Before revision:  Looking at the ChAS of these epigenomic features in the interaction networks, we find Polycomb Group proteins and associated histone marks to be the most assortative factors . Remarkably,  we observe higher ChAS of the actively elongating form of RNA Polymerase 2 compared to the inactive forms in interactions between promoters and other distal elements, suggesting an important role for active elongation in promoter-enhancer contacts. CONCLUSIONS: Our method can be used to compare the association of epigenomic features to different type of genomic contacts. Furthermore, it facilitates the comparison of any number of chromatin interaction datasets in the context of the corresponding epigenomic landscape .
After revision:  Looking at the ChAS of these epigenomic features in the interaction networks, we find Polycomb Group proteins and associated histone marks to be the most assortative factors . Remarkably, we observe higher ChAS of the actively elongating form of RNA Polymerase 2 compared to the inactive forms in interactions between promoters and other elements. Conclusions: Contacts amongst promoters and between promoters and other elements have different characteristic epigenomic features. Using ChAs we identify a possible role of the elongating form of RNAPII in enhancer activity. Our approach facilitates the study of multiple genome-wide epigenomic profiles, considering network topology and allowing for the comparison of any number of chromatin interaction datasets in the context of the corresponding epigenomic landscape .