mgg3.2422] [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: 12/17/2023] [Revised: 02/20/2024] [Accepted: 03/19/2024] [Indexed: 04/17/2024] Open
Abstract
BACKGROUND Congenital disorders of glycosylation (CDG) are a type of inborn error of metabolism (IEM) resulting from defects in glycan synthesis or failed attachment of glycans to proteins or lipids. One rare type of CDG is caused by homozygous or compound heterozygous loss-of-function variants in mannosidase alpha class 2B member 2 (MAN2B2). To date, only two cases of MAN2B2-CDG have been reported worldwide. METHODS Trio whole-exome sequencing (Trio-WES) was conducted to screen for candidate variants. N-glycan profiles were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). MAN2B2 expression was evaluated by western blotting. MX dynamin like GTPase 1 (MX1) function was estimated via Thogoto virus (THOV) minireplicon assay. RESULTS Trio-WES identified compound heterozygous MAN2B2 (hg19, NM_015274.1) variants (c.384G>T; c.926T>A) in a CDG patient. This patient exhibited metabolic abnormalities, symptoms of digestive tract dysfunction, infection, dehydration, and seizures. Novel immune dysregulation characterized by abnormal lymphocytes and immunoglobulin was observed. The MAN2B2 protein level was not affected, while LC-MS/MS showed obvious disruption of N-glycans and N-linked glycoproteins. CONCLUSION We described a CDG patient with novel phenotypes and disruptive N-glycan profiling caused by compound heterozygous MAN2B2 variants (c.384G>T; c.926T>A). Our findings broadened both the genetic and clinical spectra of CDG.
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Affiliation(s)
- Shiqi Fan
- McKusick‐Zhang Center for Genetic Medicine, State Key Laboratory for Complex Severe and Rare Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijingChina
| | - Huanhuan Wu
- Department of NeurologyThe Affiliated Hospital of Capital Institute of PediatricsBeijingChina
| | - Rongrong Wang
- McKusick‐Zhang Center for Genetic Medicine, State Key Laboratory for Complex Severe and Rare Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijingChina
| | - Qian Chen
- Department of NeurologyThe Affiliated Hospital of Capital Institute of PediatricsBeijingChina
| | - Xue Zhang
- McKusick‐Zhang Center for Genetic Medicine, State Key Laboratory for Complex Severe and Rare Diseases, Institute of Basic Medical Sciences Chinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijingChina
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3
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Tian Q, Shu L, Shu C, Xi H, Ma N, Mao X, Wang H. Compound heterozygous variants in MAN2B2 identified in a Chinese child with congenital disorders of glycosylation. Eur J Hum Genet 2023; 31:1455-1457. [PMID: 35637269 PMCID: PMC10689725 DOI: 10.1038/s41431-022-01125-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 03/18/2022] [Accepted: 05/16/2022] [Indexed: 11/09/2022] Open
Abstract
Congenital disorders of glycosylation (CDG) is a group inherited disorders. It is characterized by multi-organ dysfunction with significant morbidity and mortality. MAN2B2-CDG caused by pathogenic variants in the MAN2B2 gene was a rare CDG. To date, only one case of MAN2B2-CDG was reported. The representative clinical features were immune deficiency, dysmorphic facial features, coagulopathy, and severe developmental delay. More cases are needed to support the pathogenesis of MAN2B2 variation and elucidate its clinical heterogeneity. In this study, we described the clinical presentations of a CDG proband with compound heterozygous variants in MAN2B2. Serum N-glycan profiling was measured by MALDI coupled to time-of-flight mass spectrometry (MALDI-TOF MS). MALDI-TOF MS analysis of patient serum showed disorders of N-linked glycosylation, including increased N-glycans and elevated Man5/Man6 and Man5/Man9 value. Our proband presented severe developmental delay, dysmorphic facial features as in the previous case. But our case presented new features, including cleft palate and hypospadias with no immune deficiency. Our data expands both the molecular and clinical phenotypes of MAN2B2-CDG and highlights the importance of the role of MAN2B2 gene in CDG.
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Affiliation(s)
- Qi Tian
- Department of Obstetrics & Gynecology, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan, 410008, China
- National Health Commission Key Laboratory for Birth Defect Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China
| | - Li Shu
- National Health Commission Key Laboratory for Birth Defect Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China
| | - Chuqiang Shu
- Department of Obstetrics & Gynecology, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan, 410008, China
| | - Hui Xi
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan, 410008, China
| | - Na Ma
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan, 410008, China
| | - Xiao Mao
- National Health Commission Key Laboratory for Birth Defect Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China.
| | - Hua Wang
- National Health Commission Key Laboratory for Birth Defect Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China.
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan, 410008, China.
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4
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Roos D, van Leeuwen K, Madkaikar M, Kambli PM, Gupta M, Mathews V, Rawat A, Kuhns DB, Holland SM, de Boer M, Kanegane H, Parvaneh N, Lorenz M, Schwarz K, Klein C, Sherkat R, Jafari M, Wolach B, den Dunnen JT, Kuijpers TW, Köker MY. Hematologically important mutations: Leukocyte adhesion deficiency (second update). Blood Cells Mol Dis 2023; 99:102726. [PMID: 36696755 DOI: 10.1016/j.bcmd.2023.102726] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 01/16/2023] [Accepted: 01/16/2023] [Indexed: 01/22/2023]
Abstract
Leukocyte adhesion deficiency (LAD) is an immunodeficiency caused by defects in the adhesion of leukocytes (especially neutrophils) to the blood vessel wall. As a result, patients with LAD suffer from severe bacterial infections and impaired wound healing, accompanied by neutrophilia. In LAD-I, characterized directly after birth by delayed separation of the umbilical cord, mutations are found in ITGB2, the gene that encodes the β subunit (CD18) of the β2 integrins. In the rare LAD-II disease, the fucosylation of selectin ligands is disturbed, caused by mutations in SLC35C1, the gene that encodes a GDP-fucose transporter of the Golgi system. LAD-II patients lack the H and Lewis Lea and Leb blood group antigens. Finally, in LAD-III, the conformational activation of the hematopoietically expressed β integrins is disturbed, leading to leukocyte and platelet dysfunction. This last syndrome is caused by mutations in FERMT3, encoding the kindlin-3 protein in all blood cells, involved in the regulation of β integrin conformation. This article contains an update of the mutations that we consider to be relevant for the various forms of LAD.
