MEIS1 and leukemia: We found that, although the MLL-r leukemia patient group as a whole presents with significantly higher average levels of MEIS1 mRNA compared to MLL-wt leukemia patients, MEIS1 mRNA expression levels vary within the MLL-r leukemia patient subset, and for some patients are within the ranges found for MLL-wt leukemia patients, reflecting our findings in MLL-r leukemia cell lines (Fig. 6d).