DNA associated with hyperacetylated histone is preferentially digested by DNase I.

Butyrate-treated cells give rise to massive hyperacetylation of histones and have been used to test the idea that regions of DNA in association with hyperacetylated histones are preferentially solubilized upon digestion with DNase I. Such hyperacetylated histones can be derived from both pre-existing histones or from histone newly synthesized in the presence of butyrate which leads to extreme modification. The DNA in association with both types of hypermodified histone is equally and selectively digested.