Infant ALL subtype-specific CpG island hypermethylation. (Ai-ii) Heatmaps showing the 20 most significantly hypermethylated probes for each infant ALL subtype. Columns represent patient samples and rows represent genes. Relative DNA methylation levels are shown in red (high) and blue (low). Genes and samples were ordered by the use of hierarchical cluster analysis (Euclidean distance, complete linkage), and gene identifiers are listed at the right. (Bi-ii) PCAs separating t(4;11) (red), t(11;19) (orange), t(9;11) (yellow), and MLL wild-type infant ALL (green). (Ci-ii) shows the PCA when normal pediatric bone marrow samples (blue) are included in the analysis. (Ai, Bi, and Ci) Data from the custom 9K CpG island microarray. (Aii, Bii, and Cii) Data from the commercially available 244K CpG island microarray (Agilent).