Identification of Diagnostic SNPs in Exon 28 of the Von Willebrand Factor Gene for Diagnosis of VWD Type 2B in Patients Referred to IBTO Coagulation Lab: In-silico Approach

Abstract

Background and Aims: von Willebrand disease (VWD) is brought on by hereditary impairments in the von Willebrand factor (VWF). It has been determined that most of the molecular abnormalities are present in exon 28 of the VWF gene qualitative variations. In this regard, investigating mutations in exon 28 of the VWF coding gene can help identify the VWD type and can be used to manage patients by using appropriate strategies.

Materials and Methods: 10 suspected VWD type 2B patients were investigated for the genotype of exon 28. Routine coagulation tests were performed for the patients. Molecular sequencing was also used for the evaluation of mutations in exon 28. Determining the tertiary structure of VWF can aid in understanding its functional residues and interactions. The nsSNVs’ pathogenicity was examined utilizing potent bioinformatics methods. Step-by-step testing of the high-risk mutations was done using SIFT, PolyPhen-2, I-Mutant 2.0, PHD-SNPg, and SNPs&GO. Then, the secondary structure, amino acid conservation, and feature of amino acids were investigated via Protparam, Cofactor, Interprosurf, ConSurf, NetSurfP-2.0, and HOPE.

Results: N1231T, V1229G, V1316M, and P1266Q missense mutations in VWF were detected. 3D structure of VWF predicted and evaluated. Putative conserved domains were identified. P1266Q and V1316M amino acid substitutions are predicted as “Not tolerated substitution” damaging and Disease, while V1229G and N1231T amino acid substitutions are predicted as “tolerated substitution” benign and Neutral.

Conclusion: V1316M and P1266Q amino acid substitutions were determined as high-risk mutations using powerful bioinformatics tools in VWD patients.