Definitive hematopoietic potential is restricted to distal-GFP⁺ population. (A) Number of definitive (top) and primitive erythroid (EryP, bottom) colonies generated in methylcellulose by GFP⁺ and GFP⁻ cells FACS sorted from E8.5 distal-GFP HET embryos. Error bars indicate SD of the mean (n = 3). (B) Pictures of EryP colonies generated from GFP⁺ and GFP⁻ cells sorted from E8.5 embryos. (C) Number of colonies generated by distal-GFP⁺, distal-GFP⁻, and not sorted (pre) cells from E9.5 (top) and E10.5 (bottom) yolk sac (YS) and embryo proper (embryo). (D) Pictures of OP9 cocultures of distal-GFP⁺ and distal-GFP⁻ cells sorted from E10.5 yolk sac (YS) and embryo proper (embryo), taken 4 days after the sort. (E) FACS analysis of Mac1 and CD19 expression in OP9 cocultures from distal-GFP⁺ cells taken 8 days after the sort. (F) FACS analysis of CD4 and CD8 expression in OP9-DL1 cocultures from distal-GFP⁺ cells, taken 13 days after the sort. Numbers indicate percentages of respective populations.