Severe Bleeding Diathesis in Siblings with Platelet Dysfunction due to a Novel Nonsense RASGRP2 Mutation

Abstract

Next-generation sequencing is increasingly applied during the diagnostic work-up of patients with bleeding diathesis and has facilitated the diagnosis of rare bleeding disorders such as inherited platelet function disorders. Mutations in RAS guanyl releasing protein 2 (RasGRP2), also known as calcium- and diacylglycerol-regulated guanine nucleotide exchange factor I (CalDAG-GEFI), underlie a recently described platelet signal transduction abnormality. Here we present the case of a consanguineous family originating from Afghanistan with two siblings affected by recurrent severe mucocutaneous bleedings. Platelet function testing demonstrated a marked reduction of aggregation induced by collagen and adenosine diphosphate. Whole exome sequencing revealed a novel homozygous nonsense RASGRP2 mutation segregating with the bleeding disorder in the family.

Keywords

bleeding diathesis - platelet dysfunction - RASGRP2

Publikationsverlauf

Eingereicht: 25. März 2020

Angenommen: 15. September 2020

Artikel online veröffentlicht:
25. Dezember 2020

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