There are various similarities between euchromatin and heterochromatin. They are both forms of chromatin present in the nucleus. Heterochromatin tends to be more condensed and localized near the nuclear periphery or around the nucleolus, while euchromatin is less condensed and more dispersed throughout the nucleus. Both heterochromatin and euchromatin are composed of a combination of DNA and proteins. These proteins include histones, as well as non-histone proteins. Both euchromatin and heterochromatin consist of DNA molecules that are composed of polynucleotide chains, however, they serve different purposes. Euchromatin and heterochromatin are both organized and compacted into chromosomes through the primary nucleosome assembly. Additionally, during interphase both euchromatin and heterochromatin are visible within the nucleus of the cell.