Figure 4. Characterization of Hallmark of Aging predictivity within the aging phases. (A) Hierarchical clustering of the nine Hallmarks of Aging based on their gene set predictivity analysis along the four aging phases. Predictivity was determined using cross-validated random forest classifiers, trained to distinguish each of the aging phases from the others. (B) Predictivity of the Hallmark of Aging gene sets along the four aging phases, grouped into primary, secondary and integrative hallmarks. Statistical testing was performed using one-sided Wilcoxon tests. All predictivity scores were derived from 100 permutations.