Who is a Biological Parent?
A pet peeve of mine is the use of the term biological parent as a synonym for genetic parent, especially in the context of surrogacy contracts. What’s wrong with this? First, it defines parenthood in terms of the connection that men have with their biological children. As sociologist Barbara Katz Rothman has pointed out, we wrongly discount pregnancy and birth when we speak of a “blood” relationship between parent and child as “the metaphorical blood of the genetic tie,” rather than “the real blood of pregnancy and birth … the mingled blood of mothers and their children.” I developed this point in an article a few years ago, arguing that a gestational mother is a “biological mother,” for purposes of Supreme Court precedent that treats a biological relationship as a prerequisite for a constitutional claim of parental rights.
Second, in the course of my current research project, I’ve learned more about why “biological parent” is inaccurate when used to exclude a gestational mother. The developing field of epigenetics studies how genes interact with environmental factors that influence gene expression–whether, when, and how particular genes are turned “on” or “off”. It turns out that the environment–including the “gestational environment”–can have heritable effects. For example, the diet of a pregnant mouse can be manipulated so that her offspring are either black or yellow, even though they are genetically identical. That isn’t surprising. What is surprising, however, is that the effect persists into the next generation, as part of the heritable “instructions” that are passed down from one generation to the next, still without a change in DNA. Even if we define parenthood on the basis of the transmission of heritable traits, gestation seems to qualify.
This research has had an interesting reception in the reproductive technology industry. Agencies that sell “donor eggs” have touted epigenetic research in order to reassure recipients that they are “real” mothers by virtue of gestation, even if they don’t provide DNA. On the other hand, participants in surrogacy arrangements tend simply to reject the claim that the gestational mother can affect who the child is.