Whole Exome Sequencing in Severe Aplastic Anemia Identifies Unrecognized Inherited Subset with Inferior Survival after Hematopoietic Cell Transplant

Background: It is important to identify inherited bone marrow failure syndromes (IBMFS) in patients with aplastic anemia in order to provide appropriate therapy. IBMFS are diagnosed through genetic or other diagnostic testing but can also go unrecognized, particularly in adults who may lack classic IBMFS features. This is particularly critical in light of increasing identification of individuals with variants of uncertain significance (VUS) and those with single pathogenic variants in an autosomal recessive (AR) gene or X-linked recessive (XLR) gene in females (SPVR) (“carriers”) during evaluation. In this study of patients diagnosed with acquired severe aplastic anemia (SAA), we evaluated putatively causal variants in IBMFS genes to determine the frequency of patients with an unrecognized IBMFS or SPVR and assessed their association with outcomes after hematopoietic cell transplant (HCT).