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Dib F, Quéméner A, Bayart S, Boisseau P, Babuty A, Trossaërt M, Sigaud M, Ternisien C, Drillaud N, Eveillard M, Guillet B, Béné MC, Fouassier M. Biological, clinical features and modelling of heterozygous variants of glycoprotein Ib platelet subunit alpha (GP1BA) and glycoprotein Ib platelet subunit beta (GP1BB) genes responsible for constitutional thrombocytopenia. Br J Haematol 2022; 199:744-753. [PMID: 36173017 DOI: 10.1111/bjh.18462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 08/29/2022] [Accepted: 08/31/2022] [Indexed: 11/28/2022]
Abstract
Constitutional thrombocytopenias are rare disorders, often difficult to discriminate from acquired thrombocytopenias. More than 80 genes have been described as being at the origin of these diseases. Among them, several variants of the glycoprotein Ib platelet subunit alpha (GP1BA) and glycoprotein Ib platelet subunit beta (GP1BB) genes, coding for the GpIb-IX-V glycoprotein complex, have been reported in the literature. The study reported here aimed at describing newly identified monoallelic anomalies affecting the GP1BA and GP1BB genes on a clinical, biological and molecular level. In a cohort of nine patients with macrothrombocytopenia, eight heterozygous variants of the GP1BA or GP1BB genes were identified. Five of them had never been described in the heterozygous state. Computer modelling disclosed structure/function relationships of these five variants.
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Affiliation(s)
- Fatema Dib
- Service d'Hématologie Biologique, CHU de Nantes, Nantes, France
| | - Agnès Quéméner
- Nantes Université, Inserm UMR 1307, CNRS UMR 6075, Université d'Angers, CRCI2NA, Nantes, France
| | | | - Pierre Boisseau
- Service de Génétique Médicale, CHU de Nantes, Nantes, France
| | - Antoine Babuty
- Service d'Hématologie Biologique, CHU de Nantes, Nantes, France.,CRC-MH, CHU de Nantes, Nantes, France
| | - Marc Trossaërt
- Service d'Hématologie Biologique, CHU de Nantes, Nantes, France.,CRC-MH, CHU de Nantes, Nantes, France
| | - Marianne Sigaud
- Service d'Hématologie Biologique, CHU de Nantes, Nantes, France.,CRC-MH, CHU de Nantes, Nantes, France
| | - Catherine Ternisien
- Service d'Hématologie Biologique, CHU de Nantes, Nantes, France.,CRC-MH, CHU de Nantes, Nantes, France
| | - Nicolas Drillaud
- Service d'Hématologie Biologique, CHU de Nantes, Nantes, France.,CRC-MH, CHU de Nantes, Nantes, France
| | - Marion Eveillard
- Service d'Hématologie Biologique, CHU de Nantes, Nantes, France.,Nantes Université, Inserm UMR 1307, CNRS UMR 6075, Université d'Angers, CRCI2NA, Nantes, France
| | - Benoit Guillet
- CRC-MH, CHU de Rennes, Rennes, France.,Univ Rennes, CHU Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, Rennes, France
| | - Marie C Béné
- Service d'Hématologie Biologique, CHU de Nantes, Nantes, France.,Nantes Université, Inserm UMR 1307, CNRS UMR 6075, Université d'Angers, CRCI2NA, Nantes, France
| | - Marc Fouassier
- Service d'Hématologie Biologique, CHU de Nantes, Nantes, France.,CRC-MH, CHU de Nantes, Nantes, France
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2
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Skalníková M, Staňo Kozubík K, Trizuljak J, Vrzalová Z, Radová L, Réblová K, Holbová R, Kurucová T, Svozilová H, Štika J, Blaháková I, Dvořáčková B, Prudková M, Stehlíková O, Šmída M, Křen L, Smejkal P, Pospíšilová Š, Doubek M. A GP1BA Variant in a Czech Family with Monoallelic Bernard-Soulier Syndrome. Int J Mol Sci 2022; 23:ijms23020885. [PMID: 35055070 PMCID: PMC8777725 DOI: 10.3390/ijms23020885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/05/2022] [Accepted: 01/10/2022] [Indexed: 12/14/2022] Open
Abstract
Bernard-Soulier syndrome (BSS) is a rare inherited disorder characterized by unusually large platelets, low platelet count, and prolonged bleeding time. BSS is usually inherited in an autosomal recessive (AR) mode of inheritance due to a deficiency of the GPIb-IX-V complex also known as the von Willebrand factor (VWF) receptor. We investigated a family with macrothrombocytopenia, a mild bleeding tendency, slightly lowered platelet aggregation tests, and suspected autosomal dominant (AD) inheritance. We have detected a heterozygous GP1BA likely pathogenic variant, causing monoallelic BSS. A germline GP1BA gene variant (NM_000173:c.98G > A:p.C33Y), segregating with the macrothrombocytopenia, was detected by whole-exome sequencing. In silico analysis of the protein structure of the novel GPIbα variant revealed a potential structural defect, which could impact proper protein folding and subsequent binding to VWF. Flow cytometry, immunoblot, and electron microscopy demonstrated further differences between p.C33Y GP1BA carriers and healthy controls. Here, we provide a detailed insight into its clinical presentation and phenotype. Moreover, the here described case first presents an mBSS patient with two previous ischemic strokes.
