The EpiMark® Nucleosome Assembly Kit is used to make unmodified recombinant human nucleosomes with user-supplied DNA or the provided control DNA. Purified recombinant human Histone H2A/H2B Dimer and Histone H3.1/H4 Tetramer are mixed with DNA at 2 M NaCl. To generate nucleosomes, the salt concentration is lowered by dilution or dialysis allowing each histone tetramer to associate with two histone dimers and form the histone octamer on the DNA (1,2). A method for assaying nucleosome formation by gel shift assay is included. These nucleosomes may serve as better substrates for enzymes that are inactive on the DNA or one of the core histones alone (3,4). Each reaction creates nucleosomes from ~1 µg of 208 bp DNA and may be scaled depending on the experiment.