In eukaryotic cells, histones are essential for chromatin conformation and transcriptional regulation. The histone octamer is composed of two copies each of four histone proteins (H2A, H2B, H3, and H4). N-terminal tails of histone proteins are targeted to many types of modifications such as methylation and acetylation. Histone modifications are implicated in regulating the chromatin structure and transcription in eukaryotic cells. Recent studies have provided genome-wide histone modification data in human by using ChIP-seq method. Here we developed a novel method to detect histone modification patterns from ChIP-seq data. We used O/E (Observation / Expectation) value based method and P-value based method. We selected top 100 modification patterns that had high value of each method. And we used clustering method to selected modification patterns. Our methods detected candidates of functional histone modification patterns. And our result showed a tendency that DNA of “Full modified” nucleosome are hyper methylated.

Keywords: Epigenetics, Histone modification, DNA methylation, Computational analysis, Genome-wide analysis