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Pan L, Qiu Y, Ye L, Li L, Huang Y, Mo W, Lin F. A clinical update of compound heterozygosity for hemoglobin Hekinan II [a27(B8)Glu-Asp; HBA1: c.84G>T] variant in China. Lab Med 2024:lmae023. [PMID: 38581097 DOI: 10.1093/labmed/lmae023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/08/2024] Open
Abstract
BACKGROUND Hemoglobin (Hb) Hekinan II (A27; Glu-Asp) is an α-chain variant, and its interaction with the common Southeast Asian (--SEA/) α-thalassemia (α-thal) deletion is rarely reported. This study provides a clinical update of Hb Hekinan II associated with (--SEA/) α-thal. METHODS A total of 11 simple heterozygotes and 20 composite heterozygotes for Hb Hekinan II and (--SEA/) α-thal were included based on molecular diagnosis. RESULTS Hb Hekinan II exhibited a significant increase in hemoglobin, mean corpuscular volume, and mean corpuscular hemoglobin content, but a decrease in red blood cell level compared with α+ thalassemia deletion. Compared with (--SEA/) α-thal, composite heterozygotes for Hb Hekinan II and (--SEA/) α-thal showed similar erythrocyte parameters. Both heterozygotes with and without (--SEA/) α-thal showed low Hb A2 level. Hb Hekinan II showed abnormal performance in high-performance liquid chromatography but not in capillary electrophoresis. CONCLUSION Hb Hekinan II is a benign Hb variant. The heterozygotes exhibit clinically asymptomatic coinheritance with (--SEA/) α-thal having comparable hematological phenotype to simple (--SEA/) α-thal. The combination of hematological and molecular analysis helped to improve the detection rate of this rare variant.
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Affiliation(s)
- Liqiu Pan
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
- Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning, China
| | - Yuling Qiu
- Guangxi Key Laboratory of Thalassemia Research, Guangxi Medical University, Nanning, China
| | - Lihua Ye
- Department of Clinical Laboratory, Laibin Maternal and Child Health Care Hospital, Laibin, China
| | - Linlin Li
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
- Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning, China
| | - Yuanyuan Huang
- Department of Clinical Laboratory, Liuzhou Maternal and Child Health Hospital, Liuzhou, China
| | - Wuning Mo
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
- Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning, China
| | - Faquan Lin
- Department of Clinical Laboratory, The First Affiliated Hospital of Guangxi Medical University, Nanning, China
- Key Laboratory of Clinical Laboratory Medicine of Guangxi Department of Education, Guangxi Medical University, Nanning, China
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Stadermann A, Haar M, Riecke A, Mayer T, Neumann C, Bauer A, Schulz A, Nagarathinam K, Gebauer N, Böhm S, Groß M, Grunert M, Müller M, Witte H. Late Onset of Primary Hemophagocytic Lymphohistiocytosis (HLH) with a Novel Constellation of Compound Heterozygosity Involving Two Missense Variants in the PRF1 Gene. Int J Mol Sci 2024; 25:2762. [PMID: 38474010 DOI: 10.3390/ijms25052762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2023] [Revised: 02/12/2024] [Accepted: 02/23/2024] [Indexed: 03/14/2024] Open
Abstract
Hemophagocytic lymphohistiocytosis (HLH) is a rare but in most cases life-threatening immune-mediated disease of the hematopoietic system frequently associated with hematologic neoplasms. Here, we report on a case in which we detected a novel constellation of two missense variants affecting the PRF1 gene, leading to de novo primary HLH. Diagnostics included a comprehensive clinical work-up and standard methods of hematopathology as well as extended molecular genomics based on polymerase chain reaction (PCR) reactions and the calculation of three-dimensional molecule reconstructions of PRF1. Subsequently, a comprehensive review of the literature was performed, which showed that this compound heterozygosity has not been previously described. The patient was a 20-year-old female. Molecular diagnostics revealed two heterozygous missense variants in the PRF1 gene (A91V and R104C) on exon 2. Apart from the finding of two inconclusive genetic variants, all clinical criteria defined by the HLH study group of Histiocyte Society were met at initial presentation. The final diagnosis was made in cooperation with the Consortium of German HLH-reference centers. Here, chemotherapy did not lead to sufficient sustained disease control. Therefore, the decision for allogenic hematopoietic stem cell transplantation (alloHSCT) was made. Hitherto, the duration of response was 6 months. Due to severe and unmanageable hepatic graft-versus-host disease (GvHD), the patient died. We report on a novel constellation of a compound heterozygosity containing two missense variants on exon 2 of the PRF1 gene. To the authors' best knowledge, this is the first presentation of a primary HLH case harboring this genomic constellation with late-onset clinical manifestation.
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Affiliation(s)
- Alina Stadermann
- Department of Hematology and Oncology, Bundeswehrkrankemhaus Ulm, Oberer Eselsberg 40, 89081 Ulm, Germany
| | - Markus Haar
- Department of Intensive Care Medicine, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20251 Hamburg, Germany
| | - Armin Riecke
- Department of Hematology and Oncology, Bundeswehrkrankemhaus Ulm, Oberer Eselsberg 40, 89081 Ulm, Germany
| | - Thomas Mayer
- Department of Hematology and Oncology, Bundeswehrkrankemhaus Ulm, Oberer Eselsberg 40, 89081 Ulm, Germany
| | - Christian Neumann
- Department of Hematology and Oncology, Bundeswehrkrankemhaus Ulm, Oberer Eselsberg 40, 89081 Ulm, Germany
| | - Arthur Bauer
- Department of Hematology and Oncology, Bundeswehrkrankemhaus Ulm, Oberer Eselsberg 40, 89081 Ulm, Germany
| | - Ansgar Schulz
- Department of Pediatric Medicine, University Hospital Ulm, Eythstraße 24, 89075 Ulm, Germany
| | - Kumar Nagarathinam
- Institute of Biochemistry, University of Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany
| | - Niklas Gebauer
- Department of Hematology and Oncology, University Hospital Schleswig-Holstein Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany
| | - Svea Böhm
- Institute for Immunodeficiency, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Straße 115, 79106 Freiburg, Germany
- Division of Pediatric Stem Cell Transplantation and Immunology, Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20246 Hamburg, Germany
| | - Miriam Groß
- Institute for Immunodeficiency, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Breisacher Straße 115, 79106 Freiburg, Germany
| | - Michael Grunert
- Department of Nuclear Medicine, Bundeswehrkrankenhaus Ulm, Oberer Eselsberg 40, 89081 Ulm, Germany
- Department of Nuclear Medicine, University Hospital Ulm, Albert-Einstein-Allee 23, 89081 Ulm, Germany
| | - Matthias Müller
- Department of Hematology and Oncology, Bundeswehrkrankemhaus Ulm, Oberer Eselsberg 40, 89081 Ulm, Germany
| | - Hanno Witte
- Department of Hematology and Oncology, Bundeswehrkrankemhaus Ulm, Oberer Eselsberg 40, 89081 Ulm, Germany
- Department of Hematology and Oncology, University Hospital Schleswig-Holstein Campus Lübeck, Ratzeburger Allee 160, 23538 Lübeck, Germany
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Felzen A, van Wessel DB, Gonzales E, Thompson RJ, Jankowska I, Shneider BL, Sokal E, Grammatikopoulos T, Kadaristiana A, Jacquemin E, Spraul A, Lipiński P, Czubkowski P, Rock N, Shagrani M, Broering D, Nicastro E, Kelly D, Nebbia G, Arnell H, Fischler B, Hulscher JB, Serranti D, Arikan C, Polat E, Debray D, Lacaille F, Goncalves C, Hierro L, Muñoz Bartolo G, Mozer-Glassberg Y, Azaz A, Brecelj J, Dezsőfi A, Calvo PL, Grabhorn E, Hartleif S, van der Woerd WJ, Kamath BM, Wang JS, Li L, Durmaz Ö, Kerkar N, Jørgensen MH, Fischer R, Jimenez-Rivera C, Alam S, Cananzi M, Laverdure N, Ferreira CT, Guerrero FO, Wang H, Sency V, Kim KM, Chen HL, de Carvalho E, Fabre A, Bernabeu JQ, Zellos A, Alonso EM, Sokol RJ, Suchy FJ, Loomes KM, McKiernan PJ, Rosenthal P, Turmelle Y, Horslen S, Schwarz K, Bezerra JA, Wang K, Hansen BE, Verkade HJ. Genotype-phenotype relationships of truncating mutations, p.E297G and p.D482G in bile salt export pump deficiency. JHEP Rep 2022; 5:100626. [PMID: 36687469 PMCID: PMC9852554 DOI: 10.1016/j.jhepr.2022.100626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 10/07/2022] [Accepted: 10/24/2022] [Indexed: 11/17/2022] Open
Abstract
Background & Aims Bile salt export pump (BSEP) deficiency frequently necessitates liver transplantation in childhood. In contrast to two predicted protein truncating mutations (PPTMs), homozygous p.D482G or p.E297G mutations are associated with relatively mild phenotypes, responsive to surgical interruption of the enterohepatic circulation (siEHC). The phenotype of patients with a compound heterozygous genotype of one p.D482G or p.E297G mutation and one PPTM has remained unclear. We aimed to assess their genotype-phenotype relationship. Methods From the NAPPED database, we selected patients with homozygous p.D482G or p.E297G mutations (BSEP1/1; n = 31), with one p.D482G or p.E297G, and one PPTM (BSEP1/3; n = 30), and with two PPTMs (BSEP3/3; n = 77). We compared clinical presentation, native liver survival (NLS), and the effect of siEHC on NLS. Results The groups had a similar median age at presentation (0.7-1.3 years). Overall NLS at age 10 years was 21% in BSEP1/3 vs. 75% in BSEP1/1 and 23% in BSEP3/3 (p <0.001). Without siEHC, NLS in the BSEP1/3 group was similar to that in BSEP3/3, but considerably lower than in BSEP1/1 (at age 10 years: 38%, 30%, and 71%, respectively; p = 0.003). After siEHC, BSEP1/3 and BSEP3/3 were associated with similarly low NLS, while NLS was much higher in BSEP1/1 (10 years after siEHC, 27%, 14%, and 92%, respectively; p <0.001). Conclusions Individuals with BSEP deficiency with one p.E297G or p.D482G mutation and one PPTM have a similarly severe disease course and low responsiveness to siEHC as those with two PPTMs. This identifies a considerable subgroup of patients who are unlikely to benefit from interruption of the enterohepatic circulation by either surgical or ileal bile acid transporter inhibitor treatment. Impact and implications This manuscript defines the clinical features and prognosis of individuals with BSEP deficiency involving the combination of one relatively mild and one very severe BSEP deficiency mutation. Until now, it had always been assumed that the mild mutation would be enough to ensure a relatively good prognosis. However, our manuscript shows that the prognosis of these patients is just as poor as that of patients with two severe mutations. They do not respond to biliary diversion surgery and will likely not respond to the new IBAT (ileal bile acid transporter) inhibitors, which have recently been approved for use in BSEP deficiency.