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Affiliation(s)
- Dirk Roos
- Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Center, location AMC, University of Amsterdam, Amsterdam, the Netherlands.
| | - Karin van Leeuwen
- Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Center, location AMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Manisha Madkaikar
- Pediatric Immunology and Leukocyte Biology Lab CMR, National Institute of Immunohaematology, K E M Hospital, Parel, Mumbai, India
| | - Priyanka M Kambli
- Pediatric Immunology and Leukocyte Biology Lab CMR, National Institute of Immunohaematology, K E M Hospital, Parel, Mumbai, India
| | - Maya Gupta
- Pediatric Immunology and Leukocyte Biology Lab CMR, National Institute of Immunohaematology, K E M Hospital, Parel, Mumbai, India
| | - Vikram Mathews
- Dept of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Amit Rawat
- Paediatric Allergy Immunology Unit, Department of Paediatrics, Advanced Paediatrics Centre, Chandigarh, India
| | - Douglas B Kuhns
- Neutrophil Monitoring Laboratory, Applied/Developmental Research Directorate, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Steven M Holland
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA
| | - Martin de Boer
- Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Center, location AMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Hirokazu Kanegane
- Department of Child Health and Development, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Nima Parvaneh
- Infectious Disease Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Myriam Lorenz
- Institute for Transfusion Medicine, University Ulm, Ulm, Germany
| | - Klaus Schwarz
- Institute for Transfusion Medicine, University Ulm, Ulm, Germany; Institute for Clinical Transfusion Medicine and Immunogenetics Ulm, German Red Cross Blood Service Baden-Württemberg - Hessen, Ulm, Germany
| | - Christoph Klein
- Dr. von Hauner Children's Hospital, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Roya Sherkat
- Immunodeficiency Diseases Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mahbube Jafari
- Immunodeficiency Diseases Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Baruch Wolach
- Pediatric Immunology Service, Edmond and Lily Safra Children's Hospital, Chaim Sheba Medical Center, Tel Hashomer, Israel
| | - Johan T den Dunnen
- Human Genetics, Leiden University Medical Center, Leiden, the Netherlands
| | - Taco W Kuijpers
- Sanquin Research, and Landsteiner Laboratory, Amsterdam University Medical Center, location AMC, University of Amsterdam, Amsterdam, the Netherlands; Emma Children's Hospital, Amsterdam University Medical Centre, location AMC, Amsterdam, the Netherlands
| | - M Yavuz Köker
- Department of Immunology, Erciyes Medical School, University of Erciyes, Kayseri, Türkiye
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5
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González-Domínguez CA, Fiesco-Roa MO, Gómez-Carmona S, Kleinert-Altamirano API, He M, Daniel EJP, Raymond KM, Abreu-González M, Manrique-Hernández S, González-Jaimes A, Salinas-Marín R, Molina-Garay C, Carrillo-Sánchez K, Flores-Lagunes LL, Jiménez-Olivares M, Muñoz-Rivas A, Cruz-Muñoz ME, Ruíz-García M, Freeze HH, Mora-Montes HM, Alaez-Verson C, Martínez-Duncker I. ALG1-CDG Caused by Non-functional Alternative Splicing Involving a Novel Pathogenic Complex Allele. Front Genet 2021; 12:744884. [PMID: 34567092 PMCID: PMC8458739 DOI: 10.3389/fgene.2021.744884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 08/05/2021] [Indexed: 11/13/2022] Open
Abstract
This study reports on a Mexican mestizo patient with a multi-systemic syndrome including neurological involvement and a type I serum transferrin profile. Clinical exome sequencing revealed complex alleles in ALG1, the encoding gene for the chitobiosyldiphosphodolichol beta-mannosyltransferase that participates in the formation of the dolichol-pyrophosphate-GlcNAc2Man5, a lipid-linked glycan intermediate during N-glycan synthesis. The identified complex alleles were NM_019109.5(ALG1): c.[208 + 16_208 + 19dup; 208 + 25G > T] and NM_019109.5(ALG1): c.[208 + 16_208 + 19dup; 1312C > T]. Although both alleles carried the benign variant c.208 + 16_208 + 19dup, one allele carried a known ALG1 pathogenic variant (c.1312C > T), while the other carried a new uncharacterized variant (c.208 + 25G > T) causing non-functional alternative splicing that, in conjunction with the benign variant, defines the pathogenic protein effect (p.N70S_S71ins9). The presence in the patient’s serum of the pathognomonic N-linked mannose-deprived tetrasaccharide marker for ALG1-CDG (Neu5Acα2,6Galβ1,4-GlcNAcβ1,4GlcNAc) further supported this diagnosis. This is the first report of an ALG1-CDG patient from Latin America.
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Affiliation(s)
- Carlos Alberto González-Domínguez
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico.,Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Moisés O Fiesco-Roa
- Programa de Maestría y Doctorado en Ciencias Médicas, Universidad Nacional Autónoma de México (UNAM), Ciudad Universitaria, Mexico City, Mexico.,Laboratorio de Citogenética, Instituto Nacional de Pediatría, Mexico City, Mexico
| | | | - Anke Paula Ingrid Kleinert-Altamirano
- Centro de Rehabilitación e Inclusión Infantil Teletón, Tuxtla Gutiérrez, Mexico.,Palmieri Metabolic Disease Laboratory, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Miao He
- Hospital Regional de Alta Especialidad Ciudad Salud, Tapachula, Mexico
| | | | - Kimiyo M Raymond
- Department of Laboratory Medicine and Pathology, Laboratory Genetics and Genomics, Mayo Clinic, Rochester, MN, United States
| | | | - Sandra Manrique-Hernández
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico.,Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Ana González-Jaimes
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
| | - Roberta Salinas-Marín
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
| | - Carolina Molina-Garay
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Mexico City, Mexico
| | - Karol Carrillo-Sánchez
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Mexico City, Mexico
| | - Luis Leonardo Flores-Lagunes
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Mexico City, Mexico
| | - Marco Jiménez-Olivares
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Mexico City, Mexico
| | - Anallely Muñoz-Rivas
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Mexico City, Mexico
| | - Mario E Cruz-Muñoz
- Laboratorio de Inmunología Molecular, Facultad de Medicina, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
| | - Matilde Ruíz-García
- Departamento de Neurología, Instituto Nacional de Pediatría, Mexico City, Mexico
| | - Hudson H Freeze
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, United States
| | - Héctor M Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - Carmen Alaez-Verson
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Mexico City, Mexico
| | - Iván Martínez-Duncker
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico.,Sociedad Latinoamericana de Glicobiología A.C., Cuernavaca, Mexico
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6
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González-Domínguez C, Villarroel C, Rodríguez-Morales M, Manrique-Hernández S, González-Jaimes A, Olvera-Rodriguez F, Beutelspacher K, Molina-Garay C, Carrillo-Sánchez K, Flores-Lagunes L, Jiménez-Olivares M, Muñoz-Rivas A, Cruz-Muñoz M, Mora-Montes H, Salinas-Marín R, Alaez-Verson C, Martínez-Duncker I. Non-functional alternative splicing caused by a Latino pathogenic variant in a case of PMM2-CDG. Mol Genet Metab Rep 2021; 28:100781. [PMID: 34277356 PMCID: PMC8264207 DOI: 10.1016/j.ymgmr.2021.100781] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/26/2021] [Accepted: 06/27/2021] [Indexed: 12/13/2022] Open
Abstract
We report on a Mexican mestizo with a multisystemic syndrome including neurological involvement and a type I serum transferrin isoelectric focusing (Tf IEF) pattern. Diagnosis of PMM2-CDG was obtained by clinical exome sequencing (CES) that revealed compound heterozygous variants in PMM2, the encoding gene for the phosphomannomutase 2 (PMM2). This enzyme catalyzes the conversion of mannose-6-P to mannose-1-P required for the synthesis of GDP-Man and Dol-P-Man, donor substrates for glycosylation reactions. The identified variants were c.422G>A (R141H) and c.178G>T, the former being the most frequent PMM2 pathogenic mutation and the latter a previously uncharacterized variant restricted to the Latino population with conflicting interpretations of pathogenicity and that we here report causes leaky non-functional alternative splicing (p.V60Cfs*3).