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Affiliation(s)
- Magdalena Skalníková
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
- Correspondence: (M.S.); (M.D.); Tel.: +421-54-949-8293 (M.S.)
| | - Kateřina Staňo Kozubík
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
| | - Jakub Trizuljak
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
- Institute of Medical Genetics and Genomics, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - Zuzana Vrzalová
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
| | - Lenka Radová
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
| | - Kamila Réblová
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
- Institute of Medical Genetics and Genomics, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - Radka Holbová
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
| | - Terézia Kurucová
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
| | - Hana Svozilová
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
- Institute of Medical Genetics and Genomics, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - Jiří Štika
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
| | - Ivona Blaháková
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
| | - Barbara Dvořáčková
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
| | - Marie Prudková
- Department of Clinical Hematology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (M.P.); (P.S.)
- Department of Laboratory Methods, Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - Olga Stehlíková
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
| | - Michal Šmída
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
| | - Leoš Křen
- Department of Pathology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic;
| | - Petr Smejkal
- Department of Clinical Hematology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (M.P.); (P.S.)
- Department of Laboratory Methods, Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - Šárka Pospíšilová
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
- Institute of Medical Genetics and Genomics, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - Michael Doubek
- Center of Molecular Medicine, Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic; (K.S.K.); (J.T.); (Z.V.); (L.R.); (K.R.); (R.H.); (T.K.); (H.S.); (J.Š.); (I.B.); (M.Š.); (Š.P.)
- Department of Internal Medicine, Hematology and Oncology, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; (B.D.); (O.S.)
- Institute of Medical Genetics and Genomics, University Hospital Brno and Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
- Correspondence: (M.S.); (M.D.); Tel.: +421-54-949-8293 (M.S.)
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Dunstan-Harrison C, Morison IM, Ledgerwood EC. A novel frameshift GP1BB mutation causes autosomal dominant macrothrombocytopenia with decreased vWF receptor expression but normal platelet aggregation. Platelets 2021; 33:324-327. [PMID: 33813986 DOI: 10.1080/09537104.2021.1909716] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
GP1bβ is a component of the von Willebrand factor (vWF) receptor complex that is necessary for platelet formation and activation. A novel frameshift variant in GP1BB has been identified in a family with macrothrombocytopenia. The variant leads to a protein that is 101 amino acids longer than wild type with loss of the transmembrane domain. As there is no defect in platelet aggregation, the family are classified as heterozygous carriers of a Bernard-Soulier syndrome-related mutation. The levels of the vWF receptor on platelets are reduced to 50% of the controls, with the presence of large platelets but normal platelet aggregation demonstrating that decreased vWF receptor expression impacts proplatelet formation but not platelet function.
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Affiliation(s)
| | - Ian M Morison
- Departments of Pathology, University of Otago, Dunedin, New Zealand
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4
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Guéguen P, Dupuis A, Py JY, Desprès A, Masson E, Le Marechal C, Cooper DN, Gachet C, Chen JM, Férec C. Pathogenic and likely pathogenic variants in at least five genes account for approximately 3% of mild isolated nonsyndromic thrombocytopenia. Transfusion 2020; 60:2419-2431. [PMID: 32757236 DOI: 10.1111/trf.15992] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 06/12/2020] [Accepted: 06/15/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Thrombocytopenia has a variety of different etiologies, both acquired and hereditary. Inherited thrombocytopenia may be associated with other symptoms (syndromic forms) or may be strictly isolated. To date, only about half of all the familial forms of thrombocytopenia have been accounted for in terms of well-defined genetic abnormalities. However, data are limited on the nature and frequency of the underlying causative genetic variants in individuals with mild isolated nonsyndromic thrombocytopenia. STUDY DESIGN AND METHODS Thirteen known or candidate genes for isolated thrombocytopenia were included in a gene panel analysis in which targeted next-generation sequencing was performed on 448 French blood donors with mild isolated nonsyndromic thrombocytopenia. RESULTS A total of 68 rare variants, including missense, splice site, frameshift, nonsense, and in-frame variants (all heterozygous) were identified in 11 of the 13 genes screened. Twenty-nine percent (N = 20) of the variants detected were absent from both the French Exome Project and gnomAD exome databases. Using stringent criteria and an unbiased approach, we classified seven predicted loss-of-function variants (three in ITGA2B and four in TUBB1) and four missense variants (one in GP1BA, two in ITGB3 and one in ACTN1) as being pathogenic or likely pathogenic. Altogether, they were found in 13 members (approx. 3%) of our studied cohort. CONCLUSION We present the results of gene panel sequencing of known and candidate thrombocytopenia genes in mild isolated nonsyndromic thrombocytopenia. Pathogenic and likely pathogenic variants in five known thrombocytopenia genes were identified, accounting for approximately 3% of individuals with the condition.