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Key Words
- ABCB11, ATP-binding cassette, sub-family B member 11
- ALT, alanine aminotransferase
- AST, aspartate aminotransferase
- BSEP
- BSEP, bile salt export pump
- ChiLDReN, Childhood Liver Disease Research Network
- GGT, gamma-glutamyltransferase
- HCC, hepatocellular carcinoma
- LTx, liver transplantation
- NAPPED, NAtural course and Prognosis of PFIC and Effect of biliary Diversion
- NLS, native liver survival
- PFIC2
- PFIC2, progressive familial intrahepatic cholestasis type 2
- PPTM, predicted protein truncating mutation
- REDCap, Research Electronic Data Capture
- TSB, total serum bilirubin
- UDCA, ursodeoxycholic acid
- compound heterozygosity
- genotype
- interruption of the enterohepatic circulation
- phenotype
- sBAs, serum bile acids
- siEHC, surgical interruption of the enterohepatic circulation
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Affiliation(s)
- Antonia Felzen
- Pediatric Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, the Netherlands
| | - Daan B.E. van Wessel
- Pediatric Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, the Netherlands
| | - Emmanuel Gonzales
- Pediatric Hepatology & Pediatric Liver Transplant Department, Centre de Référence de l'Atrésie des Voies Biliaires et des Cholestases Génétiques, Filière de Santé des Maladies Rares du Foie de l'enfant et de l'adulte, Assistance Publique-Hôpitaux de Paris, Faculté de Médecine Paris-Saclay, CHU Bicêtre, Paris, France,European Reference Network on Hepatological Diseases (ERN RARE-LIVER),INSERM, UMR-S 1193, Hepatinov, Université Paris-Saclay, Orsay, France
| | | | - Irena Jankowska
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Gastroenterology, Hepatology, Nutritional Disorders and Pediatrics, The Children’s Memorial Health Institute, Warsaw, Poland
| | - Benjamin L. Shneider
- Division of Pediatric Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA,Childhood Liver Disease Research Network (ChiLDReN)
| | - Etienne Sokal
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Pediatric Gastorenterology and Hepatology, Université Catholique de Louvain, Cliniques St Luc, Brussels, Belgium
| | | | | | - Emmanuel Jacquemin
- Pediatric Hepatology & Pediatric Liver Transplant Department, Centre de Référence de l'Atrésie des Voies Biliaires et des Cholestases Génétiques, Filière de Santé des Maladies Rares du Foie de l'enfant et de l'adulte, Assistance Publique-Hôpitaux de Paris, Faculté de Médecine Paris-Saclay, CHU Bicêtre, Paris, France,European Reference Network on Hepatological Diseases (ERN RARE-LIVER),INSERM, UMR-S 1193, Hepatinov, Université Paris-Saclay, Orsay, France
| | - Anne Spraul
- INSERM, UMR-S 1193, Hepatinov, Université Paris-Saclay, Orsay, France,Service de Biochemie, Bicêtre Hôspital, AP-HP, Université Paris-Sud, Paris-Saclay, Inserm UMR-S 1174, France
| | - Patryk Lipiński
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Gastroenterology, Hepatology, Nutritional Disorders and Pediatrics, The Children’s Memorial Health Institute, Warsaw, Poland
| | - Piotr Czubkowski
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Gastroenterology, Hepatology, Nutritional Disorders and Pediatrics, The Children’s Memorial Health Institute, Warsaw, Poland
| | - Nathalie Rock
- Pediatric Gastroenterology, Hepatology and Nutrition Unit, Division of Pediatric Specialties, Department of Pediatrics, Gynecology and Obstetrics, University Hospitals of Geneva, Switzerland
| | - Mohammad Shagrani
- Liver & SB Transplant & Hepatobiliary-Pancreatic Surgery, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia,Alfaisal University, College of Medicine, Riyadh, Saudi Arabia
| | - Dieter Broering
- Liver & SB Transplant & Hepatobiliary-Pancreatic Surgery, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia
| | - Emanuele Nicastro
- Pediatric Hepatology, Gastroenterology and Transplantation, ASST Papa Giovanni XXIII, Bergamo, Italy
| | - Deirdre Kelly
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Liver Unit, Birmingham Women’s and Children’s Hospital, Birmingham, United Kingdom
| | - Gabriella Nebbia
- Servizio Di Epatologia e Nutrizione Pediatrica, Fondazione Irccs Ca' Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Henrik Arnell
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Pediatric Gastroenterology Hepatology and Nutrition, Astrid Lindgren Children’s Hospital, Karolinska University Hospital and Karolinska Institutet, Stockholm, Sweden
| | - Björn Fischler
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Pediatric Gastroenterology Hepatology and Nutrition, Astrid Lindgren Children’s Hospital, Karolinska University Hospital and Karolinska Institutet, Stockholm, Sweden
| | - Jan B.F. Hulscher
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Pediatric Surgery, University Medical Center Groningen, Groningen, the Netherlands
| | - Daniele Serranti
- Pediatric and Liver Unit, Meyer Children’s University Hospital of Florence, Florence, Italy
| | - Cigdem Arikan
- Koc University School of Medicine, Pediatric GI and Hepatology Liver Transplantation Center, Kuttam System in Liver Medicine, Istanbul, Turkey
| | - Esra Polat
- Pediatric Gastroenterology, Sancaktepe Training and Research Hospital, Istanbul, Turkey
| | - Dominique Debray
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Gastroenterology-Hepatology-Nutrition Unit, APHP-Necker Enfants Malades University Hospital, Paris, France
| | - Florence Lacaille
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Gastroenterology-Hepatology-Nutrition Unit, APHP-Necker Enfants Malades University Hospital, Paris, France
| | - Cristina Goncalves
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Previously Coimbra University Hospital Center, Coimbra, Portugal, Now Pediatric Gastroenterology/Hepatology Center Lisbon, Portugal
| | - Loreto Hierro
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Service of Pediatric Hepatology and Transplantation, Children's Hospital La Paz, La Paz University Hospital, Madrid, Spain
| | - Gema Muñoz Bartolo
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Service of Pediatric Hepatology and Transplantation, Children's Hospital La Paz, La Paz University Hospital, Madrid, Spain
| | - Yael Mozer-Glassberg
- Institute of Gastroenterology, Nutrition and Liver Diseases, Schneider Children's Medical Center of Israel, Petah Tikva, Israel
| | - Amer Azaz
- Pediatric Gastroenterology, Hepatology and Nutrition, Sheikh Khalifa Medical City, Abu Dhabi, United Arab Emirates
| | - Jernej Brecelj
- Department of Gastroenterology, Hepatology and Nutrition, University Children's Hospital Ljubljana, and Department of Pediatrics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia,Department of Pediatrics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Antal Dezsőfi
- Department of Pediatrics, Semmelweis University, Budapest, Hungary
| | - Pier Luigi Calvo
- Pediatic Gastroenterology Unit, Regina Margherita Children's Hospital, Azienda Ospedaliera Città Della Salute e Della Scienza University Hospital, Turin, Italy
| | - Enke Grabhorn
- Pediatric Hepatology and Liver Transplantation, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Steffen Hartleif
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Pediatric Gastroenterology and Hepatology, University Children’s Hospital Tυ¨bingen, University Medical Center Tυ¨bingen, Tυ¨bingen, Germany
| | - Wendy J. van der Woerd
- Pediatric Gastroenterology, Hepatology and Nutrition, Wilhelmina Children's Hospital, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Binita M. Kamath
- Division of Pediatric Gastroenterology, Hepatology, and Nutrition, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA,Division of Gastroenterology, Hepatology and Nutrition, The Hospital for Sick Children and the University of Toronto, Toronto, Canada
| | - Jian-She Wang
- Children’s Hospital of Fudan University, Shanghai, China
| | - Liting Li
- Children’s Hospital of Fudan University, Shanghai, China
| | - Özlem Durmaz
- Department of Child Health and Diseases, Gastroenterology, Hepatology and Nutrition, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Nanda Kerkar
- Pediatric Gastroenterology, Hepatology and Nutrition, University of Rochester Medical Center, Rochester, NY, USA
| | - Marianne Hørby Jørgensen
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Department of Pediatrics and Adolescent Medicine, Rigshospitalet Copenhagen University Hospital, Copenhagen, Denmark
| | - Ryan Fischer
- Pediatric Gastroenterology, Hepatology and Nutrition, Children's Mercy Hospital, Kansas City, MO, USA
| | - Carolina Jimenez-Rivera
- Department of Pediatrics, Children's Hospital of Eastern Ontario, University of Ottawa, Ottawa, Canada
| | - Seema Alam
- Pediatric Hepatology, Institute of Liver and Biliary Sciences, New Delhi, India
| | - Mara Cananzi
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Unit of Pediatric Gastroenterology, Digestive Endoscopy, Hepatology and Care of the Child with Liver Transplantation, Department of Women’s and Children’s Health, University Hospital of Padova, Padova, Italy
| | - Noemie Laverdure
- Service de Gastroentérologie, Hépatologie et Nutrition Pédiatriques, Hospices Civils de Lyon, Hôpital Femme Mère Enfant, Lyon, France
| | | | - Felipe Ordoñez Guerrero
- Pediatric Gastroenterology and Hepatology, Fundación Cardioinfantil Instituto de Cardiologia, Bogotá, Colombia
| | - Heng Wang
- DDC Clinic - Center for Special Needs Children, Adolescent Medicine and Pediatrics, Middlefield, OH, USA
| | - Valerie Sency
- DDC Clinic - Center for Special Needs Children, Adolescent Medicine and Pediatrics, Middlefield, OH, USA
| | - Kyung Mo Kim
- Department of Pediatrics, Asan Medical Center Children's Hospital, Seoul, South Korea
| | - Huey-Ling Chen
- Division of Pediatric Gastroenterology, Hepatology and Nutrition, National Taiwan University Children's Hospital, Taipei, Taiwan
| | - Elisa de Carvalho
- Pediatric Gastroenterology and Hepatology, Brasília Children's Hospital, Brasilia, Brazil
| | - Alexandre Fabre
- INSERM, MMG, Aix Marseille University, Marseille, France,Service de Pédiatrie Multidisciplinaire, Timone Enfant, Marseille, France
| | - Jesus Quintero Bernabeu
- European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Pediatric Hepatology and Liver Transplant Unit, Hospital Universitari Vall d'Hebron, Barcelona, Spain
| | - Aglaia Zellos
- First Department of Pediatrics, Aghia Sophia Children’s Hospital, National and Kapodistrian University of Athens, Greece
| | - Estella M. Alonso
- Childhood Liver Disease Research Network (ChiLDReN),Division of Pediatric Gastroenterology, Hepatology and Nutrition, Ann & Robert H. Lurie Children's Hospital, Chicago, IL, USA
| | - Ronald J. Sokol
- Childhood Liver Disease Research Network (ChiLDReN),Section of Pediatric Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, CO, USA
| | - Frederick J. Suchy
- Childhood Liver Disease Research Network (ChiLDReN),Section of Pediatric Gastroenterology, Hepatology and Nutrition, Department of Pediatrics, Children's Hospital Colorado, University of Colorado School of Medicine, Aurora, CO, USA
| | - Kathleen M. Loomes
- Childhood Liver Disease Research Network (ChiLDReN),Division of Gastroenterology, Hepatology and Nutrition, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Patrick J. McKiernan
- Childhood Liver Disease Research Network (ChiLDReN),Department of Pediatric Gastroenterology and Hepatology, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Philip Rosenthal
- Childhood Liver Disease Research Network (ChiLDReN),Department of Pediatrics and Surgery, UCSF Benioff Children's Hospital, University of California San Francisco School of Medicine, San Francisco, CA, USA
| | - Yumirle Turmelle
- Childhood Liver Disease Research Network (ChiLDReN),Section of Hepatology, Department of Pediatrics, St. Louis Children's Hospital, Washington University School of Medicine, St. Louis, MO, USA
| | - Simon Horslen
- Childhood Liver Disease Research Network (ChiLDReN),Department of Pediatric Gastroenterology and Hepatology, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, PA, USA
| | - Kathleen Schwarz
- Childhood Liver Disease Research Network (ChiLDReN),Division of Pediatric Gastroenterology, University of California San Diego, Rady Children's Hospital San Diego, CA, USA
| | - Jorge A. Bezerra
- Childhood Liver Disease Research Network (ChiLDReN),Division of Gastroenterology, Hepatology and Nutrition, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Kasper Wang
- Childhood Liver Disease Research Network (ChiLDReN),Division of General Pediatric Surgery, Children's Hospital Los Angeles, Los Angeles, CA, USA
| | - Bettina E. Hansen
- Toronto Center for Liver Disease, University Health Network, Toronto, Canada,IHPME, University of Toronto, Toronto, Canada,Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, the Netherlands
| | - Henkjan J. Verkade
- Pediatric Gastroenterology and Hepatology, University Medical Center Groningen, University of Groningen, the Netherlands,European Reference Network on Hepatological Diseases (ERN RARE-LIVER),Corresponding author. Address: Pediatric Gastroenterology & Hepatology, Department of Pediatrics, Beatrix Children’s Hospital, University Medical Center Groningen, University of Groningen, PO Box 30.001, 9700 RB Groningen, the Netherlands. Tel.: +31 50 3614147, fax: +31 50 361 1704
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4
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Berdyński M, Ludwiczak J, Barczak A, Barcikowska-Kotowicz M, Kuźma-Kozakiewicz M, Dunin-Horkawicz S, Żekanowski C, Borzemska B. TREM2 Gene Compound Heterozygosity in Neurodegenerative Disorders. J Alzheimers Dis 2022; 89:1211-1219. [PMID: 36031890 DOI: 10.3233/jad-220210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Homozygous variants of the TREM2 and TYROBP genes have been shown to be causative for multiple bone cysts and neurodegeneration leading to progressive dementia (NHD, Nasu-Hakola disease). OBJECTIVE To determine if biallelic variants of these genes and/or oligogenic inheritance could be responsible for a wider spectrum of neurodegenerative conditions. METHODS We analyzed 52 genes associated with neurodegenerative disorders using targeted next generation sequencing in a selected group of 29 patients (n = 14 Alzheimer's disease, n = 8 frontotemporal dementia, n = 7 amyotrophic lateral sclerosis) carrying diverse already determined rare variants in exon 2 of TREM2. Molecular modeling was used to get an insight into the potential effects of the mutation. RESULTS We identified a novel mutation c.401_406delinsTCTAT; p.(Asp134Valfs*55) in exon 3 of TREM2 in an Alzheimer's disease patient also carrying the p.Arg62His TREM2 variant. Molecular modeling revealed that the identified mutation prevents anchoring of the TREM2 protein in the membrane, leaving the core of the Ig-like domain intact. CONCLUSION Our results expand the spectrum of neurodegenerative diseases, where the carriers of biallelic mutations in TREM2 have been described for Alzheimer's disease, and highlight the impact of variant burden in other genes on phenotypic heterogeneity.
