Distribution of NRAS mutations within morphologic subgroups. Significant differences compared with the total cohort are labeled with asterisks (*underrepresentation; **overrepresentation). AML subtypes: M0, 6 of 94 (6.4%); M1, 29 of 365 (7.9%); M2, 71 of 750 (9.5%); M3, 2 of 62 (3.2%); M3v, 0 of 32 (0%) (P = .058); M4, 34 of 343 (9.9%); M4eo, 39 of 116 (33.6%) (P < .001); M5a, 3 of 77 (4.2%); M5b, 9 of 81 (11.1%); M6, 7 of 84 (8.3%); M7, 0 of 8 (0%); n.a. (no subtype documented), 2 of 26 (7.7%); total, 203 of 2037 (10%).