Pie chart illustrating the molecular heterogeneity of cytogenetically normal AML based on mutations in the NPM1, CEBPA, MLL, FLT3 (ITD and TKD mutations at codons D835 and I836), NRAS, and WT1 genes. The bluish colors denote NPM1-mutated subsets, the orange/red colors CEBPA-mutated subsets, and the yellow/green colors MLL-mutated subsets. The gray colors depict subsets without hypothetical class II mutations, and the white sector shows the subset without any mutation in the above-mentioned genes. Data are derived from mutational analysis of 485 younger adult patients with cytogenetically normal AML from AMLSG.