epigenetic

Definition of epigenetics
National Cancer Institute

epigenetics

(EH-pih-jeh-NEH-tix)
The study of how age and exposure to environmental factors, such as diet, exercise, drugs, and chemicals, may cause changes in the way genes are switched on and off without changing the actual DNA sequence. These changes can affect a person’s risk of disease and may be passed from parents to their children.

Source: NCI Dictionary of Cancer Terms