Cbfβ-SMMHC hinders B lineage–specifying transcriptional programs. (A) Relative expression levels of B lineage–specifying factor transcripts Sfpi-1, Il7r, Ebf1, Tcfe2a, Pax5, and Flt3 in control or Cbfβ-SMMHC restored CLPs analyzed by qRT-PCR. Shown are means plus or minus SD (n = 3; ***P < .001) from 3 to 5 independent sorting experiments, each performed by duplicate. (B) Percentage of cells retaining the restored Cbfb-MYH11 alleles analyzed by qPCR. Cells were transduced with MIG (□; 26% GFP⁺), Ebf1 (■; 34% GFP⁺) or E47 (▩; 24% GFP⁺) and differentiated on OP9-MIGR1 stromal cells over a period of 4 days. Shown are the representative means plus or minus SD data of 2 independent experiments, each performed in duplicate.