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Affiliation(s)
- C.A. González-Domínguez
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Mexico
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca 62210, Mexico
| | - C.E. Villarroel
- Departamento de Genética, Instituto Nacional de Pediatría, Ciudad de México 04530, Mexico
| | - M. Rodríguez-Morales
- Departamento de Genética, Instituto Nacional de Pediatría, Ciudad de México 04530, Mexico
| | - S. Manrique-Hernández
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Mexico
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca 62210, Mexico
| | - A. González-Jaimes
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Mexico
| | - F. Olvera-Rodriguez
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca 62210, Mexico
| | - K. Beutelspacher
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Mexico
| | - C. Molina-Garay
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Ciudad de México 14610, Mexico
| | - K. Carrillo-Sánchez
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Ciudad de México 14610, Mexico
| | - L.L. Flores-Lagunes
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Ciudad de México 14610, Mexico
| | - M. Jiménez-Olivares
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Ciudad de México 14610, Mexico
| | - A. Muñoz-Rivas
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Ciudad de México 14610, Mexico
| | - M.E. Cruz-Muñoz
- Laboratorio de Inmunología Molecular, Facultad de Medicina, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Mexico
| | - H.M. Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato 36050, Mexico
| | - R. Salinas-Marín
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Mexico
| | - C. Alaez-Verson
- Laboratorio de Diagnóstico Genómico, Instituto Nacional de Medicina Genómica, Secretaría de Salud, Ciudad de México 14610, Mexico
| | - I. Martínez-Duncker
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, Mexico
- Corresponding author.
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7
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Zhong Y, Xu F, Wu J, Schubert J, Li MM. Application of Next Generation Sequencing in Laboratory Medicine. Ann Lab Med 2021; 41:25-43. [PMID: 32829577 PMCID: PMC7443516 DOI: 10.3343/alm.2021.41.1.25] [Citation(s) in RCA: 85] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/24/2020] [Accepted: 08/07/2020] [Indexed: 12/12/2022] Open
Abstract
The rapid development of next-generation sequencing (NGS) technology, including advances in sequencing chemistry, sequencing technologies, bioinformatics, and data interpretation, has facilitated its wide clinical application in precision medicine. This review describes current sequencing technologies, including short- and long-read sequencing technologies, and highlights the clinical application of NGS in inherited diseases, oncology, and infectious diseases. We review NGS approaches and clinical diagnosis for constitutional disorders; summarize the application of U.S. Food and Drug Administration-approved NGS panels, cancer biomarkers, minimal residual disease, and liquid biopsy in clinical oncology; and consider epidemiological surveillance, identification of pathogens, and the importance of host microbiome in infectious diseases. Finally, we discuss the challenges and future perspectives of clinical NGS tests.
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Affiliation(s)
- Yiming Zhong
- Department of Pathology & Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA,
USA
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA,
USA
| | - Feng Xu
- Department of Pathology & Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA,
USA
| | - Jinhua Wu
- Department of Pathology & Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA,
USA
| | - Jeffrey Schubert
- Department of Pathology & Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA,
USA
| | - Marilyn M. Li
- Department of Pathology & Laboratory Medicine, Children’s Hospital of Philadelphia, Philadelphia, PA,
USA
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA,
USA
- Department of Pediatrics, Children’s Hospital of Philadelphia, Philadelphia, PA,
USA
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8
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Salinas V, Vega P, Marsili L, Pérez‐Maturo J, Martínez N, Zavala L, González‐Morón D, Medina N, Rodriguez‐Quiroga SA, Amartino H, Maxit C, Sturchio A, Grimberg B, Duque K, Comas B, Silva W, Consalvo D, Sfaello I, Espay AJ, Kauffman MA. The odyssey of complex neurogenetic disorders: From undetermined to positive. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2020; 184:876-884. [DOI: 10.1002/ajmg.c.31848] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/14/2020] [Accepted: 09/27/2020] [Indexed: 12/22/2022]
Affiliation(s)
- Valeria Salinas
- Neurogenetics Unit, Hospital JM Ramos Mejía Buenos Aires Argentina
- Faculty of Biomedical Sciences, Precision Medicine and Clinical Genomics Group, Translational Medicine Research Institute‐CONICET Universidad Austral Buenos Aires Argentina
| | - Patricia Vega
- Neurogenetics Unit, Hospital JM Ramos Mejía Buenos Aires Argentina
| | - Luca Marsili
- UC Gardner Neuroscience Institute, Department of Neurology, Gardner Center for Parkinson's disease and Movement Disorders University of Cincinnati Ohio
| | - Josefina Pérez‐Maturo
- Neurogenetics Unit, Hospital JM Ramos Mejía Buenos Aires Argentina
- Faculty of Biomedical Sciences, Precision Medicine and Clinical Genomics Group, Translational Medicine Research Institute‐CONICET Universidad Austral Buenos Aires Argentina
| | - Nerina Martínez
- Neurogenetics Unit, Hospital JM Ramos Mejía Buenos Aires Argentina
| | - Lucia Zavala
- Neurogenetics Unit, Hospital JM Ramos Mejía Buenos Aires Argentina
| | | | - Nancy Medina
- Neurogenetics Unit, Hospital JM Ramos Mejía Buenos Aires Argentina
| | | | - Hernán Amartino
- Pediatric Neurology Unit Hospital Universitario Austral Buenos Aires Argentina
| | - Clarisa Maxit
- Pediatric Neurology Unit, Hospital Italiano de Buenos Aires Buenos Aires Argentina
| | - Andrea Sturchio
- UC Gardner Neuroscience Institute, Department of Neurology, Gardner Center for Parkinson's disease and Movement Disorders University of Cincinnati Ohio
| | - Barbara Grimberg
- UC Gardner Neuroscience Institute, Department of Neurology, Gardner Center for Parkinson's disease and Movement Disorders University of Cincinnati Ohio
| | - Kevin Duque