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Affiliation(s)
- Paul Guéguen
- CHRU Brest, Brest, France.,EFS, Univ Brest, Inserm, UMR 1078, GGB, Brest, France
| | - Arnaud Dupuis
- Université de Strasbourg, Institut National de la Santé et de la Recherche Médicale, Etablissement Français du Sang Grand Est, Unité Mixte de Recherche-S 1255, Fédération de Médecine Translationnelle de Strasbourg, Strasbourg, France
| | - Jean-Yves Py
- EFS Centre-Pays de la Loire, Site d'Orléans, Orléans, France
| | | | - Emmanuelle Masson
- CHRU Brest, Brest, France.,EFS, Univ Brest, Inserm, UMR 1078, GGB, Brest, France
| | - Cédric Le Marechal
- CHRU Brest, Brest, France.,EFS, Univ Brest, Inserm, UMR 1078, GGB, Brest, France
| | - David N Cooper
- Institute of Medical Genetics, School of Medicine, Cardiff University, Cardiff, UK
| | - Christian Gachet
- Université de Strasbourg, Institut National de la Santé et de la Recherche Médicale, Etablissement Français du Sang Grand Est, Unité Mixte de Recherche-S 1255, Fédération de Médecine Translationnelle de Strasbourg, Strasbourg, France
| | | | - Claude Férec
- CHRU Brest, Brest, France.,EFS, Univ Brest, Inserm, UMR 1078, GGB, Brest, France
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Matsushima N, Takatsuka S, Miyashita H, Kretsinger RH. Leucine Rich Repeat Proteins: Sequences, Mutations, Structures and Diseases. Protein Pept Lett 2019; 26:108-131. [PMID: 30526451 DOI: 10.2174/0929866526666181208170027] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 11/26/2018] [Accepted: 11/26/2018] [Indexed: 12/18/2022]
Abstract
Mutations in the genes encoding Leucine Rich Repeat (LRR) containing proteins are associated with over sixty human diseases; these include high myopia, mitochondrial encephalomyopathy, and Crohn's disease. These mutations occur frequently within the LRR domains and within the regions that shield the hydrophobic core of the LRR domain. The amino acid sequences of fifty-five LRR proteins have been published. They include Nod-Like Receptors (NLRs) such as NLRP1, NLRP3, NLRP14, and Nod-2, Small Leucine Rich Repeat Proteoglycans (SLRPs) such as keratocan, lumican, fibromodulin, PRELP, biglycan, and nyctalopin, and F-box/LRR-repeat proteins such as FBXL2, FBXL4, and FBXL12. For example, 363 missense mutations have been identified. Replacement of arginine, proline, or cysteine by another amino acid, or the reverse, is frequently observed. The diverse effects of the mutations are discussed based on the known structures of LRR proteins. These mutations influence protein folding, aggregation, oligomerization, stability, protein-ligand interactions, disulfide bond formation, and glycosylation. Most of the mutations cause loss of function and a few, gain of function.
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Affiliation(s)
- Norio Matsushima
- Center for Medical Education, Sapporo Medical University, Sapporo 060-8556, Japan.,Institute of Tandem Repeats, Noboribetsu 059-0464, Japan
| | - Shintaro Takatsuka
- Center for Medical Education, Sapporo Medical University, Sapporo 060-8556, Japan
| | - Hiroki Miyashita
- Institute of Tandem Repeats, Noboribetsu 059-0464, Japan.,Hokubu Rinsho Co., Ltd, Sapporo 060-0061, Japan
| | - Robert H Kretsinger
- Department of Biology, University of Virginia, Charlottesville, VA 22904, United States
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6
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Saad MN, Mabrouk MS, Eldeib AM, Shaker OG. Studying the effects of haplotype partitioning methods on the RA-associated genomic results from the North American Rheumatoid Arthritis Consortium (NARAC) dataset. J Adv Res 2019; 18:113-126. [PMID: 30891314 PMCID: PMC6403413 DOI: 10.1016/j.jare.2019.01.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 01/03/2019] [Accepted: 01/14/2019] [Indexed: 12/16/2022] Open
Abstract
Haplotype blocks methods plays a complementary role to the single-SNP approaches. CIT, FGT, SSLD, and single-SNP methods should be applied to discover the markers. Selection of the method used for the association has an impact on the biomarkers. SSLD method detected more significant SNPs than CIT, FGT, and single-SNP methods. The 383 SNPs discovered by all methods are significantly associated with RA.
The human genome, which includes thousands of genes, represents a big data challenge. Rheumatoid arthritis (RA) is a complex autoimmune disease with a genetic basis. Many single-nucleotide polymorphism (SNP) association methods partition a genome into haplotype blocks. The aim of this genome wide association study (GWAS) was to select the most appropriate haplotype block partitioning method for the North American Rheumatoid Arthritis Consortium (NARAC) dataset. The methods used for the NARAC dataset were the individual SNP approach and the following haplotype block methods: the four-gamete test (FGT), confidence interval test (CIT), and solid spine of linkage disequilibrium (SSLD). The measured parameters that reflect the strength of the association between the biomarker and RA were the P-value after Bonferroni correction and other parameters used to compare the output of each haplotype block method. This work presents a comparison among the individual SNP approach and the three haplotype block methods to select the method that can detect all the significant SNPs when applied alone. The GWAS results from the NARAC dataset obtained with the different methods are presented. The individual SNP, CIT, FGT, and SSLD methods detected 541, 1516, 1551, and 1831 RA-associated SNPs respectively, and the individual SNP, FGT, CIT, and SSLD methods detected 65, 156, 159, and 450 significant SNPs respectively, that were not detected by the other methods. Three hundred eighty-three SNPs were discovered by the haplotype block methods and the individual SNP approach, while 1021 SNPs were discovered by all three haplotype block methods. The 383 SNPs detected by all the methods are promising candidates for studying RA susceptibility. A hybrid technique involving all four methods should be applied to detect the significant SNPs associated with RA in the NARAC dataset, but the SSLD method may be preferred because of its advantages when only one method was used.
