Epigenetic Mechanisms (IMAGE) Deutsches Zentrum fuer Diabetesforschung DZD Caption The direct methylation of the DNA permanently changes the gene expression when it occurs in control regions of genes (so-called CpG islets) made accessible by the modification of the histones. Credit © DIfE Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.