Correlation between CpG island methylation and gene expression. (A) Heatmap and PCA showing the most significantly hypermethylated genes in t(4;11)-positive infant ALL (red dots) compared with normal bone marrows (blue dots). Relative DNA methylation levels are shown in red (high) and blue (low). (B) Heatmap and PCA showing the corresponding gene expression levels from the same genes and samples as presented in panel A. Relative gene expression values are shown in red (high) and green (low). Similarly, the (C) CpG methylation data and (D) gene expression data are presented for t(11;19)-positive infant ALL samples (orange dots) compared with normal bone marrow (blue dots).