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Affiliation(s)
- Mariusz Berdyński
- Department of Neurogenetics and Functional Genomics, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Jan Ludwiczak
- Laboratory of Structural Bioinformatics, Centre of New Technologies, University of Warsaw, Warsaw, Poland.,Laboratory of Bioinformatics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland
| | - Anna Barczak
- Rare Diseases Research Platform, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | | | - Magdalena Kuźma-Kozakiewicz
- Neurodegenerative Diseases Research Group, Medical University of Warsaw, Warsaw, Poland.,Department of Neurology, Medical University of Warsaw, Warsaw, Poland
| | - Stanisław Dunin-Horkawicz
- Laboratory of Structural Bioinformatics, Centre of New Technologies, University of Warsaw, Warsaw, Poland
| | - Cezary Żekanowski
- Department of Neurogenetics and Functional Genomics, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
| | - Beata Borzemska
- Department of Neurogenetics and Functional Genomics, Mossakowski Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland
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5
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Villarreal-Molina T, García-Ordóñez GP, Reyes-Quintero ÁE, Domínguez-Pérez M, Jacobo-Albavera L, Nava S, Carnevale A, Medeiros-Domingo A, Iturralde P. Clinical Spectrum of SCN5A Channelopathy in Children with Primary Electrical Disease and Structurally Normal Hearts. Genes (Basel) 2021; 13:16. [PMID: 35052356 DOI: 10.3390/genes13010016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/11/2021] [Accepted: 12/18/2021] [Indexed: 12/19/2022] Open
Abstract
Sodium voltage-gated channel α subunit 5 (SCN5A)-mutations may cause an array of arrhythmogenic syndromes most frequently as an autosomal dominant trait, with incomplete penetrance, variable expressivity and male predominance. In the present study, we retrospectively describe a group of Mexican patients with SCN5A-disease causing variants in whom the onset of symptoms occurred in the pediatric age range. The study included 17 patients with clinical diagnosis of primary electrical disease, at least one SCN5A pathogenic or likely pathogenic mutation and age of onset <18 years, and all available first- and second-degree relatives. Fifteen patients (88.2%) were male, and sixteen independent variants were found (twelve missense, three truncating and one complex inframe deletion/insertion). The frequency of compound heterozygosity was remarkably high (3/17, 17.6%), with early childhood onset and severe disease. Overall, 70.6% of pediatric patients presented with overlap syndrome, 11.8% with isolated sick sinus syndrome, 11.8% with isolated Brugada syndrome (BrS) and 5.9% with isolated type 3 long QT syndrome (LQTS). A total of 24/45 SCN5A mutation carriers were affected (overall penetrance 53.3%), and penetrance was higher in males (63.3%, 19 affected/30 mutation carriers) than in females (33.3%, 5 affected/15 carriers). In conclusion, pediatric patients with SCNA-disease causing variants presented mainly as overlap syndrome, with predominant loss-of-function phenotypes of sick sinus syndrome (SSS), progressive cardiac conduction disease (PCCD) and ventricular arrhythmias.
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6
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Hu S, Zhang H, Liu Y, Liu M, Li J, Liao S. Whole-exome sequencing of de novo genetic variants in a Chinese family with a sporadic case of congenital nonsyndromic hearing loss. F1000Res 2021; 10:61. [PMID: 34567527 PMCID: PMC8422347 DOI: 10.12688/f1000research.27739.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/18/2021] [Indexed: 02/05/2023] Open
Abstract
Background: We examined the genetic variants of a Chinese family with a 22-month-old infant with sporadic non-syndromic sensorineural hearing loss (NSHL). Methods: The whole-exome sequence data in the family, especially the de novo variants presented in the patient, were analyzed and the effect of the disease-causing genetic variants on the protein expression level and cellular localization were examined by cell-based functional assay. Results: The infant had no known NSHL-causing variants, except two compound heterozygous variants in connexin26 gene GJB2; one was the c.79G>A, c.341A>G haplotype from the asymptomatic mother who was benign, and the other was a de novo pathogenic c.262G>C (p.A88P). In vitro, GJB2 with c.262G>C was weakly expressed and displayed a punctate distribution in the cytoplasm and cytomembrane, while wild type GJB2 was robustly expressed in the cytomembrane. We deduced that the de novo pathogenic GJB2 c.262G>C exacerbated loss-of-function in the context of leaky variants c.79G>A, c.341A>G in the patient. Interestingly, further analysis of exome sequences revealed that the occurrence of de novo pathogenic variants in the infant was frequent. Among the total~47,000 variants, 143 were de novo in the patient, whereas among all 74 variants predicted to be pathogenic/likely pathogenic, 21 were heterozygous and two were homozygous de novo. The occurrence rate of de novo deleterious variants was much higher (31.1%, 23/74) than that in total (0.34%, 143/47,000). It is notable that most genes with de novo deleterious variants were environment-sensitive, such as GJB2, MNK1, MNK2, MUC4, RAD21 and DNA copy number variations. Conclusions: The full picture of genetic variants in the exome might help us to interpret the NSHL-causing variants. More research is needed into the causes of de novo deleterious variants and gene-environment interactions in congenital NSHL.
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Affiliation(s)
- Sijing Hu
- Diabetes Center & Institute of Organ Transplantation, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China, 610072, China
| | - Hao Zhang
- Department of Medical Genetics and Division of Morbid Genomics, State Key Laboratory of Biotherapy, West China Hospital,, West China Medical School, Sichuan University,, Chengdu, China, 610041, China
| | - Yunqiang Liu
- Department of Medical Genetics and Division of Morbid Genomics, State Key Laboratory of Biotherapy, West China Hospital,, West China Medical School, Sichuan University,, Chengdu, China, 610041, China
| | - Mohan Liu
- Department of Medical Genetics and Division of Morbid Genomics, State Key Laboratory of Biotherapy, West China Hospital,, West China Medical School, Sichuan University,, Chengdu, China, 610041, China
| | - Jingjing Li
- Diabetes Center & Institute of Organ Transplantation, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China, 610072, China
| | - Shunyao Liao
- Diabetes Center & Institute of Organ Transplantation, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China, 610072, China
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7
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Hu S, Zhang H, Liu Y, Liu M, Li J, Liao S. Whole-exome sequencing of de novo genetic variants in a Chinese family with a sporadic case of congenital nonsyndromic hearing loss. F1000Res 2021; 10:61. [PMID: 34567527 PMCID: PMC8422347 DOI: 10.12688/f1000research.27739.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/06/2021] [Indexed: 04/04/2024] Open
Abstract
Background: We examined the genetic variants of a Chinese family with a 22-month-old infant with sporadic non-syndromic sensorineural hearing loss (NSHL). Methods: The whole-exome sequence data in the family, especially the de novo variants presented in the patient, were analyzed and the effect of the disease-causing genetic variants on the protein expression level and cellular localization were examined by cell-based functional assay. Results: The infant had no known NSHL-causing variants, except two compound heterozygous variants in connexin26 gene GJB2; one was the c.79G>A, c.341A>G haplotype from the asymptomatic mother which was benign, and the other was a de novo pathogenic c.262G>C (p.A88P). In vitro, GJB2 with c.262G>C was weakly expressed and displayed a punctate distribution in the cytoplasm and cytomembrane, while wild type GJB2 was robustly expressed in the cytomembrane. We deduced that the de novo pathogenic GJB2 c.262G>C exacerbated loss-of-function in the context of leaky variants c.79G>A, c.341A>G in the patient. Interestingly, further analysis of exome sequences revealed that the occurrence of de novo pathogenic variants in the infant was frequent. Among the total~47,000 variants, 143 were de novo in the patient, whereas among all 74 variants predicted to be pathogenic/likely pathogenic, 21 were heterozygous and two were homozygous de novo. The occurrence rate of de novo deleterious variants was much higher (31.1%, 23/74) than that in total (0.34%, 143/47,000). It is notable that most genes with de novo deleterious variants were environment-sensitive, such as GJB2, MNK1, MNK2, MUC4, RAD21 and DNA copy number variations. Conclusions: The full picture of genetic variants in the exome might help us to interpret the NSHL-causing variants. More research is needed into the causes of de novo deleterious variants and gene-environment interactions in congenital NSHL.
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Affiliation(s)
- Sijing Hu
- Diabetes Center & Institute of Organ Transplantation, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China, 610072, China
| | - Hao Zhang
- Department of Medical Genetics and Division of Morbid Genomics, State Key Laboratory of Biotherapy, West China Hospital,, West China Medical School, Sichuan University,, Chengdu, China, 610041, China
| | - Yunqiang Liu
- Department of Medical Genetics and Division of Morbid Genomics, State Key Laboratory of Biotherapy, West China Hospital,, West China Medical School, Sichuan University,, Chengdu, China, 610041, China
| | - Mohan Liu
- Department of Medical Genetics and Division of Morbid Genomics, State Key Laboratory of Biotherapy, West China Hospital,, West China Medical School, Sichuan University,, Chengdu, China, 610041, China
| | - Jingjing Li
- Diabetes Center & Institute of Organ Transplantation, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China, 610072, China
| | - Shunyao Liao
- Diabetes Center & Institute of Organ Transplantation, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, China, 610072, China
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8
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Nijak A, Labro AJ, De Wilde H, Dewals W, Peigneur S, Tytgat J, Snyders D, Sieliwonczyk E, Simons E, Van Craenenbroeck E, Schepers D, Van Laer L, Saenen J, Loeys B, Alaerts M. Compound Heterozygous SCN5A Mutations in Severe Sodium Channelopathy With Brugada Syndrome: A Case Report. Front Cardiovasc Med 2020; 7:117. [PMID: 32850980 PMCID: PMC7396896 DOI: 10.3389/fcvm.2020.00117] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 06/04/2020] [Indexed: 12/16/2022] Open
Abstract
Aims: Brugada syndrome (BrS) is an inherited cardiac arrhythmia with an increased risk for sudden cardiac death (SCD). About 20% of BrS cases are explained by mutations in the SCN5A gene, encoding the main cardiac sodium Nav1.5 channel. Here we present a severe case of cardiac sodium channelopathy with BrS caused by SCN5A compound heterozygous mutations. We performed a genetic analysis of SCN5A in a male proband who collapsed during cycling at the age of 2 years. Because of atrial standstill, he received a pacemaker, and at the age of 3 years, he experienced a collapse anew with left-sided brain stroke. A later ECG taken during a fever unmasked a characteristic BrS type-1 pattern. The functional effect of the detected genetic variants was investigated. Methods and Results: Next-generation sequencing allowed the detection of two SCN5A variants in trans: c.4813+3_4813+6dupGGGT-a Belgian founder mutation-and c.4711 T>C, p.Phe1571Leu. A familial segregation analysis showed the presence of the founder mutation in the proband's affected father and paternal aunt and the de novo occurrence of the p.Phe1571Leu. The functional effect of the founder mutation was previously described as a loss-of-function. We performed a functional analysis of the p.Phe571Leu variant in HEK293 cells alone or co-expressed with the β1-subunit. Compared to the SCN5A wild type, p.Phe1571Leu displayed a hyperpolarizing shift in the voltage dependence of inactivation (loss-of-function), while the activation parameters were unaffected. Using the peptide toxin nemertide α-1, the variant's loss-of-function effect could be restored due to a toxin-dependent reduction of channel inactivation. Conclusion: This is the first report providing support for the pathogenicity of the p.Phe1571Leu SCN5A variant which, together with the c.4813+3_4813+6dupGGGT founder mutation, explains the severity of the phenotype of cardiac sodium channelopathy with BrS in the presented case.
