Epigenetics

1. The field of epigenetics is quickly growing and with it the understanding that both the environment and individual lifestyle can also directly interact with the genome to influence epigenetic change. These changes may be reflected at various stages throughout a person’s life and even in later generations.
2. For example, human epidemiological studies have provided evidence that prenatal and early postnatal environmental factors influence the adult risk of developing various chronic diseases and behavioral disorders.
3. Studies have shown that children born during the period of the Dutch famine from 1944-1945 have increased rates of coronary heart disease and obesity after maternal exposure to famine during early pregnancy compared to those not exposed to famine.

 Epigenetic Inheritance

1. It may be possible to pass down epigenetic changes to future generations if the changes occur in sperm or egg cells. Most epigenetic changes that occur in sperm and egg cells get erased when the two combine to form a fertilized egg, in a process called “reprogramming.” This reprogramming allows the cells of the fetus to "start from scratch" and make their own epigenetic changes.
2. But scientists think some of the epigenetic changes in parents' sperm and egg cells may avoid the reprogramming process, and make it through to the next generation. If this is true, things like the food a person eats before they conceive could affect their future child. However, this has not been proven in people.

 Epigenetics and Cancer

1. Scientists now think epigentics can play some role is the development of some cancer. For instance, an epigenetic change that silences a tumor suppressor gene — such as a gene that keeps the growth of the cell in check — could lead to uncontrolled cellular growth. Another example might be an epigenetic change that "turns off" genes that help repair damaged DNA, leading to an increase in DNA damage, which in turn, increases cancer risk.