Describe evidence from animal and human studies that environments influence gene expression. What types of conclusions can be drawn from these studies?

Question

What will be an ideal response?

Answer 1

The ideal answer should include:
1. Studies show that mother rats vary genetically in their tendency to lick and groom their offspring and engage in arched back nursing.
2. To determine whether differences in offspring behavior were due to genes or environment, the pups of nurturant mother rats were switched to the care of non-nurturant rats and vice versa (cross-fostering).
3. The results were that the type of mothering mattered more for the behavior of the pups than the genetic predispositions of the rats.
4. Studies of the baby rats' brains indicated that those raised by less nurturant mothers had reduced protein-making activity of genes controlling the brain's system for producing stress hormones.
5. One conclusion that can be drawn is that genetic expression can be modified by early experience. This means that the quality of the environment may have important implications for the offspring's behavior. In this case, environmental experience has the potential to modify the way that the brain functions, particularly in the management of the stress hormone response.