We're all gonna die: Designer babies?

People tend to get all up in arms about "designer babies," by which I mean babies whose genomes are designed to have, or to not have (or to express or not express) certain traits. Wherever you fall on the issue, you will probably be surprised to know that in many respects, we are already genetically designing our babies, only we are doing so unwittingly and not to positive effect. For example, babies are in a sense "designed" through the food that women consume while pregnant. Yes, the food. You likely already realize that it's a bad idea to, say, smoke crack and/or drink while pregnant, but the food eaten during pregnancy may be equally important in terms of affecting the developing embryo. Take just two studies I read about recently as examples.

1. What a mother eats while pregnant can significantly affect the likelihood of her child becoming obese. (source)

2. A pregnant woman's exposure to pesticides can affect her child's IQ. (more)

How do effects like this occur? The answer lies in the fascinating field of epigenetics, which I learned about a few years ago via (what else) an amazing episode of Nova. As I am not a scientist or a science writer, I'll quote this Time article to explain the epigenome:

At its most basic, epigenetics is the study of changes in gene activity that do not involve alterations to the genetic code but still get passed down to at least one successive generation. These patterns of gene expression are governed by the cellular material — the epigenome — that sits on top of the genome, just outside it (hence the prefix epi-, which means above). It is these epigenetic "marks" that tell your genes to switch on or off, to speak loudly or whisper. It is through epigenetic marks that environmental factors like diet, stress and prenatal nutrition can make an imprint on genes that is passed from one generation to the next.

It's the biological expression of the "nurture" part of "nature vs. nurture"! Isn't that neat?

(Side note: I really wish I had found science this fascinating while it was still early enough in my life to consider science as a career. Social science is great and all, but it's mostly made up. You can quote me on that.)

In any case, it seems that the epigenome of developing embryos can be influenced by the mother's environment, including her diet. The University of Utah has a neat little site in which they explain how this process works, but it basically boils down to this: what a mother eats can affect whether her offspring express certain genes or not. Here is a vivid visual example of how prenatal diet can affect development (the picture comes from the University of Utah, but the experiment is also explained in the Time article I referenced earlier):

Crazy, right?

Which brings me back to my main point. I'm increasingly of the opinion that the rash of autism and obesity affecting Americans, to pick just two maladies of many, are not "random" occurrences: they are caused by something. Could we, in a sense, be designing obese autistic babies via the epigenome and the mother's diet? It's not outside the realm of possibility. I, for one, think that it's quite likely--and I haven't even addressed other environmental horrors that might be affecting unsuspecting embryos, nor the impact of what children are exposed to after exiting the womb. But I'll leave that last bit for another day. I've got some social science to do.

***

Related: Books on my Amazon wishlist that I know I shouldn't read but want to anyway: