These epigenetic switches are being set one way or another

Via Timothy Taylor in Fetal Origins and Epigenetics: Interview with Janet Currie. The Human System is multivariate, complex, chaotic, non-linear, homeostatic, self-correcting, contextually sensitive, dynamic, heterogeneous and ridden with tipping points and hidden feedback loops. I suspect that research in epigenetics will be extremely fruitful as well as tremendously problematic.

Just imagine the implications. We at one time sought to ameliorate poverty by simply transferring money from adults to adults. That turned out to be a bandaid and did not fix the underlying problem of family dysfunction. We then changed our focus to the children of poverty and invested in schools and programs. No fixes. We then shifted our focus further upstream to programs such as Head Start. Still no fixes. Now, with epigenetics, we are headed yet further upstream. But what are some of the implications? They are huge for issues of gender roles, right to life vs. choice, sociological impacts, etc.

One of the things I talked about in my Ely lecture was what mechanism might underlie the long term effects, and I raised the idea of “epigenetic” changes as one possibility. The way I like to think about that is you have the gene, which only changes very slowly when you have mutations. But then kind of on top of the gene you have the epigenome, which determines which parts of the gene are expressed. And that can change within one generation. There are animal experiments that do things like change the diet of guinea pigs and all the baby guinea pigs come out a different color. It can be pretty dramatic. ... The idea is that the fetal period might be particularly important because these epigenetic switches are being set one way or another. And then once they’re set, it’s more difficult to change them later on.

I think we haven’t really been able to look at all of the implications of that given the limitations of the data. We don’t have very much data where we can follow people from, say, in utero to some later period. But, that’s where the frontier is, trying to do that kind of research and make those linkages....

I think a really interesting thing about the fetal origins hypothesis for public policy is that if it’s really important what happens to the fetus, and some people think that maybe the first trimester is the most important or the most vulnerable period, then you’re talking about women who might not even know that they’re pregnant. It really means you should be targeting a whole different population than, say, 15 years ago, when we thought, oh, we need to be targeting preschool kids instead of kids once they reach school age. Now we’re kind of pushing it back. Then it was, “We need to be playing Mozart to infants.” Now the implication is that we’ve got to reach these mothers before they even get pregnant if we really want to improve conditions.

Epigenetics implies that it does not make sense to talk about nature versus nurture. If nature is the gene and nurture is the thing that sets the switches, then the outcome depends on both of those things. So you can’t really talk about nature or nurture in most situations. It has to be some combination of both.

"It has to be some combination of both." - Too right as they say in some parts of the world. Epigenetics is one of those knowledge frontiers that well warrants further study.