近年來，表觀基因體學的文獻發表有成長的趨勢，許多的文獻都著重於表觀基因體與影響基因的表現狀況。此篇論文，我們則提出了與以往不同的角度來分析表觀基因體與脫氧核醣核酸酶I高敏感位點之關聯性。
於組蛋白修飾的部分，我們能從文獻中得知，某些組蛋白修飾會引起基因高表現或低表現。此次我們的研究在脫氧核醣核酸酶I高敏感位點與六種組蛋白修飾中，我們觀察到這六種組蛋白修飾與open chromatin有相關性。例如：從脫氧核醣核酸酶I高敏感位點與H3K4me3共同存在的頻率會比脫氧核醣核酸酶I高敏感位點與H3K27me3共同存在的頻率還要高。H3K4me3與open chromatin有正相關；反之，H3K27me3則與open chromatin呈負相關性。
另外，我們也分析在不同細胞株的H3K4me3與H3K27me3共同調控的基因中，他們各自的功能，此結果與之前文獻亦有相同之處。例如：癌症細胞中，我們發現與代謝相關基因，它們存在於H3K4me3與H3K27me3重疊的地方。

In recent years, publications of papers on epigenetics have increased. Many papers concerned epigenetics and gene expression. This thesis analyzed the association between epigenetics and DNase I hypersensitive sites.
We focus on histone modification part of epigenetics. Previous studies indicated that some histone modifications might affect gene expression. This thesis analyzed the association between six types of histone modifications and DNase I hypersensitive sites, and we found correlations between histone modifications and open chromatin. Specifically, From our research, H3K4me3 and DNase I Hypersensitive sites overlap more frequently then H3K27me3 and DNase I Hypersensitive sites frequency. H3K4me3 is positively correlated with open chromatin, and H3K27me3 is negatively correlated with open chromatin.
Besides, we also analyzed, across cell lines, the functions of genes where H3K4me3 and H3K27me3 overlap, and the result is similar to the previous studies. For example, in cancer cells are found metabolism-related genes with overlapping H3K4me3 and H3K27me3.

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