Tuesday, December 14, 2010

Epigenetics and Environment

1. Often the physical characteristics of genetically identical twins become increasingly different as they age, even at a molecular level. Explain why this is so.

The environment a person in can influence their epigenome. The video spoke about how identical twins are very similar at birth, but then as their individual environment changes they become more unique. It showed how different the twins became from eachother. Different factors influencenced the twin's epigenome. The twins unique habbits further differentiated them. Specific habbits like smoking and exercising can especially affect the epigenome.

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

A major factor that would affect the epigenome would be smoking or even second hand smoke. Smoking has a very negative impact on the epigenome while something like excercising has a very positive impact on the epigenome. As you could imagine, food has a great deal of influence on your epigenome because you are putting it into your every day. The decisions you make when you eat have a very large impact on your epigenome. Other things that can have an impact on your epigenome are stress, your home life and even the people you are around.

3. What is an imprinting gene?

Imprinted genes are genes whos expressions were determined by their parent gene.

Discuss factors in your daily life that could be affecting your epigenome.

By far, the largest factor in my daily life that affects my epigenome is stress, specifically ones related to school. The huge ammounts of homework from a majority of my classes, the tests at the end of every week, the quizzes every day in my classes, and a project every week in DLC keeps my stress level extremely high. At home I have a relatively healthy diet. We rarely, if ever eat fast food or even eat out. The only time I eat unhealthily is at school because of the lunches they serve. I also have PE every day where I run a quarter mile every Monday, Tuesday and Thursday; run a mile every Wednesday; and run a half mile every Friday plus all the activities we do.

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.

One of the jobs in the hippocampus of the brain is to relieve stress. How the pup was nurtured affects how much GR is produced (more GR is better). Cortisol, a hormone put into the blood system durnig fight or flight, binds together with the GR to send calming signals to the pup. The more the rat is nurtured by its mother, the quicker it will be able to recover from stress.

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

The mother's licking will activate the pup's GR gene.

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

Refer to question number 1s answer.

4. 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.

Loving a child is like nurturing a rat. If a rat is nurtured and cared for, that can be the same thing as loving, praising, and teaching a child to do good in life. This shapes the way they will be when they are older. If the child had a good childhood, they will be nicer people but if not then they could turn out to be less kind.

Nutrition & The Epigenome

Explain how the food we eat affects gene expression.

"Familiar nutrients like folic acid, B vitamins and SAM-e [S-Adenosyl methionine, a popular over-the-counter supplement] are key components of this methyl-making pathway. Diets high in these methyl-donating nutrients can rapidly alter gene expression, especially during early development when the epigenome is first being established."

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

Yes, the food that a mother consumes when there is a baby in the womb is very important. Food eaten when a child in a womb helps deterine how well the baby will form. The way a grand mother or grandfather ate, even in the later years of their lives greatly shortens the lifespan of the grandchildren or even the great grandchildren. Foods eaten by mothers during pregnacy will most likely be appealing flavors, tastes and smells to the child. Mothers who drank or smoke during pregnacy have a greater chance of their child living under the influince of alcahol (alcoholism) and smoking.

Epigenetics & The Human Brain

1. How does Dietary methyl influence gene expression?

The Dietary Methyl influence gene is expression when you have a certain amount of methyl that your body will retain from the nutrients in your food. This food needs to be able to make you healthy. You have a significantly higher chance of becoming obese if you have a methyl-deficient diet.

Why do Toxins affect gene methylation?

The toxins affect the gene methylation by ruining your health. Different chemicals can have different affects. Take the chemical BPA for instance. BPA can cause endocrine problems like obesity, stunted growth, and birth defects.