PO096 | IDENTIFICATION OF A NEW VARIANT IN THE RASGRP2 GENE IN A CHILD WITH SUSPECTED GLANZMANN THROMBASTHENIA

Abstract

Introduction. Congenital platelet disorders constitute a heterogeneous group of primary hemostatic defects that are often difficult to diagnose without an integrated approach that includes functional testing. We report the case of a child with suspected Glanzmann thrombasthenia, in whom a novel variant of the RasGRP2 gene (NM_001098671.2) was identified that cosegregates with the clinical phenotype.Methods. An 8-year-old boy, presenting with recurrent epistaxis and bruising and without a significant family history, was evaluated at our center. Initial tests showed normal PT and aPTT and impaired platelet function (PFA-100), suggesting a platelet disorder such as Glanzmann’s thrombasthenia. However, the absence of aggregation tests and flow cytometric analysis prevented a definitive differential diagnosis. To identify the genetic cause and confirm the suspected diagnosis, clinical exome sequencing (6,600 genes) was performed using the NextSeq 550 platform (Illumina). Bioinformatic analysis included filtering based on allele frequency (