Epigenetic processes can explain some of the epidemiological associations between environmental exposure and disease, particularly when the exposure occurs at a critical delopmental stage.Epigenetics, a cellular mechanism once considered to be stable after development, has now been found to be a dynamic process that occurs in fully differentiated, post-mitotic cells of central nervous system in response to environmental signals. Epigenetic mechanisms regulate the structure of the chromatin through post-translational modifications of histone proteins and covalent DNA modifications. Though the mechanisms through which these effects are achieved likely involve diverse cellular and molecular pathways, there is emerging evidence supporting the hypothesis that epigenetic changes, such as DNA methylation and histone modifications, may mediate the effects of early-life variations in the social interactions between mothers and infants.