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Affiliation(s)
- Aleksandra Nijak
- Center of Medical Genetics, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Alain J Labro
- Laboratory of Molecular, Cellular and Network Excitability, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Hans De Wilde
- Department of Paediatric Cardiology, Antwerp University Hospital, Antwerp, Belgium.,Department of Invasive Cardiology and Electrophysiology, Ghent University Hospital, Ghent, Belgium
| | - Wendy Dewals
- Department of Paediatric Cardiology, Antwerp University Hospital, Antwerp, Belgium
| | - Steve Peigneur
- Toxicology and Pharmacology, University of Leuven (KU Leuven), Leuven, Belgium
| | - Jan Tytgat
- Toxicology and Pharmacology, University of Leuven (KU Leuven), Leuven, Belgium
| | - Dirk Snyders
- Laboratory of Molecular, Cellular and Network Excitability, Department of Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Ewa Sieliwonczyk
- Center of Medical Genetics, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Eline Simons
- Center of Medical Genetics, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | | | - Dorien Schepers
- Center of Medical Genetics, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Lut Van Laer
- Center of Medical Genetics, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Johan Saenen
- Department of Cardiology, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
| | - Bart Loeys
- Center of Medical Genetics, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium.,Department of Human Genetics, Radboud University Medical Centre, Nijmegen, Netherlands
| | - Maaike Alaerts
- Center of Medical Genetics, Antwerp University Hospital, University of Antwerp, Antwerp, Belgium
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9
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Abstract
A compound heterozygous (CH) variant is a type of germline variant that occurs when each parent donates one alternate allele and these alleles are located at different loci within the same gene. Pathogenic germline variants have been identified for some pediatric cancer types but in most studies, CH variants are overlooked. Thus, the prevalence of pathogenic CH variants in most pediatric cancer types is unknown. We identified 26 studies (published between 1999 and 2019) that identified a CH variant in at least one pediatric cancer patient. These studies encompass 21 cancer types and have collectively identified 25 different genes in which a CH variant occurred. However, the sequencing methods used and the number of patients and genes evaluated in each study were highly variable across the studies. In addition, methods for assessing pathogenicity of CH variants varied widely and were often not reported. In this review, we discuss technologies and methods for identifying CH variants, provide an overview of studies that have identified CH variants in pediatric cancer patients, provide insights into future directions in the field, and give a summary of publicly available pediatric cancer sequencing data. Although considerable insights have been gained over the last 20 years, much has yet to be learned about the involvement of CH variants in pediatric cancers. In future studies, larger sample sizes, more pediatric cancer types, and better pathogenicity assessment and filtering methods will be needed to move this field forward.
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Affiliation(s)
- Dustin B Miller
- Department of Biology, Brigham Young University, Provo, UT, United States
| | - Stephen R Piccolo
- Department of Biology, Brigham Young University, Provo, UT, United States
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10
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Xu X, Yang X, Su Z, Wang H, Li X, Sun C, Wang W, Chen Y, Zhang C, Zhang H, Jin F, Zheng J. Identification of Novel Compound Heterozygous Mutations in the GAN Gene of a Chinese Patient Diagnosed With Giant Axonal Neuropathy. Front Neurosci 2020; 14:85. [PMID: 32158379 PMCID: PMC7052293 DOI: 10.3389/fnins.2020.00085] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 01/21/2020] [Indexed: 12/24/2022] Open
Abstract
Giant axonal neuropathy (GAN) is a very rare autosomal recessive disorder characterized by abnormally large and dysfunctional neuronal axons. Mutations in the GAN gene have been identified as the cause of this disorder. In this report, we performed a detailed phenotypic assessment of a Chinese patient with GAN. An array-based exon capture test and targeted next-generation sequencing were used to detect the suspected mutation sites. Compound heterozygous mutations of p.S79L (c.236C > T) in the BTB domain and p.T489S (c.1466C > G) in the kelch domain were identified in the proband’s genome. S79L was a known mutation, and T489S was reported for the first time. The p.S79L and p.T489S were confirmed in the proband’s mother and father, respectively. Both mutations were located in highly conserved regions and affected the predicted protein crystal structures. The proband’s sural biopsy revealed the classical GAN phenotype of swollen axons filled with closely packed neurofilaments. The combined application of the next-generation sequencing platform and bioinformatics analyses was an effective method for diagnosing GAN. The novel compound mutations of S79L and T489S in the GAN gene were likely the cause of the patient’s GAN symptoms. Our findings enrich the spectrum of mutations associated with this rare type of axonopathy.
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Affiliation(s)
- Xiaomin Xu
- Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, China.,Wenzhou City Key Laboratory of Gynecology and Obstetrics, Wenzhou, China
| | - Xiaokai Yang
- Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, China
| | - Zhongliang Su
- Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, China
| | - Hai Wang
- Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, China.,Wenzhou City Key Laboratory of Gynecology and Obstetrics, Wenzhou, China
| | - Xiaoqing Li
- Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, China.,Wenzhou City Key Laboratory of Gynecology and Obstetrics, Wenzhou, China
| | - Congcong Sun
- Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, China.,Wenzhou City Key Laboratory of Gynecology and Obstetrics, Wenzhou, China
| | - Wenhuan Wang
- Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, China.,Wenzhou City Key Laboratory of Gynecology and Obstetrics, Wenzhou, China
| | - Yao Chen
- Hangzhou Fuyang Women and Children Hospital, Fuyang, China
| | - Chenhui Zhang
- Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, China.,Wenzhou City Key Laboratory of Gynecology and Obstetrics, Wenzhou, China
| | - Hongping Zhang
- Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, China
| | - Fan Jin
- Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jiayong Zheng
- Wenzhou People's Hospital, Wenzhou Maternal and Child Health Care Hospital, The Third Clinical Institute Affiliated to Wenzhou Medical University, Wenzhou, China.,Wenzhou City Key Laboratory of Gynecology and Obstetrics, Wenzhou, China
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11
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Zhang W, Wang X, Duan W, Xu A, Zhao X, Huang J, You H, Brissot P, Ou X, Jia J. HFE-Related Hemochromatosis in a Chinese Patient: The First Reported Case. Front Genet 2020; 11:77. [PMID: 32153640 PMCID: PMC7048005 DOI: 10.3389/fgene.2020.00077] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 01/23/2020] [Indexed: 01/04/2023] Open
Abstract
HFE-related Hemochromatosis is the most common genetic iron overload disease in European populations, particularly of Nordic or Celtic ancestry. It is reported that the HFE p.C282Y mutation is present in 1/10 people of northern European descent, resulting in one in two hundred people will be homozygous. However, the HFE p.C282Y heterozygosity is virtually absent among East Asians, including Japanese, Koreans, and Chinese. In this article, we report a case of HFE-related hemochromatosis caused by compound heterozygosity HFE p.C282Y/p.R71X. This is the first report of hemochromatosis associated with HFE p.C282Y mutation in China.
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Affiliation(s)
- Wei Zhang
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China.,Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China.,Liver Research Center, National Clinical Research Center for Digestive Diseases, Beijing, China
| | - Xiaoming Wang
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China.,Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China.,Liver Research Center, National Clinical Research Center for Digestive Diseases, Beijing, China
| | - Weijia Duan
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China.,Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China.,Liver Research Center, National Clinical Research Center for Digestive Diseases, Beijing, China
| | - Anjian Xu
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China.,Liver Research Center, National Clinical Research Center for Digestive Diseases, Beijing, China.,Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Xinyan Zhao
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China.,Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China.,Liver Research Center, National Clinical Research Center for Digestive Diseases, Beijing, China
| | - Jian Huang
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China.,Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China.,Liver Research Center, National Clinical Research Center for Digestive Diseases, Beijing, China.,Experimental Center, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Hong You
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China.,Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China.,Liver Research Center, National Clinical Research Center for Digestive Diseases, Beijing, China
| | - Pierre Brissot
- Institut NuMeCan, InsermU-1241, University of Rennes1, Rennes, France
| | - Xiaojuan Ou
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China.,Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China.,Liver Research Center, National Clinical Research Center for Digestive Diseases, Beijing, China
| | - Jidong Jia
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing Key Laboratory of Translational Medicine on Liver Cirrhosis, Beijing, China.,Clinical Research Center for Rare Liver Diseases, Capital Medical University, Beijing, China.,Liver Research Center, National Clinical Research Center for Digestive Diseases, Beijing, China
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12
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Spieler D, Velayos-Baeza A, Mühlbäck A, Castrop F, Maegerlein C, Slotta-Huspenina J, Bader B, Haslinger B, Danek A. Identification of two compound heterozygous VPS13A large deletions in chorea-acanthocytosis only by protein and quantitative DNA analysis. Mol Genet Genomic Med 2020; 8:e1179. [PMID: 32056394 PMCID: PMC7507471 DOI: 10.1002/mgg3.1179] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 01/09/2020] [Accepted: 01/30/2020] [Indexed: 01/04/2023] Open
Abstract
Background Chorea‐acanthocytosis (ChAc; OMIM #200150) is a rare autosomal recessive condition with onset in early adulthood that is caused by mutations in the vacuolar protein sorting 13A (VPS13A) gene encoding chorein. Several diagnostic genomic DNA (gDNA) sequencing approaches are widely used. However, their limitations appear not to be acknowledged thoroughly enough. Methods Clinically, we deployed magnetic resonance imaging, blood smear analysis, and clinical chemistry for the index patient's characterization. The molecular analysis of the index patient next to his parents covered genomic DNA (gDNA) sequencing approaches, RNA/cDNA sequencing, and chorein specific Western blot. Results We report a 33‐year‐old male patient without functional protein due to compound heterozygosity for two VPS13A large deletions of 1168 and 1823 base pairs (bp) affecting, respectively, exons 8 and 9, and exon 13. To our knowledge, this represents the first ChAc case with two compound heterozygous large deletions identified so far. Of note, standard genomic DNA (gDNA) Sanger sequencing approaches alone yielded false negative findings. Conclusion Our case demonstrates the need to carry out detection of chorein in patients suspected of having ChAc as a helpful and potentially decisive tool to establish diagnosis. Furthermore, the course of the molecular analysis in this case discloses diagnostic pitfalls in detecting some variations, such as deletions, using only standard genomic DNA (gDNA) Sanger sequencing approaches and exemplifies alternative methods, such as RNA/cDNA sequencing or qRT‐PCR analysis, necessary to avoid false negative results.
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Affiliation(s)
- Derek Spieler
- Department of Psychosomatic Medicine and Psychotherapy, Center for Mental Health, Faculty of Medicine, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany.,Institute of Epidemiology, Mental Health Research Unit, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany.,Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | | | - Alžbeta Mühlbäck
- kbo-Isar-Amper-Klinikum Taufkirchen (Vils), Taufkirchen (Vils), Germany.,Department of Neurology and Centre of Clinical Neuroscience, First Faculty of Medicine, Charles University and General University Hospital Prague, Prague, Czech Republic
| | - Florian Castrop
- Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Christian Maegerlein
- Department of Neuroradiology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Julia Slotta-Huspenina
- Institut für Allgemeine Pathologie und Pathologische Anatomie der Technischen Universität München, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Benedikt Bader
- Neurologische Klinik und Poliklinik, Ludwigs-Maximilians Universität München, Munich, Germany
| | - Bernhard Haslinger
- Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Adrian Danek
- Neurologische Klinik und Poliklinik, Ludwigs-Maximilians Universität München, Munich, Germany
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13
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Bossi G, Errichiello E, Zuffardi O, Marone P, Monzillo V, Barbarini D, Vergori A, Bassi LA, Rispoli GA, De Amici M, Zecca M. Disseminated Mycobacterium Avium Infection in a Child with Complete Interferon-γ Receptor 1 Deficiency due to Compound Heterozygosis of IFNGR1 for a Subpolymorphic Copy Number Variation and a Novel Splice-Site Variant. J Pediatr Genet 2019; 9:186-192. [PMID: 32714620 DOI: 10.1055/s-0039-1700803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Accepted: 09/25/2019] [Indexed: 01/10/2023]
Abstract
Complete interferon-γ receptor 1 deficiency is a monogenic primary immunodeficiency caused by IFNGR1 germline defects, with autosomal dominant or recessive inheritance, which results in invasive mycobacterial diseases with varying degrees of severity. Most of the autosomal recessive IFNGR1 mutations are homozygous loss-of-function single-nucleotide variants, whereas large genomic deletions and compound heterozygosity have been very rarely reported. Herein we describe the clinical presentation, diagnosis, and successful treatment with hematopoietic stem cell transplantation of a child with disseminated Mycobacterium avium infection due to compound heterozygosity for a subpolymorphic copy number variation and a novel splice-site variant.
