Fig. 6. Comparison of haematopoietic development from differentiating Mixl1 (w/w), heterozygote (GFP/w) and null (GFP/GFP) ES cells. (A) Flow cytometric analysis of day 6 EBs showing Mixl1-deficient cells failed to efficiently generate TER119-positive erythroid precursors despite their ability to form significant numbers of CD34-positive cells. (B) Summary of methylcellulose culture experiments (n=3) indicating that Mixl1-deficient day 4 EBs contained significantly fewer blast colony-forming cells (BL-CFCs) and primitive erythroid precursors (EryP). Data were derived from experiments performed with two independent Mixl1-deficient ES cell lines and their wild-type and heterozygote counterparts. The Mixl1-null lines M916 and M3C5 were derived from Mixl1-heterozygous ES cell lines M147 and M114 respectively. Mixl1^w/w is the parental ES cell line. The error bars represent 1 s.d. and the P values indicated were derived using a two-tailed t-test. GF, growth factors (VEGF, SCF, IL3, EPO). No EryP colonies were seen in the absence of growth factors (-GF).