While healthy donor CD34+ cells, promyelocytes, neutrophils, monocytes, T cells, and B cells all had RUNX1/CBFB mRNA expression ratios of approximately 1:1 (Figure 8B, black dashed line; CD34+ ratio 1.2:1 ± 0.4), consistent with the 1:1 RUNX/CBFB required for CBF activity, all tested AML samples had elevated RUNX1/CBFB ratios (Figure 8B; red dashed line indicates AML mean ratio of 9.6:1 ± 4.8). Here, RUNX1 is linked to acute myeloid leukemia.