Principal component analysis. In this supervised analysis each patient (n = 48) is represented by a colored sphere. Ellipsoids are drawn with 2-fold standard deviations. (A) The gene expression signature is given for the top 400 probe sets differentially expressed between 32 AML cases without MLD and 16 AML cases displaying MLD. (B) The same signature is now annotated according to known FLT3 mutation status of the cases. (C) The gene expression signature is given for the top 400 probe sets differentially expressed between 40 NPM1-mutated and 8 NPM1 wild-type AML cases. All 8 cases with NPM1 wild-type AML displayed MLD. Detailed information on the probe sets is available online.