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Affiliation(s)
- Grazia Bossi
- Department of Pediatrics, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
| | | | - Orsetta Zuffardi
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Piero Marone
- Microbiology and Virology Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
| | - Vincenzina Monzillo
- Microbiology and Virology Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
| | - Daniela Barbarini
- Microbiology and Virology Unit, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
| | - Antonio Vergori
- Department of Pediatrics, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
| | - Lorenzo Andrea Bassi
- Department of Pediatrics, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
| | - Gaetana Anna Rispoli
- Department of Radiology, US Pediatric Radiology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
| | - Mara De Amici
- Immuno-Allergology and Clinical Chemistry Laboratory, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
| | - Marco Zecca
- Pediatric Hematology-Oncology, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo, Pavia, Italy
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14
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Castronovo P, Baccarin M, Ricciardello A, Picinelli C, Tomaiuolo P, Cucinotta F, Frittoli M, Lintas C, Sacco R, Persico AM. Phenotypic spectrum of NRXN1 mono- and bi-allelic deficiency: A systematic review. Clin Genet 2019; 97:125-137. [PMID: 30873608 DOI: 10.1111/cge.13537] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Revised: 03/01/2019] [Accepted: 03/10/2019] [Indexed: 01/13/2023]
Abstract
Neurexins are presynaptic cell adhesion molecules critically involved in synaptogenesis and vesicular neurotransmitter release. They are encoded by three genes (NRXN1-3), each yielding a longer alpha (α) and a shorter beta (β) transcript. Deletions spanning the promoter and the initial exons of the NRXN1 gene, located in chromosome 2p16.3, are associated with a variety of neurodevelopmental, psychiatric, neurological and neuropsychological phenotypes. We have performed a systematic review to define (a) the clinical phenotypes most associated with mono-allelic exonic NRXN1 deletions, and (b) the phenotypic features of NRXN1 bi-allelic deficiency due to compound heterozygous deletions/mutations. Clinically, three major conclusions can be drawn: (a) incomplete penetrance and pleiotropy do not allow reliable predictions of clinical outcome following prenatal detection of mono-allelic exonic NRXN1 deletions. Newborn carriers should undergo periodic neuro-behavioral observations for the timely detection of warning signs and the prescription of early behavioral intervention; (b) the presence of additional independent genetic risk factors should always be sought, as they may influence prognosis; (c) children with exonic NRXN1 deletions displaying early-onset, severe psychomotor delay in the context of a Pitt-Hopkins-like syndrome 2 phenotype, should undergo DNA sequencing of the spared NRXN1 allele in search for mutations or very small insertions/deletions.
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Affiliation(s)
- Paola Castronovo
- Laboratory for Pervasive Developmental Disorders, Mafalda Luce Center, Milan, Italy
| | - Marco Baccarin
- Laboratory for Pervasive Developmental Disorders, Mafalda Luce Center, Milan, Italy
| | - Arianna Ricciardello
- Interdepartmental Program "Autism 0-90", "Gaetano Martino" University Hospital, University of Messina, Messina, Italy
| | - Chiara Picinelli
- Laboratory for Pervasive Developmental Disorders, Mafalda Luce Center, Milan, Italy
| | - Pasquale Tomaiuolo
- Laboratory for Pervasive Developmental Disorders, Mafalda Luce Center, Milan, Italy
| | - Francesca Cucinotta
- Interdepartmental Program "Autism 0-90", "Gaetano Martino" University Hospital, University of Messina, Messina, Italy
| | - Myriam Frittoli
- Laboratory for Pervasive Developmental Disorders, Mafalda Luce Center, Milan, Italy
| | - Carla Lintas
- Service for Neurodevelopmental Disorders & Laboratory of Molecular Psychiatry and Neurogenetics, University "Campus Bio-Medico", Rome, Italy
| | - Roberto Sacco
- Service for Neurodevelopmental Disorders & Laboratory of Molecular Psychiatry and Neurogenetics, University "Campus Bio-Medico", Rome, Italy
| | - Antonio M Persico
- Interdepartmental Program "Autism 0-90", "Gaetano Martino" University Hospital, University of Messina, Messina, Italy
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15
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Jha AN, Mishra H, Verma HK, Pandey I, Lakkakula BVKS. Compound Heterozygosity of β-Thalassemia and the Sickle Cell Hemoglobin in Various Populations of Chhattisgarh State, India. Hemoglobin 2018; 42:84-90. [PMID: 30200838 DOI: 10.1080/03630269.2018.1483946] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Hemoglobinopathies evolved as a protective mechanism against malaria, which exhibit selective advantage in the heterozygous state. However, in a homozygous recessive condition, it poses a serious socioeconomic burden. Sickle cell anemia is an autosomal recessive hemoglobinopathy associated with erythrocytes sickling, vaso-occlusive crisis (VOC), as well as multi-organ failure and death. The coinheritance of other hemoglobinopathies is known to substantially modulate the clinical manifestation of sickle cell anemia. In the present study, we aimed to analyze the coinheritance of β-thalassemia (β-thal) in Hb S (HBB: c.20A>T) patients. The study includes 918 sickle cell anemia patients from 10 ethnic populations of Chhattisgarh State, India. Complete blood counts (CBCs) and hemoglobin (Hb) high performance liquid chromatography (HPLC) fractionation data were collected from patient record books. We observed Hb S-β-thal in all the analyzed populations. Interestingly, high frequencies of Hb S-β-thal have been observed in Satnami (53.8%), Rawat (47.1%), Gond (35.1%) and Panika (30.6%) populations. Inter-population comparison of hematological parameters [Hb F (p < 0.001), Hb A2 (p < 0.001), Hb (p = 0.03) and red blood cell distribution width (RDW) (p < 0.001)] revealed significant differences. We also observed that mean Hb F levels were significantly higher in Hb S compared to Hb S-β-thal patients in the respective populations. Our study highlights the higher prevalence of β-thal as well as the compound heterozygosity for Hb S and β-thal in various populations of Chhattisgarh State, India.
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Affiliation(s)
- Aditya N Jha
- a Sickle Cell Institute Chhattisgarh (SCIC), Pandit Jawaharlal Nehru Memorial Medical College Campus , Raipur , Chhattisgarh State , India
| | - Hrishikesh Mishra
- a Sickle Cell Institute Chhattisgarh (SCIC), Pandit Jawaharlal Nehru Memorial Medical College Campus , Raipur , Chhattisgarh State , India
| | - Henu K Verma
- a Sickle Cell Institute Chhattisgarh (SCIC), Pandit Jawaharlal Nehru Memorial Medical College Campus , Raipur , Chhattisgarh State , India
| | - Isha Pandey
- a Sickle Cell Institute Chhattisgarh (SCIC), Pandit Jawaharlal Nehru Memorial Medical College Campus , Raipur , Chhattisgarh State , India
| | - Bhaskar V K S Lakkakula
- a Sickle Cell Institute Chhattisgarh (SCIC), Pandit Jawaharlal Nehru Memorial Medical College Campus , Raipur , Chhattisgarh State , India
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16
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Soukup D, Kuechler A, Roesler J, Pichlmaier L, Eckerland M, Olivier M, Stehling F. Genetic Diagnostic Elucidation of a Patient With Multiorgan Granulomas, Facial Peculiarities, and Psychomotor Retardation. Front Genet 2018; 9:355. [PMID: 30319683 PMCID: PMC6170790 DOI: 10.3389/fgene.2018.00355] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 08/20/2018] [Indexed: 11/13/2022] Open
Abstract
We report the case of a 19-years-old patient who presented with a perplexing variety of symptoms which included remarkable facial features, intellectual disability, granulomatous upper lip swelling (previously diagnosed as Melkersson-Rosenthal syndrome), Crohn's-like disease, non-productive cough, and a granulomatous mass localized in the left lung. Chronic granulomatous disease (CGD) was diagnosed using dihydrorhodamine 123 assay that showed low levels of phagocytic NADPH-oxidase. DNA sequencing revealed a heterozygous mutation in the NCF-1 gene on chromosome 7. As remarkable facial features and psychomotor retardation are not associated with CGD, a more detailed genetic work-up using fluorescence in situ hybridization was performed. A microdeletion in 7q11.23 on one allele indicated Williams-Beuren syndrome (WBS). The NCF-1 gene and its two pseudogenes are part of a highly repetitive region within 7q11.23 and are prone to recombination events and deletions. Such deletions can involve both the WBS critical region and the NCF-1 wildtype gene, as was the case for our patient. The second allele of the NCF-1 gene was affected by the frequent c.75.76delGT mutation that stems from a recombination of the NCF-1 wildtype gene with one of its pseudogenes. In conclusion, patients with NCF-1-deficient CGD may also harbor microdeletions that result in WBS or other hereditary disorders; therefore, it is important to perform a thorough genetic analysis in order to initiate appropriate therapy for these patients.
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Affiliation(s)
- Daniel Soukup
- Klinik für Kinderheilkunde I, Universitätsklinikum Essen, Essen, Germany
| | - Alma Kuechler
- Institut für Humangenetik, Universitätsklinikum Essen, Essen, Germany
| | - Joachim Roesler
- Klinik und Poliklinik für Kinder- und Jugendmedizin, Universitätsklinikum Carl Gustav Carus, Dresden, Germany
| | - Leopold Pichlmaier
- Klinik für Kinderheilkunde III, Universitätsklinikum Essen, Essen, Germany
| | | | - Margarete Olivier
- Klinik für Kinderheilkunde III, Universitätsklinikum Essen, Essen, Germany
| | - Florian Stehling
- Klinik für Kinderheilkunde III, Universitätsklinikum Essen, Essen, Germany
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17
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Stevenson RE, Vincent V, Spellicy CJ, Friez MJ, Chaubey A. Biallelic deletions of the Waardenburg II syndrome gene, SOX10, cause a recognizable arthrogryposis syndrome. Am J Med Genet A 2018; 176:1968-1971. [PMID: 30113773 DOI: 10.1002/ajmg.a.40362] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 05/09/2018] [Accepted: 05/21/2018] [Indexed: 11/11/2022]
Abstract
Random mating in the general population tends to limit the occurrence of homozygous and compound heterozygous forms of dominant hereditary disorders. Certain phenotypes, the most recognized being skeletal dysplasias associated with short stature, lead to cultural interaction and assortative mating. To this well-known example, may be added deafness which brings together individuals with a variety of deafness genotypes, some being dominant. Waardenburg syndrome is one such autosomal dominant disorder in which affected individuals may interact culturally because of deafness. Biallelic genetic alterations for two Waardenburg genes, PAX3 and MITF have been previously recognized. Herein, we report biallelic deletions in SOX10, a gene associated with Waardenburg syndromes type II and IV. The affected fetuses have a severe phenotype with a lack of fetal movement resulting in four-limb arthrogryposis and absence of palmar and plantar creases, white hair, dystopia canthorum, and in one case cleft palate and in the other a cardiac malformation.
