Define behavioral epigenetics and give two examples of research that has shown how epigenetics functions in humans.

Question

What will be an ideal response?

Answer 1

Ans: The study of the chemical reactions that activate and deactivate parts of the genetic material of an organism, as well as the factors that influence these chemical reactions. Behavioral epigenetics has been described as the bridge between nature and nurture. One example of how behavioral epigenetics works has been demonstrated by Michael Meaney, a researcher at McGill University, who studied rat mothers and their offspring. He and his colleagues found that rat babies reared by mothers who ignored them and did not touch them were more fearful and stressed by environmental events later in their lives, shown both by the babies’ behavior and by the levels of stress hormones they produced. These researchers were able to link this behavior with a particular gene that was active in babies reared by nurturing mothers but which had been “turned off” in the neglected babies. Turecki and Meaney (2016) reviewed 40 studies (13 animal studies and 27 human studies) on the relation between early stress and later epigenetic markers in children’s genomes. The human studies examined a history of trauma in early childhood, including child abuse and parental death. They found strong evidence for the effect of early stress on changes in the epigenome, which consists of all the chemical tags that can turn genes on and off, in parts of the brain that control reactions to stress. Individuals with these changes are more reactive even to lower levels of stress and more prone to depression and anxiety as a result.