Fig. 2

Methylation profiling of CP subtypes. The scatterplot (a) shows samples projected onto the first two principle components derived by applying PCA to the most variable 10,000 probes already selected for the clustering. Pediatric CP are marked with white circles and adult CP with black circles. Unsupervised consensus clustering of 450 k methylation data revealed two distinct and stable clusters corresponding to papCP and adaCP, respectively. The upper part of the figure shows the consensus matrix (brown) that displays the stability of the clusters, i.e. in all of the 1, 000 resampling iterations of the consensus clustering the same samples were assigned to the same two clusters (b). The lower part of the figure shows a heatmap of the methylation pattern of the 10,000 most variable CpG sites used for clustering. Below the heatmap the two clusters resulting from the consensus clustering of gene expression data is shown. Furthermore, the distribution of age, BRAF and CTNNB1 mutations across samples was added. The sample marked with a red dot represents a case with histologically unsure subtype classification