HSCs emerge from hemogenic endothelium in cbfb^−/− embryos. Expression of the HSC markers c-myb and runx1 in cbfb^−/− and WT embryos at 36 hpf by WISH. Compared with WT siblings (A-A′), the HSC marker c-myb was normally expressed in the hemogenic endothelium of the ventral DA of cbfb^del4/del4 (B-B′) and cbfb^ins4/ins4 (C-C′) embryos at 36 hpf. Similarly, the expression of runx1, another HSC marker, was also unaffected in cbfb^del4/del4 (E-E′) and cbfb^ins4/ins4 (F-F′) embryos, as compared with WT embryos (D-D′). Panels A′-F′ depict the boxed regions in panels A-F.