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Affiliation(s)
| | - Victoria Vincent
- University of South Carolina School of Medicine, Columbia, South Carolina
| | | | | | - Alka Chaubey
- Greenwood Genetic Center, Greenwood, South Carolina
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18
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Zhou F, Mao J, Ye Q, Zhu X, Zhang Y, Ye Y, Fu H, Shen H, Lu Z, Xia Y, Liu A, Shu Q, Du L. Clinical features and genetic findings in Chinese children with distal renal tubular acidosis. Int J Clin Exp Pathol 2018; 11:3523-3532. [PMID: 31949730 PMCID: PMC6962865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 04/28/2018] [Indexed: 06/10/2023]
Abstract
Distal renal tubular acidosis (dRTA) is characterized by metabolic acidosis due to uric acid dysfunction. The aim of this study was to demonstrate the genetic diagnosis of Chinese children with dRTA by whole-exome sequencing. From Jan. 2010 to Sept. 2015, 16 children with dRTA were recruited to investigate the possibility of genetic diagnosis and to examine any genotype-phenotype relationships in these patients. Sanger sequencing was used to confirm mutations identified by whole-exome sequencing. Clinical and biological features in the patients included hyperchloremic metabolic acidosis, impaired growth, hypokalemia, nephrocalcinosis, nephrolithiasis, hypercalciuria, hypocitraturia, and rickets or osteomalacia. Seventeen mutations in the solute carrier family 4 member 1 (SLC4A1), ATPase H+ transporting V0 subunit a4 (ATP6V0A4), ATPase H+ transporting V1 subunit B1 (ATP6V1B1), WNK lysine deficient protein kinase 1 (WNK1) and the claudin 16 (CLDN16) were identified in 15 patients, and 14 of these mutations are novel. Only 1 patient was negative for any mutations. Our results demonstrate the existence of SLC4A1, ATP6V1B1, ATP6V0A4, WNK1 and CLDN16 mutations in Chinese children with dRTA and indicate that compound heterozygosity at 2 or more different but related genes can be responsible for its pathogenesis. This study also indicates that whole-exome sequencing is a labor and cost-effective means of analyzing dRTA-associated genes.
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Affiliation(s)
- Fang Zhou
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
- Department of Internal Medicine, Hangzhou Children’s HospitalHangzhou, Zhejiang Province, China
| | - Jianhua Mao
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Qing Ye
- Department of Zhejiang Key Laboratory for Neonatal Diseases, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Xiujuan Zhu
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Yingying Zhang
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Yuhong Ye
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Haidong Fu
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Huijun Shen
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Zhihong Lu
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Yonghui Xia
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Aimin Liu
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Qiang Shu
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
| | - Lizhong Du
- Department of Nephrology, The Children’s Hospital of Zhejiang University School of MedicineHangzhou, Zhejiang Province, China
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19
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Jiang T, Huang M, Jiang T, Gu Y, Wang Y, Wu Y, Ma H, Jin G, Dai J, Hu Z. Genome-wide compound heterozygosity analysis highlighted 4 novel susceptibility loci for congenital heart disease in Chinese population. Clin Genet 2018; 94:296-302. [PMID: 29774522 DOI: 10.1111/cge.13384] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 04/25/2018] [Accepted: 05/15/2018] [Indexed: 01/25/2023]
Abstract
Genome-wide association studies (GWASs) have achieved great success in deciphering the genetic cause of congenital heart disease (CHD). However, the heritability of CHD remains to be clarified, and numerous genetic factors responsible for occurrence of CHD are yet unclear. In this study, we performed a genome-wide search for relaxed forms of compound heterozygosity (CH) in association with CHD using our existing GWAS data including 2265 individuals (957 CHD cases and 1308 controls). CollapsABEL was used to iteratively test the association between the CH genotype and the CHD phenotype in a sliding window manner. We highlighted 17 genetic loci showing suggestive CH-like associations with CHD (P < 5 × 10-8 ), among which 4 genetic loci had expression quantitative trait loci (eQTL) effects in blood (PeQTL < 0.01). After conditional association analysis, each loci had only 1 independently effective signal reaching the significance threshold (rs2071477/rs3129299 at 6p21.32, P = 2.47 × 10-10 ; rs10773097/rs2880921 at 12q24.31, P = 3.30 × 10-8 ; rs73032040/rs7259476 at 19q13.11, P = 1.14 × 10-8 ; rs10416386/rs4239517 at 19q13.31, P = 1.15 × 10-9 ), together explained 7.83% of the CHD variance. Among these 4 associated loci, outstanding candidates for CHD-associated genes included UBC, CFM2, ZNF302, LYPD3 and CADM4. Although replication studies with larger sample size are warranted, the first CH GWAS of CHD may extend our current knowledge of the genetic contributions to CHD in the Han Chinese population.
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Affiliation(s)
- T Jiang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China.,Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, China
| | - M Huang
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, China
| | - T Jiang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China.,Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Y Gu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China.,Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Y Wang
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China.,Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Y Wu
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, China
| | - H Ma
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, China
| | - G Jin
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China.,Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, China
| | - J Dai
- Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, China
| | - Z Hu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China.,Department of Epidemiology and Biostatistics, School of Public Health, Nanjing Medical University, Nanjing, China
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20
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Peplonska B, Berdynski M, Mandecka M, Barczak A, Kuzma-Kozakiewicz M, Barcikowska M, Zekanowski C. TREM2 variants in neurodegenerative disorders in the Polish population. Homozygosity and compound heterozygosity in FTD patients. Amyotroph Lateral Scler Frontotemporal Degener 2018; 19:407-412. [PMID: 29557178 DOI: 10.1080/21678421.2018.1451894] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Activation of the TREM2 receptor on microglia stimulates phagocytosis and decreases the microglial proinflammatory response. Mutations in exon 2 of the TREM2 gene have been reported to be associated with various neurodegenerative diseases characterized by chronic inflammation. The aim of our study was to evaluate exon 2 of TREM2 gene variants as a putative genetic risk factor for Alzheimer's disease (AD), frontotemporal dementia (FTD), and amyotrophic lateral sclerosis (ALS) in the Polish population. The results were interpreted using previously published data, especially highlighting differences in the prevalence of the variants among Caucasian subpopulations across different geographic regions. The DNA sequence of exon 2 of TREM2 was analyzed in 811 subjects (274 AD, 135 FTD, 194 ALS patients, and 208 neurologically healthy controls). Nine heterozygous variants were detected, including two novel ones: p.G29 = and c.41-2_3insA, found respectively in a control and an ALS patient. Additionally, we identified one homozygous and two compound heterozygous FTD patients. We confirm previous data that homozygous and compound heterozygous TREM2 mutations can be causative for FTD.
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Affiliation(s)
- Beata Peplonska
- a Department of Neurodegenerative Disorders , Mossakowski Medical Research Centre Polish Academy of Sciences , Warsaw , Poland
| | - Mariusz Berdynski
- a Department of Neurodegenerative Disorders , Mossakowski Medical Research Centre Polish Academy of Sciences , Warsaw , Poland
| | - Monika Mandecka
- a Department of Neurodegenerative Disorders , Mossakowski Medical Research Centre Polish Academy of Sciences , Warsaw , Poland
| | - Anna Barczak
- a Department of Neurodegenerative Disorders , Mossakowski Medical Research Centre Polish Academy of Sciences , Warsaw , Poland
| | - Magdalena Kuzma-Kozakiewicz
- b Department of Neurology , and.,c Neurodegenerative Diseases Research Group Medical University of Warsaw , Warsaw , Poland
| | - Maria Barcikowska
- a Department of Neurodegenerative Disorders , Mossakowski Medical Research Centre Polish Academy of Sciences , Warsaw , Poland
| | - Cezary Zekanowski
- a Department of Neurodegenerative Disorders , Mossakowski Medical Research Centre Polish Academy of Sciences , Warsaw , Poland
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21
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Duijkers L, van den Born LI, Neidhardt J, Bax NM, Pierrache LHM, Klevering BJ, Collin RWJ, Garanto A. Antisense Oligonucleotide-Based Splicing Correction in Individuals with Leber Congenital Amaurosis due to Compound Heterozygosity for the c.2991+1655A>G Mutation in CEP290. Int J Mol Sci 2018; 19:E753. [PMID: 29518907 DOI: 10.3390/ijms19030753] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Leber congenital amaurosis (LCA) is a rare inherited retinal disorder affecting approximately 1:50,000 people worldwide. So far, mutations in 25 genes have been associated with LCA, with CEP290 (encoding the Centrosomal protein of 290 kDa) being the most frequently mutated gene. The most recurrent LCA-causing CEP290 mutation, c.2991+1655A>G, causes the insertion of a pseudoexon into a variable proportion of CEP290 transcripts. We previously demonstrated that antisense oligonucleotides (AONs) have a high therapeutic potential for patients homozygously harbouring this mutation, although to date, it is unclear whether rescuing one single allele is enough to restore CEP290 function. Here, we assessed the AON efficacy at RNA, protein and cellular levels in samples that are compound heterozygous for this mutation, together with a protein-truncating mutation in CEP290. We demonstrate that AONs can efficiently restore splicing and increase protein levels. However, due to a high variability in ciliation among the patient-derived cell lines, the efficacy of the AONs was more difficult to assess at the cellular level. This observation points towards the importance of the severity of the second allele and possibly other genetic variants present in each individual. Overall, AONs seem to be a promising tool to treat CEP290-associated LCA, not only in homozygous but also in compound heterozygous carriers of the c.2991+1655A>G variant.
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22
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Banerjee S, Chen H, Huang H, Wu J, Yang Z, Deng W, Chen D, Deng J, Su Y, Li Y, Wu C, Wang Y, Zeng H, Wang Y, Li X. Novel mutations c.28G>T (p.Ala10Ser) and c.189G>T (p.Glu63Asp) in WDR62 associated with early onset acanthosis and hyperkeratosis in a patient with autosomal recessive microcephaly type 2. Oncotarget 2018; 7:78363-78371. [PMID: 27852057 PMCID: PMC5346645 DOI: 10.18632/oncotarget.13279] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Accepted: 11/01/2016] [Indexed: 11/28/2022] Open
Abstract
Microcephaly (MCPH) is a developmental disorder characterized by reduced brain size and intellectual disability. A proportion of microcephaly is caused by defects in a single gene. Microcephaly 2 (MCPH2) is one of the most frequent subtypes of MCPH.WD repeat-containing protein 62 gene (WDR62) is the most frequently mutated gene in MCPH2 patients. Phenotypes involving dermatological changes in MCPH2 have not been reported. We have identified and investigated a 5-year-old Chinese girl with markedly reduced brain size (86% of normal size), intellectual disability and psychomotor developmental delay. The patient also exhibited spattered blisters and reduced hair density on her head, anisochromasia with reticular hyperpigmentation and hypopigmentation on the trunk, which she has had since the age of 4 and had been found by her parents. Histological examination of a skin biopsy revealed acanthosis, hyperkeratosis and necrotic keratinocytes. Whole exome and Sanger sequencing identified two novel missense mutations, c.28G>T and c.189G>T, in the WDR62 gene. Both the mutations non-synonymously affect evolutionarily conserved amino acids and are predicted to be disease causing. We report the first case of MCPH2 that also presented with marked dermatological changes. Our findings expand the mutational and phenotypical spectra of MCPH2 and are valuable in the mutation-based pre- and post-natal screening and genetic diagnosis for MCPH2.
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Affiliation(s)
| | | | | | - Jing Wu
- BGI-Shenzhen, Shenzhen, China
| | - Zhiyun Yang
- Department of Medical Imaging, 1st affiliated hospital, Sun Yat-sen University, Guangzhou, PR China
| | - Weiping Deng
- Department of Dermatology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, PR China
| | | | | | - Yan Su
- BGI-Shenzhen, Shenzhen, China
| | - Yang Li
- BGI-Shenzhen, Shenzhen, China
| | - Chao Wu
- Department of Neurology, 1st affiliated hospital, Sun Yat-sen University, Guangzhou, PR China
| | - Ye Wang
- Department of Medical Genetics, Center for Genome Research, Sun Yat-sen University, Guangzhou, PR China
| | - Hao Zeng
- Department of Medical Genetics, Center for Genome Research, Sun Yat-sen University, Guangzhou, PR China
| | - Yiming Wang
- Xinhua College, Sun Yat-sen university, Guangzhou, PR China.,BGI-Shenzhen, Shenzhen, China
| | - Xunhua Li
- Department of Neurology, 1st affiliated hospital, Sun Yat-sen University, Guangzhou, PR China
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23
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Lun Y, Sun X, Wang P, Chi J, Hou X, Wang Y. Severe hypertriglyceridemia due to two novel loss-of-function lipoprotein lipase gene mutations (C310R/E396V) in a Chinese family associated with recurrent acute pancreatitis. Oncotarget 2017; 8:47741-47754. [PMID: 28548960 PMCID: PMC5564601 DOI: 10.18632/oncotarget.17762] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 04/11/2017] [Indexed: 11/25/2022] Open
Abstract
Lipoprotein lipase (LPL) is widely expressed in skeletal muscles, cardiac muscles as well as adipose tissue and involved in the catabolism of triglyceride. Herein we have systematically characterized two novel loss-of-function mutations in LPL from a Chinese family in which afflicted members were manifested by severe hypertriglyceridemia and recurrent pancreatitis. DNA sequencing revealed that the proband was a heterozygote carrying a novel c.T928C (p.C310R) mutation in exon 6 of the LPL gene. Another member of the family was detected to be a compound heterozygote who along with the c.T928C mutation also carried a novel missense mutation c.A1187T (p.E396V) in exon 8 of the LPL gene. Furthermore, COS-1 cells were transfected with lentiviruses containing the mutant LPL genes. While C310R markedly reduced the overall LPL protein level, COS-1 cells carrying E396V or double mutations contained similar overall LPL protein levels to the wild-type. The specific activity of the LPL mutants remained at comparable magnitude to the wild-type. However, few LPL were detected in the culture medium for the mutants, suggesting that both mutations caused aberrant triglyceride catabolism. More specifically, E396V and double mutations dampened the transport of LPL to the cell surface, while for the C310R mutation, reducing LPL protein level might be involved. By characterizing these two novel LPL mutations, this study has expanded our understanding on the pathogenesis of familial hypertriglyceridemia (FHTG).