- UC Gardner Neuroscience Institute, Department of Neurology, Gardner Center for Parkinson's disease and Movement Disorders University of Cincinnati Ohio
| | - Betiana Comas
- Neurology Unit, Hospital de la Baxada “Dra. Teresa Ratto” Paraná Entre Ríos Argentina
| | - Walter Silva
- Pediatric Neurology Unit, Hospital Italiano de Buenos Aires Buenos Aires Argentina
| | - Damián Consalvo
- Neurology Unit, Hospital JM Ramos Mejía Buenos Aires Argentina
| | - Ignacio Sfaello
- CETES, Instituto de Neurología Infanto‐Juvenil Córdoba Argentina
| | - Alberto J. Espay
- UC Gardner Neuroscience Institute, Department of Neurology, Gardner Center for Parkinson's disease and Movement Disorders University of Cincinnati Ohio
| | - Marcelo A. Kauffman
- Neurogenetics Unit, Hospital JM Ramos Mejía Buenos Aires Argentina
- Faculty of Biomedical Sciences, Precision Medicine and Clinical Genomics Group, Translational Medicine Research Institute‐CONICET Universidad Austral Buenos Aires Argentina
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9
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Sabo A, Murdock D, Dugan S, Meng Q, Gingras MC, Hu J, Muzny D, Gibbs R. Community-based recruitment and exome sequencing indicates high diagnostic yield in adults with intellectual disability. Mol Genet Genomic Med 2020; 8:e1439. [PMID: 32767738 PMCID: PMC7549560 DOI: 10.1002/mgg3.1439] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/12/2020] [Accepted: 07/01/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Establishing a genetic diagnosis for individuals with intellectual disability (ID) benefits patients and their families as it may inform the prognosis, lead to appropriate therapy, and facilitate access to medical and supportive services. Exome sequencing has been successfully applied in a diagnostic setting, but most clinical exome referrals are pediatric patients, with many adults with ID lacking a comprehensive genetic evaluation. METHODS Our unique recruitment strategy involved partnering with service and education providers for individuals with ID. We performed exome sequencing and analysis, and clinical variant interpretation for each recruited family. RESULTS All five families enrolled in the study opted-in for the return of genetic results. In three out of five families exome sequencing analysis identified pathogenic or likely pathogenic variants in KANSL1, TUSC3, and MED13L genes. Families discussed the results and any potential medical follow-up in an appointment with a board certified clinical geneticist. CONCLUSION Our study suggests high yield of exome sequencing as a diagnostic tool in adult patients with ID who have not undergone comprehensive sequencing-based genetic testing. Research studies including an option of return of results through a genetic clinic could help minimize the disparity in exome diagnostic testing between pediatric and adult patients with ID.
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Affiliation(s)
- Aniko Sabo
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
| | - David Murdock
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
| | - Shannon Dugan
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
| | - Qingchang Meng
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
| | | | - Jianhong Hu
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
| | - Donna Muzny
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
| | - Richard Gibbs
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX, USA
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10
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Knapp KM, Luu R, Baerenfaenger M, Zijlstra F, Wessels HJCT, Jenkins D, Lefeber DJ, Neas K, Bicknell LS. Biallelic variants in SLC35C1 as a cause of isolated short stature with intellectual disability. J Hum Genet 2020; 65:743-750. [PMID: 32313197 DOI: 10.1038/s10038-020-0764-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 04/07/2020] [Accepted: 04/09/2020] [Indexed: 11/09/2022]
Abstract
Variants in SLC35C1 underlie leucocyte adhesion deficiency (LADII) or congenital disorder of glycosylation type 2c (CDGIIc), an autosomal recessive disorder of fucosylation. This immunodeficiency syndrome is generally characterized by severe recurrent infections, Bombay blood group, reduced growth and intellectual disability (ID). Features are all caused by an inability to generate key fucosylated molecules due to a defective transport of GDP-fucose into the Golgi. Here we report the use of exome sequencing to identify biallelic variants in SLC35C1 (c.501_503delCTT, p.(Phe168del) and c.891T > G, p.(Asn297Lys)) in an individual with short stature and ID. Retrospective clinical examination based on the genetic findings revealed increased otitis media as the only immunological feature present in this child. Biochemical analysis of patient serum identified a clear but mild decrease in protein fucosylation. Modelling all described missense mutations on a SLC35C1 protein model showed pathogenic substitutions localise to close to the dimer interface, providing insight into the possible pathophysiology of non-synonymous causative variants identified in patients. Our evidence confirms this is the second family presenting with only a subset of features and broadens the clinical presentation of this syndrome. Of note, both families segregated a common allele (p.Phe168del), suggesting there could be an associated genotype-phenotype relationship for specific variants. Based on two out of 14 reported families not presenting with the characteristic features of SLC35C1-CDG, we suggest there is clinical utility in considering this gene in patients with short stature and ID.
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Affiliation(s)
- Karen M Knapp
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Rebecca Luu
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Melissa Baerenfaenger
- Department of Neurology, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Center, Nijmegen, Netherlands
| | - Fokje Zijlstra
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Hans J C T Wessels
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Danielle Jenkins
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Dirk J Lefeber
- Department of Neurology, Donders Institute for Brain, Cognition, and Behavior, Radboud University Medical Center, Nijmegen, Netherlands.,Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Katherine Neas
- Genetic Health Services New Zealand, Wellington, New Zealand
| | - Louise S Bicknell
- Department of Pathology, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.
