Flt3 fate-mapping reveals that the majority of GMPs and their mature progeny are derived from Flt3-expressing progenitors. (A) FACS analysis of eYFP expression in preGMPs (Lin⁻Kit⁺Sca-1⁻CD41⁻CD150⁻FcγR⁻CD105^low) and GMPs (Lin⁻Kit⁺Sca-1⁻CD41⁻CD150⁻FcγR⁺) in BM of Flt3::Cre//R26R-eYFP mice. Histogram shows percentage of preGMPs and GMPs expressing eYFP. Percentages are the means of 3 mice, analyzed at 10 weeks of age. (B) Representative FACS profiles of mature (Mac-1⁺Gr-1^neg-lo and Mac-1⁺Gr-1^hi) myeloid cells in the BM of Flt3::Cre//R26R-eYFP mice. Histogram shows percentage of Mac-1⁺Gr-1^neg-lo and Mac-1⁺Gr-1^hi cells expressing eYFP. Percentages are the means of 3 mice, analyzed at 10 weeks of age.