MUC4 and acute myeloid leukemia: Scl-CreERT:FLT3ITD/ITD AML had only two somatic mutations, in the genes Muc4 and Arcn1, with low variant allele frequency (VAF 0.075 and 0.155, respectively), whereas FLT3ITD/ITD controls had a sole mutation in Vmn2r89 (low VAF, 0.039) (Fig. 4D; Supplementary Table 2).