The purpose of the present invention is to provide a composition for controlling a chromatin structure. A composition of the present invention contains: (1) a polymer which is selected from the group consisting of amphoteric polymers, anionic polymers and nonionic polymers having a specific main chain skeleton； or (2) a carrier which encloses two or more kinds of substances selected from the group consisting of expression vectors containing a gene such as a gene encoding histone acetyltransferase and inhibitors such as histone acetylation inhibitors.
