Epigenetics
Please note that this section contains my personal notes from my readings on this topic.
I first heard about epigenetics on a Dr. Oz show discussing pregnancy myths. He says that this new field of science — epigenetics — is finding that what happens in the womb can influence which genes are turned on and off. From a PBS special on epigenetics:
“Epigenetics literally translates into just meaning “above the genome.” So if you would think, for example, of the genome as being like a computer, the hardware of a computer, the epigenome would be like the software that tells the computer when to work, how to work, and how much.”
– Randy Jirtle in Epigenetics on PBS (July 24, 2007)
“In fact, it’s the epigenome that tells our cells what sort of cells they should be. Skin? Hair? Heart? You see, all these cells have the same genes. But their epigenomes silence the unneeded ones to make cells different from one another. Epigenetic instructions pass on as cells divide, but they’re not necessarily permanent. Researchers think they can change, especially during critical periods like puberty or pregnancy.”
“Basically, what you eat can affect your future generations. So you’re not only what you eat, but potentially what your mother ate, and possibly even what your grandparents ate.”
– Randy Jirtle in Epigenetics on PBS (July 24, 2007)
“One of the main findings of our research is that epigenomes can change in function of what we eat, of what we smoke, of what we drink. And this is one of the key differences between epigenetics and genetics.”
– Manel Esteller in Epigenetics on PBS (July 24, 2007)
From the Dr. Oz website:
As DNA, the blueprint of your body, is rolled out during development, it gets copied. And while that copying occurs, the things you are experiencing – what you eat, the toxins you are exposed to – can stop that copy machine from working properly. This basic principal of epigenetics means that, while we can’t control what genes we pass on to our children, we may be able to control which genes get turned on or turned off.
…Here’s another example that will help you put epigenetics in perspective. We share 99.8 percent of the same DNA as a monkey, and any two babies share 99.9 percent of the same DNA. Heck, we even have 50 percent of the same DNA as a banana. So genes alone cannot explain the diversity in the way we look, act, behave, and develop. How those genes are expressed plays a huge role in how vastly different we are from monkeys and how explicitly and subtly different we are from each other.
What you can do:
- Staying fit and healthy during pregnancy may dramatically influence how your child’s genes function throughout life. Unfortunately, because 50% of pregnancies are unplanned, many women lose the opportunity to set a healthy stage for those early weeks of embryonic and fetal development. Even if you don’t have plans to get pregnant, you can take simple steps now to improve your health so that, if and when you do conceive, you give your future child the best start possible.
- Expecting moms should also limit their exposure to the following toxins.
- BPA. A chemical compound used to make hard plastics, BPA can be found in food containers, baby bottles, and the lining of cans, it may cause changes in the way hormones work in our bodies. Developing fetuses and young children are the most vulnerable to it. Four easy ways to reduce your exposure to BPA include breastfeeding to avoid using baby bottles, choosing BPA-free bottles when you do use them, not microwaving food in plastic containers (heat can cause BPA to be released), and limiting your use of canned foods.
- Mercury. Everyday in the US, over 600,000 babies are born with unsafe levels of mercury in their blood. The chemical element is associated with developmental delays, so it is important for pregnant women to steer clear. One of the easiest ways to do so is to limit your intake of tuna to less than 6 ounces per week.
- Radiation Ionizing. Radiation, such as that produced by X-rays and computed tomography (CT) scans can potentially harm a developing fetus, particularly in the early weeks of pregnancy. Though many diagnostic tests will not cause a problem, doctors usually try to limit exposure to unnecessary radiation during pregnancy or take important precautions, such as using a lead apron, during medically necessary scans.
CAN YOU CONTROL WHICH GENES YOUR CHILD WILL EXPRESS?
While you can’t control which genes you pass on to your child, you do have some influence over which genes are expressed, affecting what features are seen in your baby (his phenotype). In fact, what you eat, breathe, and even feel can affect the long-term health of your child.
Stressors in the mother’s environment cause a change in the gene expression patterns of the fetus. That means the chemicals your baby is exposed to in utero, via the foods you eat and the cigarettes you don’t inhale, serve as biological light switches in your baby’s development. On, off, on, off — you decide how your child’s genes are expressed, even as early as conception.
You don’t have total control. We still don’t know how you can change your baby’s eye color, or when his hair falls out. But we do know how to influence some really important factors like your child’s weight or intelligence. So there’s an important reason why we’re able to turn certain genes on and off. Our bodies have to adapt to a changing environment (that’s how a species survives, after all). But our ability to adapt would be much too slow if we had to wait generations for our genes to change through random mutation (the classical theory of evolution).
“We’ve got to get people thinking more about what they do. They have a responsibility for their epigenome. Their genome they inherit. But their epigenome, they potentially can alter, and particularly that of their children. And that brings in responsibility, but it also brings in hope. You’re not necessarily stuck with this. You can alter this.”
– Randy Jirtle in Epigenetics on PBS (July 24, 2007)
Sources:
(1) Dr. Oz website
(2) Epigenetics on NOVA scienceNOW, Aired on PBS July 24, 2007.
Related Content:
Click on The Power of Nutrition to read about how nutrition can influence gene expression.
{ 1 trackback }