Reconstitution of hematopoietic stem and progenitor cells >16 weeks in Mpl^−/−mice transplanted with Mpl^−/−BM transduced to express 1 of the selected genes. (A) Contribution of donor cells (CD45.2⁺) on LSK cells (mean plus or minus SD; 2-tailed, unpaired Student t test with Welch correction [*P = .024]; compared with the negative control). (B) Contribution of LSK cells in the nucleated BM cells (mean plus or minus SD; 2-tailed, unpaired Student t test with Welch correction [**P = .001]; compared with the negative control). (C) Representative flow cytometric analysis of LSK cells on the expression of CD34 and CD135 to discriminate between LT-HSCs, ST-HSCs, and MPP, as indicated, from mice of the gene groups Epcr and Hoxa10 compared with the negative and positive controls. (D) Contribution of MPP, ST-HSCs, and LT-HSCs on the LSK cells of the different gene groups (positive control, n = 10; negative control, n = 9; Pbx1, n = 7; Epcr, n = 6; Hoxa10 and Mycn, n = 3; mean plus or minus SD; Student t test with Welch correction [*P ≤ .05; **P ≤ .01]) (2-way ANOVA [P = .07]; Epcr vs negative control). (E) Number of total MPP, (F) ST-HSCs, and (G) LT-HSCs per mouse in the different gene groups. (E-G) Positive control, n = 10; negative control, n = 9; Pbx1, n = 7; Epcr, n = 6; Hoxa10 and Mycn, n = 3; mean plus or minus SD; 1-way ANOVA with Dunnett multiple comparisons test; Epcr vs negative control LT-HSCs (##P = .0037 [Student t test; P = .08]).