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Affiliation(s)
- Yu Lun
- Department of Endocrinology and Metabolic Diseases, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Xiaofang Sun
- Department of Endocrinology and Metabolic Diseases, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Ping Wang
- Department of Endocrinology and Metabolic Diseases, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Jingwei Chi
- Department of Endocrinology and Metabolic Diseases, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Xu Hou
- Department of Endocrinology and Metabolic Diseases, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yangang Wang
- Department of Endocrinology and Metabolic Diseases, The Affiliated Hospital of Qingdao University, Qingdao, China
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Takeda K, Kou I, Kawakami N, Iida A, Nakajima M, Ogura Y, Imagawa E, Miyake N, Matsumoto N, Yasuhiko Y, Sudo H, Kotani T, Nakamura M, Matsumoto M, Watanabe K, Ikegawa S. Compound Heterozygosity for Null Mutations and a Common Hypomorphic Risk Haplotype in TBX6 Causes Congenital Scoliosis. Hum Mutat 2017; 38:317-323. [PMID: 28054739 DOI: 10.1002/humu.23168] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 12/26/2016] [Indexed: 12/17/2022]
Abstract
Congenital scoliosis (CS) occurs as a result of vertebral malformations and has an incidence of 0.5-1/1,000 births. Recently, TBX6 on chromosome 16p11.2 was reported as a disease gene for CS; about 10% of Chinese CS patients were compound heterozygotes for rare null mutations and a common haplotype defined by three SNPs in TBX6. All patients had hemivertebrae. We recruited 94 Japanese CS patients, investigated the TBX6 locus for both mutations and the risk haplotype, examined transcriptional activities of mutant TBX6 in vitro, and evaluated clinical and radiographic features. We identified TBX6 null mutations in nine patients, including a missense mutation that had a loss of function in vitro. All had the risk haplotype in the opposite allele. One of the mutations showed dominant negative effect. Although all Chinese patients had one or more hemivertebrae, two Japanese patients did not have hemivertebra. The compound heterozygosity of null mutations and the common risk haplotype in TBX6 also causes CS in Japanese patients with similar incidence. Hemivertebra was not a specific type of spinal malformation in TBX6-associated CS (TACS). A heterozygous TBX6 loss-of-function mutation has been reported in a family with autosomal-dominant spondylocostal dysostosis, but it may represent a spectrum of the same disease with TACS.
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Affiliation(s)
- Kazuki Takeda
- Laboratory of Bone and Joint Diseases, Center for Integrative Medical Sciences, RIKEN, Tokyo, 160-8582, Japan.,Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, 108-8639, Japan
| | - Ikuyo Kou
- Laboratory of Bone and Joint Diseases, Center for Integrative Medical Sciences, RIKEN, Tokyo, 160-8582, Japan
| | - Noriaki Kawakami
- Department of Orthopaedic Surgery, Meijo Hospital, Nagoya, 460-0001, Japan
| | - Aritoshi Iida
- Laboratory of Bone and Joint Diseases, Center for Integrative Medical Sciences, RIKEN, Tokyo, 160-8582, Japan
| | - Masahiro Nakajima
- Laboratory of Bone and Joint Diseases, Center for Integrative Medical Sciences, RIKEN, Tokyo, 160-8582, Japan
| | - Yoji Ogura
- Laboratory of Bone and Joint Diseases, Center for Integrative Medical Sciences, RIKEN, Tokyo, 160-8582, Japan.,Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, 108-8639, Japan
| | - Eri Imagawa
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Noriko Miyake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, 236-0004, Japan
| | - Yukuto Yasuhiko
- Division of Cellular and Molecular Toxicology, National Institute of Health Sciences, Tokyo, 158-8501, Japan
| | - Hideki Sudo
- Department of Advanced Medicine for Spine and Spinal Cord Disorders, Hokkaido University Graduate School of Medicine, Sapporo, 060-8648, Japan
| | - Toshiaki Kotani
- Department of Orthopaedic Surgery, Seirei Sakura Citizen Hospital, Sakura, 285-0825, Japan
| | | | - Masaya Nakamura
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, 108-8639, Japan
| | - Morio Matsumoto
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, 108-8639, Japan
| | - Kota Watanabe
- Department of Orthopaedic Surgery, Keio University School of Medicine, Tokyo, 108-8639, Japan
| | - Shiro Ikegawa
- Laboratory of Bone and Joint Diseases, Center for Integrative Medical Sciences, RIKEN, Tokyo, 160-8582, Japan
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Abstract
β-Thalassemia (β-thal) is a common hereditary anemia due to decreased or absent synthesis of the β-globin chains. Here, we report a patient found to be a novel compound heterozygote for the rare IVS-II-5 (G > C) (NG_000007.3: g.71044G > C) and IVS-II-672 (A > C) (NG_000007.3: g.71711A > C) mutations, which may be silent mutations that are associated with consistent residual output of β chains, normal red blood cell (RBC) indices and normal or borderline Hb A2 levels.
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Affiliation(s)
- Lin Zhao
- a Department of Laboratory , The People's Hospital of Guangxi Zhuang Autonomous Region , Nanning , People's Republic of China
| | - Jilin Qing
- b Department of Gynecology , The People's Hospital of Guangxi Zhuang Autonomous Region , Nanning , People's Republic of China
| | - Yue Liang
- a Department of Laboratory , The People's Hospital of Guangxi Zhuang Autonomous Region , Nanning , People's Republic of China
| | - Zhizhong Chen
- a Department of Laboratory , The People's Hospital of Guangxi Zhuang Autonomous Region , Nanning , People's Republic of China
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Cheng LL, Han RY, Yang FY, Yu XP, Xu JL, Min QJ, Tian J, Ge XL, Zheng SS, Lin YW, Zheng YH, Qu J, Gu F. Novel mutations in PDE6B causing human retinitis pigmentosa. Int J Ophthalmol 2016; 9:1094-9. [PMID: 27588261 DOI: 10.18240/ijo.2016.08.02] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 02/14/2016] [Indexed: 11/23/2022] Open
Abstract
AIM To identify the genetic defects of a Chinese patient with sporadic retinitis pigmentosa (RP). METHODS Ophthalmologic examinations were performed on the sporadic RP patient, 144 genes associated with retinal diseases were scanned with capture next generation sequencing (CNGS) approach. Two heterozygous mutations in PDE6B were confirmed in the pedigree by Sanger sequencing subsequently. The carrier frequency of PDE6B mutations of reported PDE6B mutations based on the available two public exome databases (1000 Genomes Project and ESP6500 Genomes Project) and one in-house exome database was investigated. RESULTS We identified compound heterozygosity of two novel nonsense mutations c.1133G>A (p.W378X) and c.2395C>T (p.R799X) in PDE6B, one reported causative gene for RP. Neither of the two mutations in our study was presented in three exome databases. Two mutations (p.R74C and p.T604I) in PDE6B have relatively high frequencies in the ESP6500 and in-house databases, respectively, while no common dominant mutation in each of the database or across all databases. CONCLUSION We demonstrates that compound heterozygosity of two novel nonsense mutations in PDE6B could lead to RP. These results collectively point to enormous potential of next-generation sequencing in determining the genetic etiology of RP and how various mutations in PDE6B contribute to the genetic heterogeneity of RP.
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Affiliation(s)
- Lu-Lu Cheng
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Ru-Yi Han
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Fa-Yu Yang
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Xin-Ping Yu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Jin-Ling Xu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Qing-Jie Min
- Institute of Genomic Medicine, Wenzhou Medical University, Wenzhou 325027, Zhejiang Province, China
| | - Jie Tian
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Xiang-Lian Ge
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Si-Si Zheng
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Ye-Wen Lin
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Yi-Han Zheng
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Jia Qu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Feng Gu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
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Wang L, Yang Y, Song J, Mao L, Wei X, Sun Y, Yang S, Mu F, Wang H, Niu Y. Two novel mutations in the C-terminal region of centrosomal protein 290 (CEP290) result in classic Joubert syndrome. J Child Neurol 2015; 30:772-6. [PMID: 24850569 DOI: 10.1177/0883073814535488] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2013] [Accepted: 04/17/2014] [Indexed: 01/04/2023]
Abstract
Joubert syndrome is a neurologic disorder with a pathognomonic "molar tooth sign" on brain imaging. The purpose of this study was to identify potential mutations in a Chinese patient with Joubert syndrome by targeted massively parallel sequencing. Taking advantage of high-throughput DNA sequencing technologies, 18 Joubert-causing genes of a Chinese patient with classic Joubert syndrome were sequenced at a time, and 2 novel variants in the CEP290 gene (c.7323_7327delAGAAG and c.6012-2A>G) were identified in this patient. Sanger validation showed that 2 variants were inherited from each parents, respectively. Both variants are located in the C-terminal region of the CEP290 protein and are predicted to be deleterious. The results support that the combination of targeted genes enrichment and next-generation sequencing is valuable molecular diagnostic tool and suitable for clinical application.
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Affiliation(s)
- Lixia Wang
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | | | - Jieping Song
- Prenatal Diagnosis Center, Hubei Maternal and Child Health Hospital, China
| | | | | | - Yan Sun
- BGI-Shenzhen, Shenzhen, China
| | | | | | | | - Yanfeng Niu
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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28
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Krupp DR, Soldano KL, Garrett ME, Cope H, Ashley-Koch AE, Gregory SG. Missing genetic risk in neural tube defects: can exome sequencing yield an insight? ACTA ACUST UNITED AC 2014; 100:642-6. [PMID: 25044326 DOI: 10.1002/bdra.23276] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 05/30/2014] [Accepted: 05/31/2014] [Indexed: 01/12/2023]
Abstract
BACKGROUND Neural tube defects (NTD) have a strong genetic component, with up to 70% of variance in human prevalence determined by heritable factors. Although the identification of causal DNA variants by sequencing candidate genes from functionally relevant pathways and model organisms has provided some success, alternative approaches are demanded. METHODS Next generation sequencing platforms are facilitating the production of massive amounts of sequencing data, primarily from the protein coding regions of the genome, at a faster rate and cheaper cost than has previously been possible. These platforms are permitting the identification of variants (de novo, rare, and common) that are drivers of NYTD etiology, and the cost of the approach allows for the screening of increased numbers of affected and unaffected individuals from NTD families and in simplex cases. CONCLUSION The next generation sequencing platforms represent a powerful tool in the armory of the genetics researcher to identify the causal genetic basis of NTDs.