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Affiliation(s)
- Mohamed N Saad
- Biomedical Engineering Department, Faculty of Engineering, Minia University, Minia, Egypt
| | - Mai S Mabrouk
- Biomedical Engineering Department, Faculty of Engineering, Misr University for Science and Technology, 6th of October City, Egypt
| | - Ayman M Eldeib
- Systems and Biomedical Engineering Department, Faculty of Engineering, Cairo University, Giza, Egypt
| | - Olfat G Shaker
- Medical Biochemistry and Molecular Biology Department, Faculty of Medicine, Cairo University, Cairo, Egypt
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7
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Sivapalaratnam S, Westbury SK, Stephens JC, Greene D, Downes K, Kelly AM, Lentaigne C, Astle WJ, Huizinga EG, Nurden P, Papadia S, Peerlinck K, Penkett CJ, Perry DJ, Roughley C, Simeoni I, Stirrups K, Hart DP, Tait RC, Mumford AD, Laffan MA, Freson K, Ouwehand WH, Kunishima S, Turro E. Rare variants in GP1BB are responsible for autosomal dominant macrothrombocytopenia. Blood 2017; 129:520-524. [PMID: 28064200 PMCID: PMC6037295 DOI: 10.1182/blood-2016-08-732248] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 11/03/2016] [Indexed: 02/04/2023] Open
Abstract
The von Willebrand receptor complex, which is composed of the glycoproteins Ibα, Ibβ, GPV, and GPIX, plays an essential role in the earliest steps in hemostasis. During the last 4 decades, it has become apparent that loss of function of any 1 of 3 of the genes encoding these glycoproteins (namely, GP1BA, GP1BB, and GP9) leads to autosomal recessive macrothrombocytopenia complicated by bleeding. A small number of variants in GP1BA have been reported to cause a milder and dominant form of macrothrombocytopenia, but only 2 tentative reports exist of such a variant in GP1BB By analyzing data from a collection of more than 1000 genome-sequenced patients with a rare bleeding and/or platelet disorder, we have identified a significant association between rare monoallelic variants in GP1BB and macrothrombocytopenia. To strengthen our findings, we sought further cases in 2 additional collections in the United Kingdom and Japan. Across 18 families exhibiting phenotypes consistent with autosomal dominant inheritance of macrothrombocytopenia, we report on 27 affected cases carrying 1 of 9 rare variants in GP1BB.
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Affiliation(s)
- Suthesh Sivapalaratnam
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
- Department of Haematology, Barts Health National Health Service Trust, London, United Kingdom
| | - Sarah K Westbury
- School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
| | - Jonathan C Stephens
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
- National Health Service Blood and Transplant, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Daniel Greene
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
- Medical Research Council Biostatistics Unit, Cambridge Institute of Public Health, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Kate Downes
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
- National Health Service Blood and Transplant, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Anne M Kelly
- Department of Haematology, Great Ormond Street Hospital for Children National Health Service Trust, London, United Kingdom
| | - Claire Lentaigne
- Centre for Haematology, Hammersmith Campus, Imperial College Academic Health Sciences Centre, Imperial College London, London, United Kingdom
- Imperial College Healthcare National Health Service Trust, London, United Kingdom
| | - William J Astle
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
- Medical Research Council Biostatistics Unit, Cambridge Institute of Public Health, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Eric G Huizinga
- Crystal and Structural Chemistry, Department of Chemistry, Faculty of Science, Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands
| | - Paquita Nurden
- Institut Hospitalo-Universitaire LIRYC, Hôpital Xavier Arnozan, Pessac, France
| | - Sofia Papadia
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
| | - Kathelijne Peerlinck
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Christopher J Penkett
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
| | - David J Perry
- Department of Haematology, Addenbrooke's Hospital, Cambridge University Hospitals National Health Service Foundation Trust, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Catherine Roughley
- Kent Haemophilia Thrombosis Centre at East Kent Hospitals University NHS Foundation Trust, Canterbury, United Kingdom
| | - Ilenia Simeoni
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
- National Health Service Blood and Transplant, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Kathleen Stirrups
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
| | - Daniel P Hart
