Epigenetics Worksheet

1. Often, the physical characteristics of genetically identical twins become increasingly
different as they age, even at the molecular level. Explain why this is so. (use the
terms "environment" and "epigenome")

Well, even though their genetics are the same, there epigenome isn't.  Since the epigenome is always changing, their life experiences may change their personality, appearance, or interests. This may explain the change through identical twins.

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

One of them is stress, sending different chemicals through the brain and can change the epigenome. Another is diet, in which thought can either become stronger or weaker. A third one is drugs, in which different chemicals can either strengthen current emotions or make them deactivate. Methyl will make a rat change from calm to anxious.

3. What is an imprinted gene?

An imprinted gene is a gene that is contributed to offspring by a parent. It's a gene that made it through mitosis and is now shaping up in a chromosome. This gene can be passed through many generations.


4: Discuss factors in your daily life (ie. Diet, exercise, stress etc.) that could be affecting
your epigenome

All the emotions listed on the question above do have a large impact on my epigenome. Diet may want you to eat healthier. Exercise may want you to train harder. Stress could make you learn more from life. These all have different answer, but it has a large impact on it. Take exercise for instance. Exercise makes your body fitter and you healthier. But, genetically it can add more or less chemicals that interact within your brain. Things start popping up, such as "should I train even harder or more often"? These things change your epigenetics mentally.



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

A high-nuturing mother will lick her pups constantly, making the GR gene much more active. If this occurs, there is a much quicker calm down if the brain is experiencing stress. If there is low nurturing, then the rat will have a harder to deal with stress.

6. In rats, does licking by the mother activate, or deactivate her pup's GR gene?

It activates it, crating a much calmer rat. When the GR protein is released into the hippocampus, there is a release of chemical cortisol. Since cortisol combines with GR protein, the combination sends out calming signals throughout the brain, making it easier or harder to calm down.

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

As said above, the combination of cortisol and GR create a calming signal throughout the brain. Since the protein is much more widely created if there is more nurturing in younger life, then more GP is created. This is exactly the opposite for low nurturing. So, when the cortisol is emptied into the hippocampus, the more GP proteins have a greater chance of attaching to one. More combinations will create a much stronger signal.

8. 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.

As said in the rat example the environmental traits can be inherited through a family. At my guess, this would be the same for humans. Epigenetics can be inherited to an organism, so I bet these environmental emotions would do the same. Because of the stress that can be interned from epigenetics, this stress, or diet, or any inheritable emotion. Now on its own, a human that is pregnant may have some type of diet that will affect her baby's epigenetics. When this baby grows up and has his/her own children, there is a very good chance that the diet may be passed on towards the next generation. Soon, there would be a group of people with that same epigenetic relationship. An organism can affect a large amount of people. Take this into consideration. If an organism has two children, and those children have to children, (etc.) there is a large amount of children with this "diet"
Diagram:
| <-- Person with epigenetic
|| <-- Children with passed on epigenetic
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etc.
From this diagram, there is a huge impact that this could have throughout a family tree.


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

Diet is very easily expressed through the epigenome. All food includes some type of ingredient, some healthy, some not. The healthy part doesn't matter, but genetically, there are chemicals that can change your personality. Specifically methyl can be extracted from food and put into the epigenetic chain. This can bring up the amount of activity in the epigenetic level.

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

Yes, scientists have studied this and have proven that pregnant mothers that don't eat enough nutrients can affect their child's outcome. Since methyl comes from the nutrients in food, under-eating can actually make the child's epigenetics low on methyl for life.


11. How does Dietary methyl influence gene expression ?

Methyl can be used to change epigenetic patterns. A rat can become from a calm attitude into an anxious one through the injection of methyl. This can happen with a lot of stress related epigenetic patterns.

12. Why do Toxins affect gene methylation?

Gene methylation can balance gene expression, but it has good use for long term memory of the epigenetics. I'm not entirely sure on this, but I believe that the toxins may actually reduce the amount methyl going towards the gene. This, in turn, may actually create a shorter memory through epigenetics. So these epigenetic patterns will not last as long.