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11
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Bevilacqua JA, Guecaimburu Ehuletche MDR, Perna A, Dubrovsky A, Franca MC, Vargas S, Hegde M, Claeys KG, Straub V, Daba N, Faria R, Periquet M, Sparks S, Thibault N, Araujo R. The Latin American experience with a next generation sequencing genetic panel for recessive limb-girdle muscular weakness and Pompe disease. Orphanet J Rare Dis 2020; 15:11. [PMID: 31931849 PMCID: PMC6958675 DOI: 10.1186/s13023-019-1291-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 12/27/2019] [Indexed: 02/08/2023] Open
Abstract
Background Limb-girdle muscular dystrophy (LGMD) is a group of neuromuscular disorders of heterogeneous genetic etiology with more than 30 directly related genes. LGMD is characterized by progressive muscle weakness involving the shoulder and pelvic girdles. An important differential diagnosis among patients presenting with proximal muscle weakness (PMW) is late-onset Pompe disease (LOPD), a rare neuromuscular glycogen storage disorder, which often presents with early respiratory insufficiency in addition to PMW. Patients with PMW, with or without respiratory symptoms, were included in this study of Latin American patients to evaluate the profile of variants for the included genes related to LGMD recessive (R) and LOPD and the frequency of variants in each gene among this patient population. Results Over 20 institutions across Latin America (Brazil, Argentina, Peru, Ecuador, Mexico, and Chile) enrolled 2103 individuals during 2016 and 2017. Nine autosomal recessive LGMDs and Pompe disease were investigated in a 10-gene panel (ANO5, CAPN3, DYSF, FKRP, GAA, SGCA, SGCB, SGCD, SGCG, TCAP) based on reported disease frequency in Latin America. Sequencing was performed with Illumina’s NextSeq500 and variants were classified according to ACMG guidelines; pathogenic and likely pathogenic were treated as one category (P) and variants of unknown significance (VUS) are described. Genetic variants were identified in 55.8% of patients, with 16% receiving a definitive molecular diagnosis; 39.8% had VUS. Nine patients were identified with Pompe disease. Conclusions The results demonstrate the effectiveness of this targeted genetic panel and the importance of including Pompe disease in the differential diagnosis for patients presenting with PMW.
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Affiliation(s)
- Jorge A Bevilacqua
- Departamento de Neurología y Neurocirugía, Hospital Clínico, Universidad de Chile, Santiago, Chile.,Departamento de Anatomía y Medicina Legal, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Departamento de Neurología y Neurocirugía, Clínica Dávila, Santiago, Chile
| | | | - Abayuba Perna
- Institute of Neurology, Hospital de Clínicas, School of Medicine, UDELAR, Montevideo, Uruguay
| | - Alberto Dubrovsky
- Institute of Neuroscience, Favaloro Foundation, Buenos Aires, Argentina
| | - Marcondes C Franca
- Department of Neurology, University of Campinas-UNICAMP, Campinas, Sao Paulo, Brazil
| | - Steven Vargas
- Center of Neurology and Neurosurgery, Mexico City, Mexico
| | - Madhuri Hegde
- Global Laboratory Services, Diagnostics, PerkinElmer, Waltham, MA, USA
| | - Kristl G Claeys
- Department of Neurology, University Hospitals Leuven, Leuven, Belgium.,Laboratory for Muscle Diseases and Neuropathies, Department of Neurosciences, KU Leuven, Campus Gasthuisberg, Leuven, Belgium
| | - Volker Straub
- John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University, Centre for Life, Newcastle, United Kingdom
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12
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Identification and characterization of novel mutations in MOGS in a Chinese patient with infantile spams. Neurogenetics 2020; 21:97-104. [DOI: 10.1007/s10048-019-00590-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 09/05/2019] [Indexed: 02/07/2023]
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13
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Pshenichnikova OS, Goncharova MV, Pustovoit YS, Karpova IV, Surin VL. PILOT RESEARCH OF A GENETIC PREDISPOSITION FOR CLINICAL MANIFESTATIONS OF ACUTE INTERMITTENT PORPHYRIA. RUSSIAN JOURNAL OF HEMATOLOGY AND TRANSFUSIOLOGY 2019. [DOI: 10.35754/0234-5730-2019-64-2-123-137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Introduction.Acute intermittent porphyria (AIP) is the most common and severe form of acute hepatic porphyria. AIP is caused by a deficiency in the third enzyme of the heme biosynthesis system — hydroxymethylbilanine synthase (HMBS) — and has a dominant inheritance type. However, the probability of the clinical manifestation of this condition in carriers of the mutation in the HMBS gene constitutes only 10–20 %. Thi s suggests that the presence of such a mutation can be a necessary but not a sufficient condition for the development of the disease.Aim.To search for additional genetic factors, which determine the clinical penetrance of AIP using Whole-Exome Sequencing.Materials and methods.Sequencing of the whole exome was performed using a TruSeqExomeLibraryPrepkit (Illumina) kit by an Illumina HiSeq4000 instrument for 6 women with API with known mutations in the HMBS gene. All the patients suffered from a severe form of the disease. As a reference, a version of the hg19 human genome was used.Results.No common mutations were found in the examined patients. However, in each patient, functional variations were found in the genes related to detoxification systems, regulation of the heme biosynthesis cascade and expression of delta-aminolevulinic acid synthase (ALAS1) and in genes of proteins regulating nervous system. These variations require further study involving an extended number of patients with AIP manifestations and their relatives, who are asymptomatic carriers of disorders in the gene HMBS.Conclusions.The results obtained have allowed us to formulate a hypothesis about a possible role of genetic defects in the penetrance of AIP, which determine the development of other neurological pathologies. This is evidenced by the presence of gene pathogenic variations in 5 out of 6 examined patients, defects in which are associated with hereditary myasthenia and muscle atrophy.
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14
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Gheldof A, Seneca S, Stouffs K, Lissens W, Jansen A, Laeremans H, Verloo P, Schoonjans AS, Meuwissen M, Barca D, Martens G, De Meirleir L. Clinical implementation of gene panel testing for lysosomal storage diseases. Mol Genet Genomic Med 2018; 7:e00527. [PMID: 30548430 PMCID: PMC6393649 DOI: 10.1002/mgg3.527] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 10/26/2018] [Accepted: 11/07/2018] [Indexed: 02/06/2023] Open
Abstract
Background The diagnostic workup in patients with a clinical suspicion of lysosomal storage diseases (LSD) is often difficult due to the variability in the clinical phenotype. The gold standard for diagnosis of LSDs consists of enzymatic testing. However, due to the sequential nature of this methodology and inconsistent genotype–phenotype correlations of certain LSDs, finding a diagnosis can be challenging. Method We developed and clinically implemented a gene panel covering 50 genes known to cause LSDs when mutated. Over a period of 18 months, we analyzed 150 patients who were referred for LSD testing and compared these results with the data of patients who were previously enrolled in a scheme of classical biochemical testing. Results Our panel was able to determine the molecular cause of the disease in 22 cases (15%), representing an increase in diagnostic yield compared to biochemical tests developed for 21 LSDs (4.6%). We were furthermore able to redirect the diagnosis of a mucolipidosis patient who was initially suspected to be affected with galactosialidosis. Several patients were identified as being affected with neuronal ceroid lipofuscinosis, which cannot readily be detected by enzyme testing. Finally, several carriers of pathogenic mutations in LSD genes related to the disease phenotype were identified as well, thus potentially increasing the diagnostic yield of the panel as heterozygous deletions cannot be detected. Conclusion We show that the implementation of a gene panel for LSD diagnostics results in an increased yield in comparison to classical biochemical testing. As the panel is able to cover a wider range of diseases, we propose to implement this methodology as a first‐tier test in cases of an aspecific LSD presentation, while enzymatic testing remains the first choice in patients with a more distinctive clinical presentation. Positive panel results should however still be enzymatically confirmed whenever possible.
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Affiliation(s)
- Alexander Gheldof
- Center for Medical Genetics, UZ Brussel, Brussels, Belgium.,Neurogenetics Research Group, Reproduction Genetics and Regenerative Medicine Research Group, Vrije Universiteit Brussel, Brussels, Belgium
| | - Sara Seneca
- Center for Medical Genetics, UZ Brussel, Brussels, Belgium.,Neurogenetics Research Group, Reproduction Genetics and Regenerative Medicine Research Group, Vrije Universiteit Brussel, Brussels, Belgium
| | - Katrien Stouffs
- Center for Medical Genetics, UZ Brussel, Brussels, Belgium.,Neurogenetics Research Group, Reproduction Genetics and Regenerative Medicine Research Group, Vrije Universiteit Brussel, Brussels, Belgium
| | - Willy Lissens
- Center for Medical Genetics, UZ Brussel, Brussels, Belgium.,Neurogenetics Research Group, Reproduction Genetics and Regenerative Medicine Research Group, Vrije Universiteit Brussel, Brussels, Belgium
| | - Anna Jansen
- Paediatric Neurology Unit, Department of Paediatrics, UZ Brussel, Brussels, Belgium
| | | | - Patrick Verloo
- Department of Pediatrics, Ghent University and Ghent University Hospital, Ghent, Belgium
| | - An-Sofie Schoonjans
- Department of Pediatric Neurology, University Hospital Antwerp (UZA), Antwerp, Belgium
| | - Marije Meuwissen
- Department of Medical Genetics, University Hospital Antwerp (UZA), Antwerp, Belgium
| | - Diana Barca
- Clinic of Pediatric Neurology, "Prof. Dr. Alexandru Obregia" Clinical Psychiatric Hospital, Bucharest, Romania.,"Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania
| | - Geert Martens
- VUB Metabolomics Platform, Vrije Universiteit Brussel and Laboratory for Molecular Diagnostics, AZ Delta Roeselare, Roeselare, Belgium
| | - Linda De Meirleir
- Paediatric Neurology Unit, Department of Paediatrics, UZ Brussel, Brussels, Belgium
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15
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Tumienė B, Peterlin B, Maver A, Utkus A. Contemporary scope of inborn errors of metabolism involving epilepsy or seizures. Metab Brain Dis 2018; 33:1781-1786. [PMID: 30006695 DOI: 10.1007/s11011-018-0288-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Accepted: 07/10/2018] [Indexed: 01/15/2023]
Abstract
Many inborn errors of metabolism may present with epilepsy or seizures, however, current scope of these diseases is unknown. Due to available precision medicine approaches in many inborn errors of metabolism and sophisticated traditional diagnostics, this group of disorders is of special relevance to clinicians. Besides, as current treatment is challenging and unsuccessful in more than 30% of all epilepsy patients, these diseases may provide valuable models for ictogenesis and epileptogenesis studies and potentially pave the ways to identification of novel treatments. The aim of this study was to elucidate genetic architecture of inborn errors of metabolism involving epilepsy or seizures and to evaluate their diagnostic approaches. After extensive search, 880 human genes were identified with a considerable part, 373 genes (42%), associated with inborn errors of metabolism. The most numerous group comprised disorders of energy metabolism (115, 31% of all inborn errors of metabolism). A substantial number of these diseases (26%, 97/373) have established specific treatments, therefore timely diagnosis comes as an obligation. Highly heterogenous, overlapping and non-specific phenotypes in most of inborn errors of metabolism presenting with epilepsy or seizures usually preclude phenotype-driven diagnostics. Besides, as traditional diagnostics involves a range of specialized metabolic tests with low diagnostic yields and is generally inefficient and lengthy, next-generation sequencing-based methods were proposed as a cost-efficient one-step way to shorten "diagnostic odyssey". Extensive list of 373 epilepsy- or seizures-associated inborn errors of metabolism genes may be of value in development of gene panels and as a tool for variants' filtration.
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Affiliation(s)
- Birutė Tumienė
- Institute of Biomedical Sciences, Faculty of Medicine, Vilnius University, Santariskiu 2, LT-08661, Vilnius, Lithuania.
- Vilnius University Hospital Santaros Klinikos, Santariskiu 2, LT-08661, Vilnius, Lithuania.
| | - Borut Peterlin
- Clinical Institute for Medical Genetics, Division of Gynecology, University of Ljubljana Medical Centre, Ljubljana, Slovenia
| | - Aleš Maver
- Clinical Institute for Medical Genetics, Division of Gynecology, University of Ljubljana Medical Centre, Ljubljana, Slovenia
| | - Algirdas Utkus
- Institute of Biomedical Sciences, Faculty of Medicine, Vilnius University, Santariskiu 2, LT-08661, Vilnius, Lithuania
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16
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Nicastro E, D'Antiga L. Next generation sequencing in pediatric hepatology and liver transplantation. Liver Transpl 2018; 24:282-293. [PMID: 29080241 DOI: 10.1002/lt.24964] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/04/2017] [Accepted: 10/18/2017] [Indexed: 02/07/2023]
Abstract
Next generation sequencing (NGS) has revolutionized the analysis of human genetic variations, offering a highly cost-effective way to diagnose monogenic diseases (MDs). Because nearly half of the children with chronic liver disorders have a genetic cause and approximately 20% of pediatric liver transplantations are performed in children with MDs, NGS offers the opportunity to significantly improve the diagnostic yield in this field. Among the NGS strategies, the use of targeted gene panels has proven useful to rapidly and reliably confirm a clinical suspicion, whereas the whole exome sequencing (WES) with variants filtering has been adopted to assist the diagnostic workup in unclear clinical scenarios. WES is powerful but challenging because it detects a great number of variants of unknown significance that can be misinterpreted and lead to an incorrect diagnosis. In pediatric hepatology, targeted NGS can be very valuable to discriminate neonatal/infantile cholestatic disorders, disclose genetic causes of acute liver failure, and diagnose the subtype of inborn errors of metabolism presenting with a similar phenotype (such as glycogen storage disorders, mitochondrial cytopathies, or nonalcoholic fatty liver disease). The inclusion of NGS in diagnostic processes will lead to a paradigm shift in medicine, changing our approach to the patient as well as our understanding of factors affecting genotype-phenotype match. In this review, we discuss the opportunities and the challenges offered nowadays by NGS, and we propose a novel algorithm for cholestasis of infancy adopted in our center, including targeted NGS as a pivotal tool for the diagnosis of liver-based MDs. Liver Transplantation 24 282-293 2018 AASLD.
