The leukemia cells were CD11b/Gr1-double positive (Fig. 3c), and expressed posterior Hox genes, including Hoxa6, Hoxa7, Hoxa9, Hoxa10, and Hoxa11, and several other genes including Meis1, c-Kit, and Myc, which were commonly observed in AML cells induced by MLL-mAf4 and other MLL fusions (i.e., MLL-ENL) (Fig. 3d)10,11,17. Here, HOXA6 is linked to leukemia.