DNA methylation aberrations that are found only in Y- or T-iPSCs. A. Principal Component Analysis showing that methylomes of Y-iPSCs, T-iPSCs and ESCs segregate into separate groups. B. Volcano plots of all CpG sites analyzed. The beta value difference in DNA methylation between Y-iPSCs and T-iPSCs is plotted on the x-axis, and the p-value for a FDR-corrected Wilcoxon signed-rank test of differences between Y-iPSCs and T-iPSCs (shown on − log10 scale) is plotted on the y-axis. CpGs that are significantly different between the 2 subtypes are shown on the upper left corner (significantly hypermethylated in T-iPSCs) and upper right corner (significantly hypermethylated in Y-iPSCs). C. CpGs that are hypomethylated in fibroblasts but are aberrantly methylated in iPSCs. D. CpGs that are hypomethylated in fibroblasts but fail to acquire methylation in iPSCs. E. CpGs that are hypermethylated in fibroblasts but aberrantly demethylated. F. CpGs that hypermethylated in fibroblasts but aberrantly gets demethylated in iPSCs. G. Summary of the classes of DNA methylation aberrations found only in Y-iPSCs (left) or T-iPSCs (right) but not both.