Relative expression of selected genes of the minimum subset of 35 genes to NAM. The genes are arranged into clusters according to their capabilities as classifiers (VHL vs. all, SDHD-HN vs. all, SDHD-AT vs. all, NAM vs. all). Overlapping indicates that the respective genes show characteristic expression in two of the tumor groups. Overall significance has been evaluated for each gene by ANOVA (value given for each gene in the upper left corner). Significant differences between each group and (a) NAM, (b) SDHB, (c) SDHD-AT, (d) SDHD-HN, and (e) VHL are indicated above each applicable column. Replications of the letter specify the level of significance (xxx, P < .001; xx, P < .01; x, P < .05).