CpG islands under selective pressure are enriched with H3K4me3, H3K27ac and H3K36me3 histone modifications.

In this paper, we have studied, using a computational biology approach, the relationship between histone modifications in CGIs and selective pressure in Homo sapiens. We considered three histone modifications: histone H3 lysine 4 trimethylation (H3K4me3), histone H3 lysine 27 acetylation (H3K27ac) and histone H3 lysine 36 trimethylation (H3K36me3), and we used the publicly available genomic-scale histone modification data of thirteen human cell lines. To define regions under selective pressure, we used three distinct signatures that mark selective events from different evolutionary periods. We found that CGIs under selective pressure showed significant enrichments for histone modifications.