Figure 2

Principal Component Analysis. The plot shows a Principal Component Analysis (PCA) made on the gene expression profiles of 79 samples (dots). The x- and y-axis represent the first two principal components, PC1 and PC2 respectively, which together explain about 31.6% of the total variance. In each panel samples for each histotype are highlighted by different colors (HB: red dots; NB: blue dots; RMS: purple dots; WT: green dots). Samples coming from the same case are encircled and stars represent their center, whereas big black dots represent the center of the histotype. Grey dots represent samples of the other histotypes.