Fig. 1.

Three strategies to select the tissue-specific methylation signatures. Illustration of the tissue comparisons in the one-tissue-vs.-the-rest strategy (A), the one-group-vs.-another-group strategy (B) following the tissue development phylogeny (C), and the one-tissue-vs.-another-tissue strategy (D). The fragment-level methylation in a genomic region was compared between the negative group and the positive group. The phylogenetic tree (C) constructed was based on early tissue development (23). The first layer corresponded to the three germ layers in early embryo development. The second layer corresponded to the function systems. The third layer contained the 29 tissue types in our deconvolution model.