title: Genotype-phenotype correlation in a cohort of Portuguese patients comprising the entire spectrum of VWD types: impact of NGS.
abstract: The diagnosis of von Willebrand disease (VWD), the most common inherited bleeding disorder, is characterised by a variable bleeding tendency and heterogeneous laboratory phenotype. The sequencing of the entire VWF coding region has not yet become a routine practice in diagnostic laboratories owing to its high costs. Nevertheless, next-generation sequencing (NGS) has emerged as an alternative to overcome this limitation. We aimed to determine the correlation of genotype and phenotype in 92 Portuguese individuals from 60 unrelated families with VWD; therefore, we directly sequenced VWF. We compared the classical Sanger sequencing approach and NGS to assess the value-added effect on the analysis of the mutation distribution in different types of VWD. Sixty-two different VWF mutations were identified, 27 of which had not been previously described. NGS detected 26 additional mutations, contributing to a broad overview of the mutant alleles present in each VWD type. Twenty-nine probands (48.3 %) had two or more mutations; in addition, mutations with pleiotropic effects were detected, and NGS allowed an appropriate classification for seven of them. Furthermore, the differential diagnosis between VWD 2B and platelet type VWD (n = 1), Bernard-Soulier syndrome and VWD 2B (n = 1), and mild haemophilia A and VWD 2N (n = 2) was possible. NGS provided an efficient laboratory workflow for analysing VWF. These findings in our cohort of Portuguese patients support the proposal that improving VWD diagnosis strategies will enhance clinical and laboratory approaches, allowing to establish the most appropriate treatment for each patient.
authors.affiliation: Teresa Fidalgo, Centro Hospitalar e Universitário de Coimbra (CHUC), Serviço de Hematologia Clínica, Unidade de Trombose e Hemostase, Av Afonso Romão Coimbra 3000-602, Portugal, Tel.: +351 239 480 370, Fax: +351 239 717 216, E-mail: teresa.fidalgo@chuc.min-saude.pt.
authors.forename: Teresa
authors.initials: T
authors.lastname: Fidalgo
authors.forename: Ramon
authors.initials: R
authors.lastname: Salvado
authors.forename: Irene
authors.initials: I
authors.lastname: Corrales
authors.forename: Silva Catarina
authors.initials: SC
authors.lastname: Pinto
authors.forename: Nina
authors.initials: N
authors.lastname: Borràs
authors.forename: Ana
authors.initials: A
authors.lastname: Oliveira
authors.forename: Patricia
authors.initials: P
authors.lastname: Martinho
authors.forename: Gisela
authors.initials: G
authors.lastname: Ferreira
authors.forename: Helena
authors.initials: H
authors.lastname: Almeida
authors.forename: Cristina
authors.initials: C
authors.lastname: Oliveira
authors.forename: Dalila
authors.initials: D
authors.lastname: Marques
authors.forename: Elsa
authors.initials: E
authors.lastname: Gonçalves
authors.forename: MJoão
authors.initials: M
authors.lastname: Diniz
authors.forename: Margarida
authors.initials: M
authors.lastname: Antunes
authors.forename: Alice
authors.initials: A
authors.lastname: Tavares
authors.forename: Gonçalo
authors.initials: G
authors.lastname: Caetano
authors.forename: Paula
authors.initials: P
authors.lastname: Kjöllerström
authors.forename: Raquel
authors.initials: R
authors.lastname: Maia
authors.forename: Teresa S
authors.initials: TS
authors.lastname: Sevivas
authors.forename: Francisco
authors.initials: F
authors.lastname: Vidal
authors.forename: Leticia
authors.initials: L
authors.lastname: Ribeiro
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004252:DNA Mutational Analysis; D005260:Female; D056726:Genetic Association Studies; D014644:Genetic Variation; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009154:Mutation; D011174:Portugal; D017422:Sequence Analysis, DNA; D055815:Young Adult; D014842:von Willebrand Diseases / Q000145:classification / Q000175:diagnosis* / Q000235:genetics*; D014841:von Willebrand Factor / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D014841:von Willebrand Factor
keywords: Gene mutations; NGS; molecular biology methods; von Willebrand disease; von Willebrand factor