process amplifies epigenetic marks and counters the dilutive effect of nucleosome duplication.

However, for small domains approaching the size of individual genes, old nucleosomes are spread too thinly for accurate propagation of histone modifications. In these regions, chromatin structure is probably controlled by incorporation of histone variants during nucleosome reassembly. The close correlation seen between H3.3/H2A.Z and transcriptionally active regions lends support to this proposed mechanism. Unfortunately, a causal relationship