Hierarchical clustering to separate ALL subtypes by methylation profiles. Unsupervised hierarchical clustering was performed by the use of beta values for the 300 selected CpG sites as the distance metric and average linkage as the clustering method, including all study samples. In the dendrogram each individual sample is represented by a horizontal line, and the color of the line corresponds to the cytogenetic subtype of the sample. The color code for the ALL subtypes is given above the dendrogram. The CpG sites are clustered according to methylation level and shown in the vertical columns. High methylation levels are shown in red and low methylation levels in blue, according to the scale bar below the figure.