- Department of Haematology, Barts Health National Health Service Trust, London, United Kingdom
| | - R Campbell Tait
- Department of Haematology, Royal Infirmary, Glasgow, United Kingdom
| | - Andrew D Mumford
- School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
- School of Cellular and Molecular Medicine, University of Bristol, Bristol, United Kingdom
| | - Michael A Laffan
- Centre for Haematology, Hammersmith Campus, Imperial College Academic Health Sciences Centre, Imperial College London, London, United Kingdom
- Imperial College Healthcare National Health Service Trust, London, United Kingdom
| | - Kathleen Freson
- Department of Cardiovascular Sciences, Center for Molecular and Vascular Biology, University of Leuven, Leuven, Belgium
| | - Willem H Ouwehand
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
- National Health Service Blood and Transplant, Cambridge Biomedical Campus, Cambridge, United Kingdom
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom; and
| | - Shinji Kunishima
- Department of Advanced Diagnosis, Clinical Research Center, National Hospital Organization Nagoya Medical Center, Nagoya, Japan
| | - Ernest Turro
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- National Institute for Health Research BioResource-Rare Diseases, Cambridge University Hospitals, Cambridge, United Kingdom
- National Health Service Blood and Transplant, Cambridge Biomedical Campus, Cambridge, United Kingdom
- Medical Research Council Biostatistics Unit, Cambridge Institute of Public Health, Cambridge Biomedical Campus, Cambridge, United Kingdom
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8
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Ali S, Ghosh K, Daly ME, Hampshire DJ, Makris M, Ghosh M, Mukherjee L, Bhattacharya M, Shetty S. Congenital macrothrombocytopenia is a heterogeneous disorder in India. Haemophilia 2016; 22:570-82. [DOI: 10.1111/hae.12917] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/11/2016] [Indexed: 11/27/2022]
Affiliation(s)
- S. Ali
- Department of Haemostasis and Thrombosis; National Institute of Immunohaematology; Parel, Mumbai
| | - K. Ghosh
- Surat Raktadan Kendra; Surat; Gujarat India
| | - M. E. Daly
- Department of Cardiovascular Science; Medical School; University of Sheffield; Sheffield UK
| | - D. J. Hampshire
- Department of Cardiovascular Science; Medical School; University of Sheffield; Sheffield UK
| | - M. Makris
- Department of Cardiovascular Science; Medical School; University of Sheffield; Sheffield UK
| | - M. Ghosh
- Department of Haematology; NRS Medical College and Hospital; Kolkata India
| | - L. Mukherjee
- Department of Haematology; NRS Medical College and Hospital; Kolkata India
| | - M. Bhattacharya
- Department of Haematology; NRS Medical College and Hospital; Kolkata India
| | - S. Shetty
- Department of Haemostasis and Thrombosis; National Institute of Immunohaematology; Parel, Mumbai
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9
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Baccini V, Alessi MC. [Diagnosis of inherited thrombocytopenia]. Rev Med Interne 2015; 37:117-26. [PMID: 26617290 DOI: 10.1016/j.revmed.2015.10.346] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 10/19/2015] [Indexed: 12/19/2022]
Abstract
Inherited thrombocytopenias are rare, heterogenous and probably under-diagnosed because often classified as autoimmune thrombocytopenia. About 20 genes were described responsible for these thrombocytopenias. Precise diagnosis is necessary because the prognosis is different and some of them can evolve into hemopathies. First of all, it is important to gather a body of evidence to orientate towards an inherited cause: presence of the thrombocytopenia since childhood and of other family cases is a strong argument. Secondly, it is difficult to target the genetic investigations that settle the precise diagnosis. Genetic variants responsible for inherited thrombocytopenias affect different stage during megakaryocytopoiesis and cause thrombocytopenias with distinct characteristics. Presence of extra-hematological features, platelets' size measurement and evaluation of bone marrow megakaryocyte morphology when it is possible allow a primary orientation. We propose a diagnostic approach considering extra-hematological features, mode of inheritance, morphology, molecular and functional platelets' studies and bone marrow megakaryocyte morphology in order to better target genetic study. Nevertheless, despite this approach, some inherited thrombocytopenias remain still unexplained and could benefit from new methods of new generation sequencing in the future.
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Affiliation(s)
- V Baccini
- Laboratoire d'hématologie, hôpital Nord, CHU de Marseille, chemin des Bourrelly, 13015 Marseille, France; Centre de référence des pathologies plaquettaires (CRPP), CHU Timone, 264, rue Saint-Pierre, 13385 Marseille cedex 5, France.
