Environmental Influence of Epigenetics

The epigenetics of an individual is in part built through an intrinsic program, such as an inherited template, and in part built by inputs of the environment. The latter improvises or in some cases permanently changes, the performance of genes from their normal course leads to structural or functional alterations. The influence of the environment is not limited to the contemporary stages; many may be traced before birth or transgenerational to their parental or ancestral time. This chapter reviews the environment, which have been found to influence the epigenetics to cast their actions. The exerting environment is divided here into mental or physiological environment, including enriched environment, learning experience, stress, etc., and the hazardous or chemical environment, including heavy metals, prescription drugs, and addictive substances. This review focuses on the links between the environment and its effect on various elements of epigenetics, and their influence on gene transcription.