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Affiliation(s)
- Deidre R Krupp
- Duke Molecular Physiology Institute, DUMC, 300 North Duke Street, Durham, NC, 27701
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29
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Cradic KW, Murphy SJ, Drucker TM, Sikkink RA, Eberhardt NL, Neuhauser C, Vasmatzis G, Grebe SKG. A simple method for gene phasing using mate pair sequencing. BMC Med Genet 2014; 15:19. [PMID: 24502676 PMCID: PMC3930533 DOI: 10.1186/1471-2350-15-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 01/20/2014] [Indexed: 12/27/2022]
Abstract
BACKGROUND Recessive genes cause disease when both copies are affected by mutant loci. Resolving the cis/trans relationship of variations has been an important problem both for researchers, and increasingly, clinicians. Of particular concern are patients who have two heterozygous disease-causing mutations and could be diagnosed as affected (one mutation on each allele) or as phenotypically normal (both mutations on the same allele). Several methods are currently used to phase genes, however due to cost, complexity and/or low sensitivity they are not suitable for clinical purposes. METHODS Long-range amplification was used to select and enrich the target gene (CYP21A2) followed by modified mate-pair sequencing. Fragments that mapped coincidently to two heterozygous sites were identified and used for statistical analysis. RESULTS Probabilities for cis/trans relationships between heterozygous positions were calculated along with 99% confidence intervals over the entire length of our 10 kb amplicons. The quality of phasing was closely related to the depth of coverage and the number of erroneous reads. Most of the error was found to have been introduced by recombination in the PCR reaction. CONCLUSIONS We have developed a simple method utilizing massively parallel sequencing that is capable of resolving two alleles containing multiple heterozygous positions. This method stands out among other phasing tools because it provides quantitative results allowing confident haplotype calls.
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Affiliation(s)
- Kendall W Cradic
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA
| | - Stephen J Murphy
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | | | - Robert A Sikkink
- Adavanced Genomics Technology Center, Mayo Clinic, Rochester, MN 55905, USA
| | - Norman L Eberhardt
- Department of Medicine, Division of Endocrinology, Mayo Clinic, Rochester, MN 55905, USA
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
| | - Claudia Neuhauser
- Biomedical Informatics and Computational Biology, University of Minnesota Rochester, 111 South Broadway, Suite 300, Rochester, MN 55904, USA
| | - George Vasmatzis
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Stefan KG Grebe
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA
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Ricchi P, Ammirabile M, Spasiano A, Costantini S, Di Matola T, Pepe A, Cinque P, Pagano L, Casale M, Filosa A, Prossomariti L. Extramedullary haematopoiesis correlates with genotype and absence of cardiac iron overload in polytransfused adults with thalassaemia. Blood Transfus 2014; 12 Suppl 1:s124-30. [PMID: 24120603 PMCID: PMC3934250 DOI: 10.2450/2013.0287-12] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 05/20/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND The mechanisms responsible for the sporadic occurrence of extramedullary haematopoiesis in polytransfused thalassaemic patients have not yet been clarified. In this study we tried to elucidate the influence of genotype and other factors on the presence of extramedullary haematopoiesis. MATERIALS AND METHODS We performed a retrospective database review of our polytransfused thalassaemic patients between January 2006 and December 2011. Demographic, transfusional, genetic, radiological and biochemical data were collected and statistically analysed. RESULTS Extramedullary haematopoiesis was found in 18 out of 67 patients (27%). All of them were splenectomised, had a higher nucleated red blood cell count and higher levels of the soluble form of transferrin receptor with respect to patients without extramedullary haematopoiesis; furthermore, patients with EMH had a lower transfusional iron intake and a higher pre-transfusion haemoglobin level as compared with those without extramedullary haematopoiesis. Ten out of the 18 patients with extramedullary haematopoiesis were compound heterozygotes for IVS 1-6/codon 39. A high frequency of thrombotic events was also recorded among all patients followed at our centre with this genetic profile. DISCUSSION Among our cohort of thalassaemic polytransfused patients, extramedullary haematopoiesis was not such a rare event. Furthermore, we identified a group of patients, most of whom were compound heterozygotes for IVS 1-6/codon 39, with increased soluble transferrin receptor levels and excessive expansion of erythroid marrow probably responsible for the tendency to develop extramedullary haematopoiesis.
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Affiliation(s)
- Paolo Ricchi
- Department of Oncohaematology, U.O.S.D. “A. Mastrobuoni” Microcythaemia Centre, “A. Cardarelli” Hospital (AORN), Naples, Italy
| | - Massimiliano Ammirabile
- Department of Oncohaematology, U.O.S.D. “A. Mastrobuoni” Microcythaemia Centre, “A. Cardarelli” Hospital (AORN), Naples, Italy
| | - Anna Spasiano
- Department of Oncohaematology, U.O.S.D. “A. Mastrobuoni” Microcythaemia Centre, “A. Cardarelli” Hospital (AORN), Naples, Italy
| | - Silvia Costantini
- Department of Oncohaematology, U.O.S.D. “A. Mastrobuoni” Microcythaemia Centre, “A. Cardarelli” Hospital (AORN), Naples, Italy
| | - Tiziana Di Matola
- Department of Diagnostic Services, U.O.C., Biochemical Clinic, A.O.R.N. dei Colli Hospital, Naples, Italy
| | - Alessia Pepe
- Magnetic Resonance Imaging Unit, Fondazione G. Monasterio, CNR-Regione Toscana, Pisa, Italy
| | - Patrizia Cinque
- Department of Oncohaematology, U.O.S.D. “A. Mastrobuoni” Microcythaemia Centre, “A. Cardarelli” Hospital (AORN), Naples, Italy
| | - Leonilde Pagano
- Department of Oncohaematology, U.O.S.D. “A. Mastrobuoni” Microcythaemia Centre, “A. Cardarelli” Hospital (AORN), Naples, Italy
| | - Maddalena Casale
- Department of Oncohaematology, U.O.S.D. “A. Mastrobuoni” Microcythaemia Centre, “A. Cardarelli” Hospital (AORN), Naples, Italy
| | - Aldo Filosa
- Department of Oncohaematology, U.O.S.D. “A. Mastrobuoni” Microcythaemia Centre, “A. Cardarelli” Hospital (AORN), Naples, Italy
| | - Luciano Prossomariti
- Department of Oncohaematology, U.O.S.D. “A. Mastrobuoni” Microcythaemia Centre, “A. Cardarelli” Hospital (AORN), Naples, Italy
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Mozzillo E, Melis D, Falco M, Fattorusso V, Taurisano R, Flanagan SE, Ellard S, Franzese A. Thiamine responsive megaloblastic anemia: a novel SLC19A2 compound heterozygous mutation in two siblings. Pediatr Diabetes 2013; 14:384-7. [PMID: 23289844 DOI: 10.1111/j.1399-5448.2012.00921.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 07/12/2012] [Accepted: 08/02/2012] [Indexed: 01/19/2023] Open
Abstract
Thiamine responsive megaloblastic anemia (TRMA) is an autosomal recessive disease caused by loss of function mutations in the SLC19A2 gene. TRMA is characterized by anemia, deafness, and diabetes. In some cases, optic atrophy or more rarely retinitis pigmentosa is noted. We now report two sisters, the eldest of which presented to a different hospital during childhood with sensorineural deafness, which was treated with a hearing prosthesis, insulin requiring diabetes, retinitis pigmentosa, optic atrophy, and macrocytic anemia. These features initially suggested a clinical diagnosis of Wolfram syndrome (WS). Therapy with thiamine was initiated which resulted in the resolution of the anemia. The younger sister, who was affected with sensorineural deafness, was referred to our hospital for non-autoimmune diabetes. She was found to have macrocytosis and ocular abnormalities. Because a diagnosis of TRMA was suspected, therapy with insulin and thiamine was started. Sequencing analysis of the SLC19A2 gene identified a compound heterozygous mutation p.Y81X/p.L457X (c.242insA/c.1370delT) in both sisters. Non-autoimmune diabetes associated with deafness and macrocytosis, without anemia, suggests a diagnosis of TRMA. Patients clinically diagnosed with WS with anemia and/or macrocytosis should be reevaluated for TRMA.
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Affiliation(s)
- Enza Mozzillo
- Department of Pediatrics, Federico II University of Naples, Naples, Italy.
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Vorstman JA, van Daalen E, Jalali GR, Schmidt ER, Pasterkamp RJ, de Jonge M, Hennekam EA, Janson E, Staal WG, van der Zwaag B, Burbach JP, Kahn RS, Emanuel BS, van Engeland H, Ophoff RA. A double hit implicates DIAPH3 as an autism risk gene. Mol Psychiatry 2011; 16:442-51. [PMID: 20308993 DOI: 10.1038/mp.2010.26] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Recent studies have shown that more than 10% of autism cases are caused by de novo structural genomic rearrangements. Given that some heritable copy number variants (CNVs) have been observed in patients as well as in healthy controls, to date little attention has been paid to the potential function of these non-de novo CNVs in causing autism. A normally intelligent patient with autism, with non-affected parents, was identified with a maternally inherited 10 Mb deletion at 13q21.2. Sequencing of the genes within the deletion identified a paternally inherited nonsynonymous amino-acid substitution at position 614 of diaphanous homolog 3 (DIAPH3) (proline to threonine; Pro614Thr). This variant, present in a highly conserved domain, was not found in 328 healthy subjects. Experiments showed a transient expression of Diaph3 in the developing murine cerebral cortex, indicating it has a function in brain development. Transfection of Pro614Thr in murine fibroblasts showed a significant reduction in the number of induced filopodia in comparison to the wild-type gene. DIAPH3 is involved in cell migration, axon guidance and neuritogenesis, and is suggested to function downstream of SHANK3. Our findings strongly suggest DIAPH3 as a novel autism susceptibility gene. Moreover, this report of a 'double-hit' compound heterozygote for a large, maternally inherited, genomic deletion and a paternally inherited rare missense mutation shows that not only de novo genomic variants in patients should be taken seriously in further study but that inherited CNVs may also provide valuable information.
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Abstract
The molecular approaches to distal renal tubular acidosis (dRTA) associated AE1 mutations lead us to understand the genetic and pathophysiological aspects of the acidification defects. An unanticipated high value of the urine-blood (U-B) PCO(2) after NaHCO(3) loading observed in a case of dRTA and southeast Asian ovalocytosis (SAO) might be from a mistarget of the AE1 to the luminal membrane of type A intercalated cells. The mutations of the AE1 gene resulted in SAO and also affected renal acidification function. Notwithstanding, after the NH4Cl loading in 20 individuals with SAO, the acidification in the distal nephron was normal. The presence of both SAO and G701D mutations of AE1 gene would explain the abnormal urinary acidification in the patients with the compound heterozogosity. In terms of the effect of the mutations on trafficking of AE1, truncated kidney isoform (kAE1) of wild-type showed a 'dominant-positive effect' in rescuing the recessive mutant kAE1 (S773P or G701D) trafficking to the plasma membrane, in contrast with the dominant mutant kAE1 (R589H) resulting in a 'dominant-negative effect' when heterodimerized with the wild-type kAE1. It is notable that the dominant mutants kAE1 (R901X or G609R) expression in MDCK cells clearly results in aberrant surface expression with some mutant protein appearing at the apical membrane. These might result in net bicarbonate secretion and increasing U-B PCO(2) in the distal nephron. The molecular physiological and genetic approaches have permitted identification of the molecular defects, predominantly in transporter proteins, and should in turn prompt development of novel therapeutic strategies.
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Affiliation(s)
- Somkiat Vasuvattakul
- Renal Division, Department of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
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34
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ten Kate LP, Teeuw M, Henneman L, Cornel MC. Autosomal recessive disease in children of consanguineous parents: inferences from the proportion of compound heterozygotes. J Community Genet 2010; 1:37-40. [PMID: 21475666 PMCID: PMC3063838 DOI: 10.1007/s12687-010-0002-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2009] [Accepted: 01/06/2010] [Indexed: 10/25/2022] Open
Abstract
This short communication deals with the questions of how to calculate the expected proportion of compound heterozygous patients among affected offspring of consanguineous parents, and how, from an observed proportion of compound heterozygotes, to calculate both the proportion of homozygotes not identical by descent and the frequency of pathogenic alleles in the population. This estimate of allele frequency may be useful when dealing with populations with a considerable number of consanguineous matings.
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Affiliation(s)
- Leo P. ten Kate
- Department of Clinical Genetics, Community Genetics Section, and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Marieke Teeuw
- Department of Clinical Genetics, Community Genetics Section, and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Lidewij Henneman
- Department of Clinical Genetics, Community Genetics Section, and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
| | - Martina C. Cornel
- Department of Clinical Genetics, Community Genetics Section, and EMGO Institute for Health and Care Research, VU University Medical Center, Amsterdam, The Netherlands
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