| | - M C Alessi
- Laboratoire d'hématologie, hôpital Nord, CHU de Marseille, chemin des Bourrelly, 13015 Marseille, France; Centre de référence des pathologies plaquettaires (CRPP), CHU Timone, 264, rue Saint-Pierre, 13385 Marseille cedex 5, France
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10
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Savoia A, Kunishima S, De Rocco D, Zieger B, Rand ML, Pujol-Moix N, Caliskan U, Tokgoz H, Pecci A, Noris P, Srivastava A, Ward C, Morel-Kopp MC, Alessi MC, Bellucci S, Beurrier P, de Maistre E, Favier R, Hézard N, Hurtaud-Roux MF, Latger-Cannard V, Lavenu-Bombled C, Proulle V, Meunier S, Négrier C, Nurden A, Randrianaivo H, Fabris F, Platokouki H, Rosenberg N, HadjKacem B, Heller PG, Karimi M, Balduini CL, Pastore A, Lanza F. Spectrum of the mutations in Bernard-Soulier syndrome. Hum Mutat 2014; 35:1033-45. [PMID: 24934643 DOI: 10.1002/humu.22607] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Accepted: 06/06/2014] [Indexed: 01/05/2023]
Abstract
Bernard-Soulier syndrome (BSS) is a rare autosomal recessive bleeding disorder characterized by defects of the GPIb-IX-V complex, a platelet receptor for von Willebrand factor (VWF). Most of the mutations identified in the genes encoding for the GP1BA (GPIbα), GP1BB (GPIbβ), and GP9 (GPIX) subunits prevent expression of the complex at the platelet membrane or more rarely its interaction with VWF. As a consequence, platelets are unable to adhere to the vascular subendothelium and agglutinate in response to ristocetin. In order to collect information on BSS patients, we established an International Consortium for the study of BSS, allowing us to enrol and genotype 132 families (56 previously unreported). With 79 additional families for which molecular data were gleaned from the literature, the 211 families characterized so far have mutations in the GP1BA (28%), GP1BB (28%), or GP9 (44%) genes. There is a wide spectrum of mutations with 112 different variants, including 22 novel alterations. Consistent with the rarity of the disease, 85% of the probands carry homozygous mutations with evidence of founder effects in some geographical areas. This overview provides the first global picture of the molecular basis of BSS and will lead to improve patient diagnosis and management.
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Affiliation(s)
- Anna Savoia
- Institute for Maternal and Child Health - IRCCS "Burlo Garofolo", Trieste, Italy; Department of Medical Sciences, University of Trieste, Trieste, Italy
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11
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Abstract
The diagnosis of inherited thrombocytopenias is difficult, for many reasons. First, as they are all rare diseases, they are little known by clinicians, who therefore tend to suspect the most common forms. Second, making a definite diagnosis often requires complex laboratory techniques that are available in only a few centers. Finally, half of the patients have forms that have not yet been described. As a consequence, many patients with inherited thrombocytopenias are misdiagnosed with immune thrombocytopenia, and are at risk of receiving futile treatments. Misdiagnosis is particularly frequent in patients whose low platelet count is discovered in adult life, because, in these cases, even the inherited origin of thrombocytopenia may be missed. Making the correct diagnosis promptly is important, as we recently learned that some forms of inherited thrombocytopenia predispose to other illnesses, such as leukemia or kidney failure, and affected subjects therefore require close surveillance and, if necessary, prompt treatments. Moreover, medical treatment can increase platelet counts in specific disorders, and affected subjects can therefore receive drugs instead of platelet transfusions when selective surgery is required. In this review, we will discuss how to suspect, diagnose and manage inherited thrombocytopenias, with particular attention to the forms that frequently present in adults. Moreover, we describe four recently identified disorders that belong to this group of disorders that are often diagnosed in adults: MYH9-related disease, monoallelic Bernard-Soulier syndrome, ANKRD26-related thrombocytopenia, and familial platelet disorder with predisposition to acute leukemia.
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Affiliation(s)
- C L Balduini
- Department of Internal Medicine, University of Pavia-IRCCS Policlinico San Matteo Foundation, Pavia, Italy.
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12
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Novel Bernard-Soulier syndrome variants caused by compound heterozygous mutations (case I) or a cytoplasmic tail truncation (case II) of GPIbα. Thromb Res 2013; 131:e160-7. [DOI: 10.1016/j.thromres.2013.01.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 11/28/2012] [Accepted: 01/09/2013] [Indexed: 11/21/2022]
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13
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Quaternary organization of GPIb-IX complex and insights into Bernard-Soulier syndrome revealed by the structures of GPIbβ and a GPIbβ/GPIX chimera. Blood 2011; 118:5292-301. [PMID: 21908432 DOI: 10.1182/blood-2011-05-356253] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Platelet GPIb-IX receptor complex has 3 subunits GPIbα, GPIbβ, and GPIX, which assemble with a ratio of 1:2:1. Dysfunction in surface expression of the complex leads to Bernard-Soulier syndrome. We have crystallized the GPIbβ ectodomain (GPIbβ(E)) and determined the structure to show a single leucine-rich repeat with N- and C-terminal disulphide-bonded capping regions. The structure of a chimera of GPIbβ(E) and 3 loops (a,b,c) taken from the GPIX ectodomain sequence was also determined. The chimera (GPIbβ(Eabc)), but not GPIbβ(E), forms a tetramer in the crystal, showing a quaternary interface between GPIbβ and GPIX. Central to this interface is residue Tyr106 from GPIbβ, which inserts into a pocket generated by 2 loops (b,c) from GPIX. Mutagenesis studies confirmed this interface as a valid representation of interactions between GPIbβ and GPIX in the full-length complex. Eight GPIbβ missense mutations identified from patients with Bernard-Soulier syndrome were examined for changes to GPIb-IX complex surface expression. Two mutations, A108P and P74R, were found to maintain normal secretion/folding of GPIbβ(E) but were unable to support GPIX surface expression. The close structural proximity of these mutations to Tyr106 and the GPIbβ(E) interface with GPIX indicates they disrupt the quaternary organization of the GPIb-IX complex.
