Can Your Lifestyle Affect Your Unborn Child? (Part 2)

This is the second of two articles on the subject. If you haven't read the first part, read it here.

Last time, we talked about Lamarckism and epigenetics, which will now help us answer the original question.

First, let us refresh our memory really quickly.

Lamarckism: The idea that organisms can pass on characteristics that it has acquired throughout its life.

Epigenetics: Change in expression of the genetic material (DNA), rather than a change in the coding sequence. 

Now, we'll combine the two ideas to reveal something that was discovered relatively recently.

Epigenetic Lamarckism.

Sounds kind of cool, right? But what is it? As the name suggests, epigenetic Lamarckism is the idea that epigenetic patterns that govern the expression of genes can be passed on from parent to offspring. As the expression of genes is related to the events in an organism's life, the inheritance of epigenetic patterns can be termed Lamarckian. Sounds like a neat little hypothesis, but is there any evidence-based research that supports the suggested form of Lamarckian inheritance?

Well, while it has not yet been experimentally demonstrated in humans, there is some evidence from rodent models. For example, a 2010 study showed that male rats that were fed a high-fat diet were more likely to have obese female offspring. Another study, published in 2013 showed that mice that were trained to fear the scent of a chemical, produced offspring that were as likely to be scared by the same scent. A study on birds shows that the circadian rhythm (the body's internal time-keeping system) of a mother can be epigenetically inherited by their offspring. Creepy?

So, should you be concerned? While trans-generational epigenetic inheritance hasn't been observed in humans, based on the evidence from model studies, it would be reasonable to assume that our lifestyle choices (what we eat, when we sleep) may affect our unborn kids.

The good news is that epigenetic inheritance is what we might call soft inheritance, which means that it is unstable and might revert to normal expression once the stimulus inducing it has been eliminated. Unlike hard inheritance, where the gene undergoes a permanent change in the form of a mutation.

However, there is some evidence to suggest that the predisposition to certain diseases could be epigenetically inherited by offspring in humans. So, we'd rather be careful not to pass on our habits to our children by maintaining a relatively healthy lifestyle. Stay healthy. Keep your unborn kids healthy. And yes, give my post a like.

Until next time! Bubye!

Can Your Lifestyle Affect Your Unborn Child? (Part 1)

This is the first of two articles on the subject, the second article will be posted on or before the 10th of June, 2017. 

Darwin's theory of natural selection provided us with a beautiful explanation for all the life we see around us. But not many of us know that there were other competing theories, that were ostensibly eliminated through natural selection. 

One of the most interesting theories of the origin of species was proposed by Jean-Baptiste Lamarck, a French naturalist in 1809, almost half a decade before Darwin published his book 'On The Origin of Species'. Why then, couldn't Lamarckian theory survive the test of time? Well, while Lamarck may have been the first to suggest the theory of evolution, the process he described was very different from Darwin's gradualism. Lamarck's theory is what is now called the use-disuse theory. 

Simply, there are two ways to explain the long neck of a giraffe. A Lamarckian explanation would suggest that the ancestors of giraffes that stretched their necks to get to the foliage on higher trees would pass on the information to their unborn offspring, causing them to grow longer necks. While this does sound like a plausible theory, it would predict the appearance of newer forms of life in a much shorter span of time. That, as we know, is not the case. 

Why am I talking about hungry giraffes and theories of evolution? Am I not supposed to deal with the question in the title of this article? All in good time.

See, the crux of Lamarckism is that we are somehow able to pass on acquired characteristics to our offspring. For humans, this would imply that our lifestyle; the way we eat, sleep, etc would have an indirect effect on our future offspring. But considering that the theory has been abandoned, that's not true, right? Or, is it?

As mentioned in my previous article, genes work by encoding information which is then decoded by a pathway that is usually called the central dogma. Remember? DNA makes RNA makes Protein. Well, DNA does not literally make RNA (same for RNA and proteins), but you get the point. But if that's the case, and all the cells in our body have the same DNA, why doesn't your eyeball have hair? Any such questions can be answered with one word: Epigenetics.

If genes are our master puppeteers, epigenetics is what keeps those genes on a string. This is usually done by processes such as acetylation, methylation and differential condensation of the DNA and these processes may be interconnected in regulating the differential expression of these genes. These processes basically involve the addition of a methyl or acetyl (tiny molecules) tags that affect whether the DNA sequence is expressed as protein or not. 

Okay, you get that. But, what does it have to do with whether or not you can affect your unborn child with your lifestyle choices? That is a related and slightly more complicated issue, which I shall deal with entirely in the second part of this article. 

P.S. I have split the subject into two articles to make it less tedious for the reader. A really long article would cause the reader's interest in the subject to wane midway. Apologies for that.