Epigenome

IDENTICAL TWINS: PINPOINTING ENVIRONMENTAL IMPACT ON THE
EPIGENOME

1. Often, the physical characteristics of genetically identical twins become increasingly
different as they age, even at the molecular level.

1a. The appearance changes because of environmental factors that change the epigenome, although the genome stays the same. Diet for example is a factor that could change twin genomes. Exposure to toxins and stress are also contributors to the changes in the epigenomes.

2. Name 3-4 environmental factors that influence the epigenome.

2a. Diet, Exposure to toxins and stress.

3. What is an imprinted gene?

3a. A chromosome that has epigenetic tags that remained on after fertilization.

YOUR ENVIRONMENT, YOUR EPIGENOME

1. Discuss factors in your daily life (ie. Diet, exercise, stress etc.) that could be affecting
your epigenome. My excerise level isn't very high, so that is definitely affecting my epigenome. Diet and stress are also big factors, because

LICK YOUR RATS

1. Explain how a high-nurturing mother rat shapes her pup's epigenome, and what that
pup's response to stress will be.

1a. A high-nurturuing rat mother shapes her pup's epigenome by licking, grooming and nursing them. A high nurtured pup will become a calm adults, while low nurtured pups usually grow up to be anxious.

2. Explain how cortisol and the GR protein work together in the brain to relax a rat pup.
You may draw a diagram.

2a. The cortisol binds with the GR inside the hippocampus, and the bonds cause the hippocampus to send out signals that turn off the stress circuit, turning off adrenaline and cortisol production.

3. The rat nurturing example shows us how parental behavior can shape the behavior of
their offspring on a biochemical level. Relate this to humans and think about the personal
and social implications. Record your thoughts.

3a. With the ability to shape the behavior of offspring, I believe that child abuse and child neglect will become even higher offenses and the authorities will be on their toes for any people trying to hurt their children. People would also be more understanding of traits that aren't looked upon well by society. They would know that the reason they are acting a certain way is because of things parents did to affect the child's epigenome.

NUTRITION & THE EPIGENOME

1. Explain how the food we eat affects gene expression.

1a. Food affects gene expression in the way of methyl. When the diet of a pregnant mother's diet is rich in methyl, the offspring that results is normal and has a healthy life throughout. Mom's without a methyl rich diet produce offspring that don't really look like them, and the offspring tends to be obese and more prone to diseases like diabetes.

2. Can the diets of parents affect their offspring's epigenome?

2a. Yes. In the question above it is explained how methyl causes changes in embryos and postnatal offspring.

EPIGENETICS & THE HUMAN BRAIN

1. How does Dietary methyl influence gene expression ?

1a. Look at question 1 in NUTRITION AND THE EPIGENOME for the answer to this question.