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Affiliation(s)
- Emanuele Nicastro
- Pediatric Hepatology, Gastroenterology and Transplantation, Hospital Papa Giovanni XXIII, Bergamo, Italy
| | - Lorenzo D'Antiga
- Pediatric Hepatology, Gastroenterology and Transplantation, Hospital Papa Giovanni XXIII, Bergamo, Italy
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17
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van den Veyver IB, Eng CM. Genome-Wide Sequencing for Prenatal Detection of Fetal Single-Gene Disorders. Cold Spring Harb Perspect Med 2015; 5:cshperspect.a023077. [PMID: 26253094 DOI: 10.1101/cshperspect.a023077] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
New sequencing methods capable of rapidly analyzing the genome at increasing resolution have transformed diagnosis of single-gene or oligogenic genetic disorders in pediatric and adult medicine. Targeted tests, consisting of disease-focused multigene panels and diagnostic exome sequencing to interrogate the sequence of the coding regions of nearly all genes, are now clinically offered when there is suspicion for an undiagnosed genetic disorder or cancer in children and adults. Implementation of diagnostic exome and genome sequencing tests on invasively and noninvasively obtained fetal DNA samples for prenatal genetic diagnosis is also being explored. We predict that they will become more widely integrated into prenatal care in the near future. Providers must prepare for the practical, ethical, and societal dilemmas that accompany the capacity to generate and analyze large amounts of genetic information about the fetus during pregnancy.
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Affiliation(s)
- Ignatia B van den Veyver
- Department of Obstetrics and Gynecology, Baylor College of Medicine, The Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, Texas 77030 Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
| | - Christine M Eng
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
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18
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Ganetzky R, Izumi K, Edmondson A, Muraresku CC, Zackai E, Deardorff M, Ganesh J. Fetal akinesia deformation sequence due to a congenital disorder of glycosylation. Am J Med Genet A 2015; 167A:2411-7. [DOI: 10.1002/ajmg.a.37184] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 05/15/2015] [Indexed: 12/12/2022]
Affiliation(s)
- Rebecca Ganetzky
- Division of Genetics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania
- Section of Biochemical Genetics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania
| | - Kosuke Izumi
- Division of Genetics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania
- Section of Biochemical Genetics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania
| | - Andrew Edmondson
- The Perelman School of Medicine at The University of Pennsylvania; Philadelphia Pennsylvania
| | - Colleen Clarke Muraresku
- Section of Biochemical Genetics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania
| | - Elaine Zackai
- Division of Genetics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania
- The Perelman School of Medicine at The University of Pennsylvania; Philadelphia Pennsylvania
| | - Matthew Deardorff
- Division of Genetics; The Children's Hospital of Philadelphia; Philadelphia Pennsylvania
- The Perelman School of Medicine at The University of Pennsylvania; Philadelphia Pennsylvania
| | - Jaya Ganesh
- Genetics Program, Children's Regional Hospital; Cooper University Health Care
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19
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Aziz N, Zhao Q, Bry L, Driscoll DK, Funke B, Gibson JS, Grody WW, Hegde MR, Hoeltge GA, Leonard DGB, Merker JD, Nagarajan R, Palicki LA, Robetorye RS, Schrijver I, Weck KE, Voelkerding KV. College of American Pathologists' Laboratory Standards for Next-Generation Sequencing Clinical Tests. Arch Pathol Lab Med 2015; 139:481-93. [DOI: 10.5858/arpa.2014-0250-cp] [Citation(s) in RCA: 265] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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20
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Application of whole exome sequencing to a rare inherited metabolic disease with neurological and gastrointestinal manifestations: a congenital disorder of glycosylation mimicking glycogen storage disease. Clin Chim Acta 2015; 444:50-3. [PMID: 25681648 DOI: 10.1016/j.cca.2015.02.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 02/03/2015] [Indexed: 01/31/2023]
Abstract
BACKGROUND Rare inherited metabolic diseases with neurological and gastrointestinal manifestations can be misdiagnosed as other diseases or remain as disorders with indeterminate etiologies. This study aims to provide evidence to recommend the utility of whole exome sequencing in clinical diagnosis of a rare inherited metabolic disease. METHODS AND RESULTS A 4-month-old female baby visited an outpatient clinic due to poor weight gain, repeated seizure-like episodes, developmental delay, and unexplained hepatomegaly with abnormal liver function test results. Although liver biopsy revealed moderate fibrosis with a suggested diagnosis of glycogen storage disease (GSD), no mutations were identified either by single gene approach for GSD (G6PC and GAA) or by next generation sequencing panels for GSD (including 21 genes). Whole exome sequencing of the patient revealed compound heterozygous mutations of PMM2: c.580C>T (p.Arg194*) and c.713G>C (p.Arg238Pro) which mutations were associated with congenital disorder of glycosylation Ia (CDG-Ia: PMM2-CDG). CONCLUSIONS We successfully applied exome sequencing to diagnose the first reported Korean patient with CDG-Ia, which was misdiagnosed as GSD. Whole exome sequencing may prove to be the preferred strategy for analysis of clinical features that do not readily suggest a specific diagnosis, such as those observed in inherited metabolic diseases, including CDG.