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14
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The same genetic defect in three Tunisian families with Bernard Soulier syndrome: a probable founder Stop mutation in GPIbbeta. Ann Hematol 2009; 89:75-81. [DOI: 10.1007/s00277-009-0763-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2008] [Accepted: 05/14/2009] [Indexed: 11/24/2022]
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15
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Kunishima S, Sako M, Yamazaki T, Hamaguchi M, Saito H. Molecular genetic analysis of a variant Bernard?Soulier syndrome due to compound heterozygosity for two novel glycoprotein Ib? mutations. Eur J Haematol 2006; 77:501-12. [PMID: 16978236 DOI: 10.1111/j.0902-4441.2006.t01-1-ejh2817.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bernard-Soulier syndrome (BSS) is a rare bleeding disorder characterized by giant platelets, thrombocytopenia, and prolonged bleeding time. It is caused by abnormalities in the glycoprotein (GP) Ib/IX/V complex, the receptor for von Willebrand factor (vWF). Most cases of BSS described so far involve quantitative rather than qualitative defects in the complex. In this study, we investigated the effects of two naturally occurring mutations in the GPIbbeta gene, C122S and 443delG, on the expression of the GPIb/IX complex identified in a variant type of BSS in which the platelets had severely reduced GPIbalpha ( approximately 10%) and less markedly reduced GPIbbeta and GPIX ( approximately 20%) expression. Immunoblot analysis showed the absence of non-reduced GPIb (GPIbalpha/GPIbbeta) in the patient's platelets. Transient transfection experiments in 293T cells revealed the expression of GPIbbeta Ser122 polypeptide and absence of GPIbbeta 443delG polypeptide. Although no disulfide-linked association was observed between GPIbbeta Ser122 and GPIbalpha, GPIbbeta Ser122 was non-covalently associated with both GPIbalpha and GPIX subunits on the cell surface when cotransfected with wild-type GPIbalpha and GPIX. Chinese hamster ovary cells stably expressing GPIbalpha/Ibbeta Ser122/IX had the ability to bind soluble vWF and to aggregate in the presence of ristocetin. These results suggest that despite disruption of the disulfide linkage between GPIbalpha and GPIbbeta, GPIb/IX is formed, but its stability may be impaired, resulting in low levels of the complex on the platelet membranes.
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Affiliation(s)
- Shinji Kunishima
- Department of Hemostasis and Thrombosis, Clinical Research Center, National Hospital Organization Nagoya Medical Center, Nagoya, Japan.
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16
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Lanza F. Bernard-Soulier syndrome (hemorrhagiparous thrombocytic dystrophy). Orphanet J Rare Dis 2006; 1:46. [PMID: 17109744 PMCID: PMC1660532 DOI: 10.1186/1750-1172-1-46] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2006] [Accepted: 11/16/2006] [Indexed: 11/29/2022] Open
Abstract
Bernard-Soulier syndrome (BSS), also known as Hemorrhagiparous thrombocytic dystrophy, is a hereditary bleeding disorder affecting the megakaryocyte/platelet lineage and characterized by bleeding tendency, giant blood platelets and low platelet counts. This syndrome is extremely rare as only approximately 100 cases have been reported in the literature. Clinical manifestations usually include purpura, epistaxis, menorrhagia, gingival and gastrointestinal bleeding. The syndrome is transmitted as an autosomal recessive trait. The underlying defect is a deficiency or dysfunction of the glycoprotein GPIb-V-IX complex, a platelet-restricted multisubunit receptor required for normal primary hemostasis. The GPIb-V-IX complex binds von Willebrand factor, allowing platelet adhesion and platelet plug formation at sites of vascular injury. Genes coding for the four subunits of the receptor, GPIBA, GPIBB, GP5 and GP9, map to chromosomes 17p12, 22q11.2, 3q29, and 3q21, respectively. Defects have been identified in GPIBA, GPIBB, and GP9 but not in GP5. Diagnosis is based on a prolonged skin bleeding time, the presence of a small number of very large platelets (macrothrombocytopenia), defective ristocetin-induced platelet agglutination and low or absent expression of the GPIb-V-IX complex. Prothrombin consumption is markedly reduced. The prognosis is usually good with adequate supportive care but severe bleeding episodes can occur with menses, trauma and surgical procedures. Treatment of bleeding or prophylaxis during surgical procedures usually requires platelet transfusion.
