Validation of the prognostic significance of the subgroups in the test set for bone marrow CD34⁺ cell samples. (A) Heatmap showing expression levels of 68 genes in the regression model for 100 patients with bone marrow CD34⁺ cell samples. Each row represents 1 gene, and each column represents 1 sample. Gene expression–based subgroups, WHO subtypes, and patients’ prognosis are shown below the heatmap. (B) A heatmap shows expression levels of 68 genes in the regression model for an independent cohort of 183 patients with MDS. (C) Rates of overall survival in the 2 subgroups for the test set of bone marrow CD34⁺ cell samples. (D) Cumulative incidence of leukemic transformation in the 2 subgroups for the test cohort of bone marrow CD34⁺ cell samples.