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21
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Ankala A, da Silva C, Gualandi F, Ferlini A, Bean LJH, Collins C, Tanner AK, Hegde MR. A comprehensive genomic approach for neuromuscular diseases gives a high diagnostic yield. Ann Neurol 2014; 77:206-14. [PMID: 25380242 DOI: 10.1002/ana.24303] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 10/31/2014] [Accepted: 11/02/2014] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Neuromuscular diseases (NMDs) are a group of >200 highly genetically as well as clinically heterogeneous inherited genetic disorders that affect the peripheral nervous and muscular systems, resulting in gross motor disability. The clinical and genetic heterogeneities of NMDs make disease diagnosis complicated and expensive, often involving multiple tests. METHODS To expedite the molecular diagnosis of NMDs, we designed and validated several next generation sequencing (NGS)-based comprehensive gene panel tests that include complementary deletion and duplication testing through comparative genomic hybridization arrays. Our validation established the targeted gene panel test to have 100% sensitivity and specificity for single nucleotide variant detection. To compare the clinical diagnostic yields of single gene (NMD-associated) tests with the various NMD NGS panel tests, we analyzed data from all clinical tests performed at the Emory Genetics Laboratory from October 2009 through May 2014. We further compared the clinical utility of the targeted NGS panel test with that of exome sequencing (ES). RESULTS We found that NMD comprehensive panel testing has a 3-fold greater diagnostic yield (46%) than single gene testing (15-19%). Sanger fill-in of low-coverage exons, copy number variation analysis, and thorough in-house validation of the assay all complement panel testing and allow the detection of all types of causative pathogenic variants, some of which (about 18%) may be missed by ES. INTERPRETATION Our results strongly indicate that for molecular diagnosis of heterogeneous disorders such as NMDs, targeted panel testing has the highest clinical yield and should therefore be the preferred first-tier approach.
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Affiliation(s)
- Arunkanth Ankala
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA
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22
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Newman WG, Black GC. Delivery of a clinical genomics service. Genes (Basel) 2014; 5:1001-17. [PMID: 25383561 PMCID: PMC4276923 DOI: 10.3390/genes5041001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Revised: 10/28/2014] [Accepted: 10/30/2014] [Indexed: 01/30/2023] Open
Abstract
Over the past five years, next generation sequencing has revolutionised the discovery of genes responsible for rare inherited diseases previously resistant to traditional discovery techniques. This review considers how this new technology is being introduced into clinical practice to aid diagnosis and improve the clinical management of individuals and families affected by rare diseases where access to genetic testing was previously limited. We compare and contrast the different approaches that have been adopted including panel based tests, exome and genome sequencing. We provide insights from our own clinical practice demonstrating the challenges and benefits of this new technology.
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Affiliation(s)
- William G Newman
- Manchester Centre for Genomic Medicine, University of Manchester, Manchester, M13 9WL, UK.
| | - Graeme C Black
- Manchester Centre for Genomic Medicine, University of Manchester, Manchester, M13 9WL, UK.
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23
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Xue Y, Ankala A, Wilcox WR, Hegde MR. Solving the molecular diagnostic testing conundrum for Mendelian disorders in the era of next-generation sequencing: single-gene, gene panel, or exome/genome sequencing. Genet Med 2014; 17:444-51. [PMID: 25232854 DOI: 10.1038/gim.2014.122] [Citation(s) in RCA: 230] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 08/07/2014] [Indexed: 12/18/2022] Open
Abstract
Next-generation sequencing is changing the paradigm of clinical genetic testing. Today there are numerous molecular tests available, including single-gene tests, gene panels, and exome sequencing or genome sequencing. As a result, ordering physicians face the conundrum of selecting the best diagnostic tool for their patients with genetic conditions. Single-gene testing is often most appropriate for conditions with distinctive clinical features and minimal locus heterogeneity. Next-generation sequencing-based gene panel testing, which can be complemented with array comparative genomic hybridization and other ancillary methods, provides a comprehensive and feasible approach for heterogeneous disorders. Exome sequencing and genome sequencing have the advantage of being unbiased regarding what set of genes is analyzed, enabling parallel interrogation of most of the genes in the human genome. However, current limitations of next-generation sequencing technology and our variant interpretation capabilities caution us against offering exome sequencing or genome sequencing as either stand-alone or first-choice diagnostic approaches. A growing interest in personalized medicine calls for the application of genome sequencing in clinical diagnostics, but major challenges must be addressed before its full potential can be realized. Here, we propose a testing algorithm to help clinicians opt for the most appropriate molecular diagnostic tool for each scenario.
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Affiliation(s)
- Yuan Xue
- Emory Genetics Laboratory, Department of Human Genetics, Emory University, Atlanta, Georgia, USA
| | - Arunkanth Ankala
- Emory Genetics Laboratory, Department of Human Genetics, Emory University, Atlanta, Georgia, USA
| | - William R Wilcox
- Clinical Division, Department of Human Genetics, Emory University, Atlanta, Georgia, USA
| | - Madhuri R Hegde
- Emory Genetics Laboratory, Department of Human Genetics, Emory University, Atlanta, Georgia, USA
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24
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Kodera H, Ando N, Yuasa I, Wada Y, Tsurusaki Y, Nakashima M, Miyake N, Saitoh S, Matsumoto N, Saitsu H. Mutations in COG2 encoding a subunit of the conserved oligomeric golgi complex cause a congenital disorder of glycosylation. Clin Genet 2014; 87:455-60. [PMID: 24784932 DOI: 10.1111/cge.12417] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Revised: 04/28/2014] [Accepted: 04/28/2014] [Indexed: 10/25/2022]
Abstract
The conserved oligomeric Golgi (COG) complex is involved in intra-Golgi retrograde trafficking, and mutations in six of its eight subunits have been reported in congenital disorders of glycosylation (CDG). Here we report a patient showing severe acquired microcephaly, psychomotor retardation, seizures, liver dysfunction, hypocupremia, and hypoceruloplasminemia. Analysis of his serum glycoproteins revealed defects in both sialylation and galactosylation of glycan termini. Trio-based whole-exome sequencing identified two heterozygous mutations in COG2: a de novo frameshift mutation [c.701dup (p.Tyr234*)] and a missense mutation [c.1900T > G (p.Trp634Gly)]. Sequencing of cloned reverse-transcription polymerase chain reaction (RT-PCR) products revealed that both mutations were located on separate alleles, as expected, and that the mutant transcript harboring the frameshift mutation underwent degradation. The c.1900T > G (p.Trp634Gly) mutation is located in a domain highly conserved among vertebrates and was absent from both the public database and our control exomes. Protein expression of COG2, along with COG3 and COG4, was decreased in fibroblasts from the patient. Our data strongly suggest that these compound heterozygous mutations in COG2 are causative of CDG.
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Affiliation(s)
- H Kodera
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Kanazawa-ku, Yokohama, Japan
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25
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Ankala A, Hegde M. Genomic Technologies and the New Era of Genomic Medicine. J Mol Diagn 2014; 16:7-10. [DOI: 10.1016/j.jmoldx.2013.11.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 11/08/2013] [Accepted: 11/12/2013] [Indexed: 10/26/2022] Open
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