Heat map of the gene-expression signature associated with ASXL1 mutations in older patients with primary CN-AML. Differential gene expression was studied within the subset of NPM1-wt/FLT3-ITD-negative patients, to avoid confounding by those gene mutations. In this subset, a comparison of ASXL1-mut (n = 26) and ASXL1-wt (n = 39) patients identified 92 differentially expressed probe sets. The heat map shows expression levels of these 92 probe sets in all 185 older CN-AML patients with available microarray data. The NPM1-wt/FLT3-ITD-negative subset where the signature was derived is indicated by the gray bar at the bottom of the heat map. Rows represent probe sets; and columns, individual patients. Patients are grouped by ASXL1 mutation status, and genes are ordered by hierarchical cluster analysis. Expression values of the probe sets are represented by color: blue represents expression less than the median value for the given probe set; and red, expression greater than the median value for the given probe set. Arrows identify genes that are discussed in the text, with the vertical bar indicating multiple probe sets representing the same gene (CYP1B1).