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.
After revision:  Based on 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.