,6,7 Using hPSCs, we demonstrated that SOX17 is a master regulator of HOXA and arterial programs in HE, and is required for the specification of HE with robust lympho-myeloid potential and DLL4+CXCR4+ phenotype resembling arterial HE at sites of HSC emergence.13 Here, CXCR4 is linked to hereditary elliptocytosis.