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17
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Strassel C, David T, Eckly A, Baas MJ, Moog S, Ravanat C, Trzeciak MC, Vinciguerra C, Cazenave JP, Gachet C, Lanza F. Synthesis of GPIb beta with novel transmembrane and cytoplasmic sequences in a Bernard-Soulier patient resulting in GPIb-defective signaling in CHO cells. J Thromb Haemost 2006; 4:217-28. [PMID: 16409472 DOI: 10.1111/j.1538-7836.2005.01654.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The molecular defect of a new Bernard-Soulier patient, originating from Morocco and presenting thrombocytopenia with large platelets and an absence of ristocetin-induced platelet agglutination, has been identified and reproduced in transfected heterologous cells. Gene sequencing revealed insertion of a guanine in the domain coding for the transmembrane region of the glycoprotein (GP) Ib beta subunit. This mutation causes a translational frame shift, which creates putative novel transmembrane and cytoplasmic 37 and 125 amino acids domains, respectively. A 34 kDa immunoreactive GPIb beta band, instead of the normal 26 kDa subunit, was detected by Western blotting in lysates from the patient's platelets and from transfected cells and in immunoprecipitates of metabolically labeled cells. The abnormal subunit did not associate with GPIb alpha and was mainly intracellular, although a significant fraction could reach the cell surface. Cells expressing the mutant GPIb-IX complex adhered to a von Willebrand factor matrix but were unable to change shape, unlike cells expressing the wild-type receptor. These results strongly suggest a novel role of the GPIb beta subunit and its transmembrane-intracellular region in GPIb-VWF-dependent signaling, in addition to a role in correct assembly and cell surface targeting of the GPIb-V-IX complex.
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Affiliation(s)
- C Strassel
- INSERM U.311, Etablissement Français du Sang, Alsace, Strasbourg, France
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18
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Pallotta R, Evangelista V, Margaglione M, Bucci I, Saponari A. Macrothrombocytopenia in velocardiofacial syndrome. J Thromb Haemost 2005; 3:601-3. [PMID: 15748265 DOI: 10.1111/j.1538-7836.2005.01202.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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19
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Strassel C, Alessi MC, Juhan-Vague I, Cazenave JP, Lanza F. A 13 base pair deletion in the GPIbbeta gene in a second unrelated Bernard-Soulier family due to slipped mispairing between direct repeats. J Thromb Haemost 2004; 2:1663-5. [PMID: 15333045 DOI: 10.1111/j.1538-7836.2004.00895.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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20
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Kato K, Martinez C, Russell S, Nurden P, Nurden A, Fiering S, Ware J. Genetic deletion of mouse platelet glycoprotein Ibbeta produces a Bernard-Soulier phenotype with increased alpha-granule size. Blood 2004; 104:2339-44. [PMID: 15213102 DOI: 10.1182/blood-2004-03-1127] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Here we report the characterization of a mouse model of the Bernard-Soulier syndrome generated by a targeted disruption of the gene encoding the glycoprotein (GP) Ibbeta subunit of the GP Ib-IX complex. Similar to a Bernard-Soulier model generated by disruption of the mouse GP Ibalpha subunit, GP Ibbeta(Null) mice display macrothrombocytopenia and a severe bleeding phenotype. When examined by transmission electron microscopy, the large platelets produced by a GP Ibbeta(Null) genotype revealed alpha-granules with increased size as compared with the alpha-granules from control mouse platelets. Data are presented linking the overexpression of a septin protein, SEPT5, to the presence of larger alpha-granules in the GP Ibbeta(Null) platelet. The SEPT5 gene resides approximately 250 nucleotides 5' to the GP Ibbeta gene and has been associated with modulating exocytosis from neurons and platelets as part of a presynaptic protein complex. Fusion mRNA transcripts present in megakaryocytes can contain both the SEPT5 and GP Ibbeta coding sequences as a result in an imperfect polyadenylation signal within the 3' end of both the human and mouse SEPT5 genes. We observed a 2- to 3-fold increase in SEPT5 protein levels in platelets from GP Ibbeta(Null) mice. These results implicate SEPT5 levels in the maintenance of normal alpha-granule size and may explain the variant granules associated with human GP Ibbeta mutations and the Bernard-Soulier syndrome.
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Affiliation(s)
- Kazunobu Kato
- University of Arkansas for Medical Sciences, 4301 W Markham St, Little Rock, AR 72205, USA
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21
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Nurden AT, Combrié R, Claeyssens S, Nurden P. Heterozygotes in the bernard-soulier syndrome do not necessarily have giant platelets or thrombocytopenia. Br J Haematol 2003; 120:716-7. [PMID: 12588363 DOI: 10.1046/j.1365-2141.2003.04132_1.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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22
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Abstract
Bernard-Soulier Syndrome (BSS) is an autosomal recessive bleeding disorder due to quantitative or qualitative abnormalities in the glycoprotein (GP) Ib/IX/V complex, the platelet receptor for von Willebrand factor. BSS is characterized by giant platelets, thrombocytopenia, and prolonged bleeding time, and the hallmark of this disorder is the absence of ristocetin-induced platelet agglutination. In the last 10 years, the molecular and genetic bases of many GPIb/IX/V defects have been elucidated, providing a better understanding of primary hemostasis and structure-function relations of the complex. Thus far, more than 30 mutations of the GPIbalpha, GPIbbeta, or GPIX genes have been described in BSS. Recent studies also have shown that the phenotypes caused by mutations in the subunits of the GPIb/IX/V span a wide spectrum, from the normal phenotype, to isolated giant platelet disorders/macrothrombocytopenia, to full-blown BSS and platelet-type von Willebrand disease. Although recent progress in molecular biology has clarified the genotype-phenotype relationships of the GPIb/IX/V disorders, a close examination of platelet morphology on blood smears is still indispensable for a proper diagnosis. In this review, we summarize recent advances in the molecular basis of BSS with special emphasis on giant platelets and the genetic characteristics of Japanese BSS.
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