Histones are essential for chromatin conformation and transcriptional regulation in eukaryotic cells. N-terminal tails of histone proteins are targeted to many types of modifications such as methylation, acetylation, phosphorylation and ubiquitination. Recent studies have provided genome-wide histone modification data in human by using ChIP-seq method. However, functions of histone modification patterns are largely unknown. In this study, we developed a novel method to detect modification patterns. To detect bivalent histone modification, we used relative O/E value that donated the difference between O/E values of bivalent modifications in target region and those in the whole genome region. We detected 5 bivalent histone modification candidates. Network analysis showed candidates were important node of modification network. This results support our candidate of bivalent histone modification pairs.

Keywords: Epigenetics, Histone modification, Computational analysis, Genome-wide analysis, Bivalent chromatin