SOX17 and hereditary elliptocytosis: Further supporting this concept, an elegant study of HSC development combining scRNA-seq with single-cell ATAC-seq, reported during the preparation of this manuscript, identified a population of putative precursors to HE characterized by high expression of arterial genes such as Sox17 and Hey2, in which multiple hematopoietic stem and progenitor cell-associated transcriptional programs appear to converge to regulate Runx1 expression21.