Interestingly, mixed states of PRC occupancy and DNA methylation have been found in somatic and cancer cells: loci with overlapping H3K27me3 and methylated DNA have been described [54, 60, 61] and genes that are enriched for H3K27me3 in normal cells can display H3K27me3 and DNA methylation or DNA methylation only in cancer cell lines of the same tissue [54, 62]. The gene discussed is PPRC1; the disease is cancer.