I’m back again for a bit and, once again, starting with a post rather than comments. Last time I did this it meant I didn’t get to the comments, for which I apologize. I think I’ve a pretty good chance of doing it all today.
A while back I posted about a book called “Origins.” It’s about the importance of fetal origins (by which the author means the period in utero) in human development. I originally posted about media coverage generated by the release of the book, but I did get around to actually reading the book, which I found disappointing. My advice would be to stick with the media coverage.)
The idea here is that the fetal environment turns out to have a great deal of influence of the development of the child who is eventually born. Some of this is hardly news–think of Fetal Alcohol Syndrome. But research seems to show much more far-reaching influences.
In that context, consider this news report about a recent study which is taken from last week’s NYT. The study looked at the incidence of autism in identical twins, fraternal twins, and non-twin siblings. Identical twins have identical DNA, but fraternal twins have as great a genetic relationship as do an siblings–their DNA comes from the same two people.
What I’ve come to expect are studies about people who share identical twins and how they share more traits than fraternal twins or siblings and how this shows the importance of DNA. But that’s not the story here.
What is striking here is that the rate of autism in pairs of fraternal twins is higher than the rate of autism in pairs of siblings who are not twins. Genetically speaking, there is no difference between fraternal twins and any pairs of siblings, so something other than genetics must explain this. So what is it that fraternal twins have in common that pairs of siblings do not? The fetal environment. Fraternal twins are in utero together. Non-twin siblings are in utero at different times and hence, in different environment.
Thus, it appears that the fetal environment (which they refer to as an “environmental factor” in the study) are a significant factor in the occurance of autism. Indeed, the conclusion of the study is that austism “has moderate genetic heritability and a substantial shared twin environmental component”–suggesting that the environmental factors are more important than the genetic ones.
The implications here are interesting, though of course this is only one study and one should procede with caution: The period of pregnancy matters to development–and perhaps matters a great deal.
There are two ways in which this is important for my topic here–both of which are raised in that earlier post on this topic. First, and more narrowly, what does this mean for surrogacy? I’m thinking particularly about the international outsourced surrogacy practiced in India and other places.
It seems to me that it is in this context that there is the greatest risk that the women who are pregnant are treated like vessels. I don’t have the sense that the selection of surrogates is made with the same considerations as is the selection of gamete providers. And I don’t have the sense that the conditions of the surrogates during the pregnancy are viewed as part of the formative environment–except to the extent the women may be kept in compounds so that they can be assured proper nutrition and denied access to harmful substances. It’s hard to imagine these practices would persist if we all thought that the in utero environment was an important determinant of subsequent human development. Indeed, if we accept that, then I think the practice of surrogacy will change and will come to more closely resemble the practices around selection of third-party gametes.
Second, and more generally, this study demonstrates the importance of the contribution to human development made during the process of pregnancy. This, it seems to me, strenghtens the claim of a woman who is pregnant/gives birth to some sort of important legal status vis-a-vis the resulting child. In my book this would be legal parentage, of course.
I’ll stop now. I recently learned the phrase “teal deer” and I want to avoid earning that mark. More to follow, though.