Figure 1

Tissue-specific methylation at specific LINE-1 loci (from morphologically normal tissue). (A) Heat map of methylation means at different LINE-1 loci in all tissues and in blood as measured by bisulfite pyrosequencing. The variances of mean methylation for males and females, across the studied tissues, are shown on the left and right of the graph, respectively. Global LINE-1 methylation values are given at the last two rows of the heat map (in black frame). The numbers of samples are shown under the tissue denomination. (B) Principle component analysis of methylation at all specific LINE-1 loci demonstrating identification of several separate tissues entities (ANOVA p = 0.0107 for males and p = 0.0031 for females; at a false discovery rate of 5%). The numbers of samples are shown to the left. (C) Hierarchical clustering of the individual methylation values for all samples. Ba: bladder; Bl: blood; Co: colon; F: female; M: male, Pa: pancreas; Pr: prostate; St: stomach; Var.: variance.