First, advances in understanding “gene - environment interplay” help underscore how inseparable are the influences of genetics and environment. Contrary to traditional views that the efects of heredity are immutable and direct, contemporary studies of gene-environment interaction and epigenetics show that how heredity is expressed in behavior depends significantly on environmental influences. The most groundbreaking perspective comes from the emergent field of behavioral epigenetics, which shows that environmental conditions can alter gene expression— that is, whether genes become activated (and thus influential) or deactivated (and this uninfluential) in behavior and development. Thus even though DNA never changes, its expression can change. There is still much to be learned about epigenetic processes, but current research reviewed by the committee indicated that stress is one of the most potent environmental conditions provoking epigenetic changes in gene expression in childhood