Irf8−/− mice have reduced numbers of CDPs and increased numbers of GMPs. Progenitor cells in the BM of Irf8−/− and wild-type mice were analyzed by flow cytometry. Graphs show the frequency (left) and absolute number (right) of common myeloid progenitor (CMP), GMP, and CDP. Horizontal lines indicate the mean and error bars show SEM. Each data point represents one mouse, with data for 14 wild-type and 13 IRF8−/− shown; **P < .05.