Menin and MLL1 regulate common and distinct genes during B lymphopoiesis. (A) Schematic diagram showing B-cell differentiation using the Hardy fractionation scheme and nomenclature.³⁶  Below each population is shown the YFP⁺ percentage (thus the penetrance of cre excision) determined using Rag1-cre;RosaYFP reporter animals (Gan et al, in preparation), n = 3-4 animals per population. Fraction B (gray) cells were used for the microarray analyses. (B) Pie chart showing the proportions of differentially expressed probe sets in Men1-deficient vs wild-type fraction B cells. Differentially expressed probe sets were determined as described in the “Methods” section. (C) Pie chart showing the proportions of differentially expressed probe sets in Mll1-deficient vs wild-type fraction B cells. Data are from Gan et al (in preparation) and were analyzed with the same criteria as in panel B. Each group was compared against its own wild-type littermate controls. (D) Pie chart showing the number of probe sets in common between the 2 sets of differentially expressed (down- or upregulated) probe sets in the analyses shown in panels B-C. For details, see supplemental Figure 6.