Methyl cluster gene suppression is associated with age. (A) A defined gene cluster (designated as “methyl cluster”) was revealed through hierarchical clustering of 146 primary ovarian cancers based on the expression of the 378 candidate methylated genes (454 probes). Expression is shown by green to red (low to high) coloration within the heatmap with age of the patient (below the heatmap) inversely correlated with expression. (B) The methyl cluster genes in panel A similarly stratified an independent set of 77 primary ovarian cancers, with lower gene expression again associated with increased age.