Thromb Haemost 2016; 116(06): 1070-1078
DOI: 10.1160/TH16-06-0438
Cellular Haemostasis and Platelets
Schattauer Publishers Schattauer

A novel platelet-type von Willebrand disease mutation (GP1BA p.Met255Ile) associated with type 2B “Malmö/New York” von Willebrand disease

Cécile Lavenu-Bombled
1   Service d’Hématologie Biologique, CHU Bicêtre, AP-HP, Université Paris Sud, Le Kremlin Bicêtre, France
8   INSERM UMR_S1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin-Bicêtre, France
10   Centre de Référence de la Maladie de Willebrand, France
11   Centre de Référence des Pathologies Plaquettaires, France
,
Corinne Guitton
2   Service de Rhumato-Hématologie Pédiatrique, CHU Bicêtre, AP-HP, Université Paris Sud, Le Kremlin Bicêtre, France
10   Centre de Référence de la Maladie de Willebrand, France
,
Arnaud Dupuis
3   UMR_S949 INSERM, Strasbourg, France
4   Etablissement Français du Sang (EFS)-ALCA, Strasbourg, France
5   Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
6   Université de Strasbourg, Strasbourg, France
11   Centre de Référence des Pathologies Plaquettaires, France
,
Marie-Jeanne Baas
3   UMR_S949 INSERM, Strasbourg, France
4   Etablissement Français du Sang (EFS)-ALCA, Strasbourg, France
5   Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
6   Université de Strasbourg, Strasbourg, France
,
Céline Desconclois
1   Service d’Hématologie Biologique, CHU Bicêtre, AP-HP, Université Paris Sud, Le Kremlin Bicêtre, France
10   Centre de Référence de la Maladie de Willebrand, France
11   Centre de Référence des Pathologies Plaquettaires, France
,
Marie Dreyfus
1   Service d’Hématologie Biologique, CHU Bicêtre, AP-HP, Université Paris Sud, Le Kremlin Bicêtre, France
10   Centre de Référence de la Maladie de Willebrand, France
11   Centre de Référence des Pathologies Plaquettaires, France
,
Renhao Li
7   Aflac Cancer and Blood Disorders Center, Department of Pediatrics, Children’s Healthcare of Atlanta and Emory University School of Medicine, Atlanta, Georgia, USA
,
Claudine Caron
9   Département d’Hématologie Transfusion, CHU Lille, France
10   Centre de Référence de la Maladie de Willebrand, France
,
Christian Gachet
3   UMR_S949 INSERM, Strasbourg, France
4   Etablissement Français du Sang (EFS)-ALCA, Strasbourg, France
5   Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
6   Université de Strasbourg, Strasbourg, France
11   Centre de Référence des Pathologies Plaquettaires, France
,
Edith Fressinaud
8   INSERM UMR_S1176, Université Paris-Sud, Université Paris-Saclay, Le Kremlin-Bicêtre, France
9   Département d’Hématologie Transfusion, CHU Lille, France
10   Centre de Référence de la Maladie de Willebrand, France
,
François Lanza
3   UMR_S949 INSERM, Strasbourg, France
4   Etablissement Français du Sang (EFS)-ALCA, Strasbourg, France
5   Fédération de Médecine Translationnelle de Strasbourg (FMTS), Strasbourg, France
6   Université de Strasbourg, Strasbourg, France
11   Centre de Référence des Pathologies Plaquettaires, France
› Author Affiliations
Further Information

Publication History

Received 08 June 2016

Accepted after major revision: 07 August 2016

Publication Date:
09 March 2018 (online)

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Summary

Interaction between von Willebrand factor (VWF) and platelet GPIbα is required for primary haemostasis. Lack or loss-of-function in the ligand-receptor pair results in bleeding complications. Paradoxically, gain-of-function mutations in VWF or GPIbα also result in bleeding complications as observed in type 2B von Willebrand disease (VWD) and platelet-type- (PT-) VWD, respectively. A similar phenotype is observed with increased ristocetin-induced platelet agglutination and disappearance of the highest molecular weight multimers of VWF. We evaluated a patient with a bleeding disorder and a biological presentation compatible with type 2B VWD. VWF and platelet functional assays, sequencing of the VWF and GP1BA genes, and expression studies in HEK cells were performed. Sequencing of the VWF gene in the propositus revealed a heterozygous p.Pro1266Leu mutation previously found in type 2B VWD Malmö/New York. These variants are characterised by a mild phenotype and a normal VWF multimer composition suggesting the presence of a second mutation in our propositus. Sequencing of the GP1BA gene revealed a heterozygous c.765G>A substitution changing Met at position 255 of GPIbα to Ile. This new mutation is located in the β-switch domain where five other gain-of-function mutations have been reported in PT-VWD. Expression of GPIbα Ile255 in HEK GPIb-IX cells resulted in enhanced VWF binding compared to wild-type, similar to known PT-VWD mutations (p.Val249, p.Ser249 and p.Val255) indicating that it contributes to the propositus defects. This first report associating PT-with type 2B VWD illustrates the importance of combining biological assays with genetic testing to better understand the clinical phenotype.