Let the record show that epigenetics is fast becoming the top topic in pop science. Every day Google Alerts lets me know about two or three new pieces on the subject. Epigenetics, a formerly obscure branch of genetics, studies how social and environmental forces wreak heritable changes on the activities of genes without tampering with their underlying nucleotide sequences. Some of the news items come from science journals and magazines, but almost as many are published on general-interest websites like the Huffington Post, the BBC, and The New York Times.
Epigenetics is genuinely exciting because it provides surprising new ways to think about a huge range of old problems: Someone’s using it to solve some of the mysteries of cancer, someone else is unraveling the complexities of bee society. But the epigenetic discoveries that gin up the most editorial excitement somehow always seem to involve mothers. “Smoking Mothers May Alter the DNA of their Children,” warned Science this month. “Parenting Style Affects Children’s Genetics,” stated the Patheos website, also this month, in an article that wed epigenetics to mother-child attachment theory. “How a Pregnant Woman’s Choices Could Shape a Child’s Health,” appeared on NPR.org this fall.
What these headlines refer to is research coming out of a sub-discipline of epigenetics called DOHaD, the developmental origins of health and disease. DOHaD focuses in large part on the unfolding of the fetus and the maturation of the toddler, analyzing in particular how parents’ and even grandparents’ eating and drinking habits, stress, toxicity intake, weight, and other behaviors and states of mind or body can subtly revise the genetic prompts that turn the undifferentiated zygote into a mostly formed little person, with a health profile that may dog him or her for a lifetime. In an editorial published this week in Nature, seven academics led by Sarah Richardson, a Harvard professor of the history of science and of gender studies, warned that reporting about DOHaD, especially if it’s “exaggerated and oversimplified,” holds risks for pregnant women; it could make “scapegoats” out of them and maybe even increase the “surveillance and regulation” of their behavior.
So are the writers being alarmist in a way that might taint important scientific research, undercut its credibility, and jeopardize its funding? Or do they have good reasons to worry? Yes and yes. If people started associating epigenetics with mother-bashing, that could damage its standing, especially in the politically hypersensitive climate of universities. On the other hand, fetal medicine has been used to restrict the rights of women since the advent of modern embryology in the late nineteenth century. In 1908, after decades of medical activism on behalf of fetuses, the Supreme Court upheld a law that barred women working in factories and laundries for the usual ten hours lest their “performance of maternal functions” be impaired; this sort of workplace discrimination continued in one guise or another until another Supreme Court ruling in 1991 forbade companies to deny certain jobs to women, such as working with chemicals, in the name of fetal protection. In a nice coincidence, “fetology” was declared a medical specialty in 1973, the same year the Roe v. Wade decision made abortion legal, and gave intellectual ammunition to the war against it. To take just one example, obstetricians often sided with hospitals that wanted to force caesarean sections or blood transfusions on women who refused them for, say, religious reasons—an obvious call, you might say, if you didn’t happen to be a Christian Scientist, but one that undermined the autonomy of women and bolstered the notional personhood of the fetus. Today, we have a fetal-rights movement, fetal homicide laws in 39 states, and an infamous “chemical-endangerment” law in Alabama. Women have gone to prison and even given birth in shackles for taking drugs while pregnant or doing other things deemed hurtful to their unborn children.
As the Nature editorial also points out, the scientific grounds for criticizing or regulating the behavior of pregnant women are almost always shakier than they look at first. Despite waves of hysteria about crack babies and drinking while pregnant, the latest research shows that smoking crack’s not as bad for babies as smoking tobacco, while having a glass of wine now and again now appears to be perfectly fine. Epigenetics is in its infancy; much of its work has been done on rats and other animals whose “short lifespans and large litter sizes” make them “poor proxies for human reproduction”; and even the best science journalism can be reduced by lay readers to a set of jingoistically monocausal theories: a mother’s high-fat diet will cause cancer in her offspring. If you get the flu during pregnancy, your child will be autistic. “Intrauterine exposures can raise or lower disease risk,” write the authors, “but so too can a plethora of other intertwined genetic, lifestyle, socio-economic and environmental factors that are poorly understood.”
It’s those “socio-economic and environmental factors” that give epigenetics its really radical edge. The famines resulting from wars or climate change that deny future mothers and fathers the nutrition needed to make healthy babies; the extreme stress accompanying poverty and racism that lastingly transmogrifies neurological and endocrinological systems, so that both parent and child are quick to anger and hard to soothe; the environmental injustice that shunts vulnerable populations into polluted neighborhoods—social disasters like these, we are learning, leave much deeper and demographically more significant traces on children’s neurobiological development than the stupid stuff that some women do when they’re expecting.
Moreover, epigenetics’ most unexpected discovery has been that the experiences of fathers and grandfathers can have as great an impact on their children, if not a greater one, than those of mothers and grandmothers. After all, men make sperm their whole lives long, while women are born carrying all the eggs they’ll ever release. That means that male reproductive material has more time to react to toxins, junk food, and the vicissitudes of adversity, and transmit the consequences to their descendants by epigenetic means. So when it comes to, for instance, shielding people from workplace conditions that could damage future generations, it looks like men need at least the same level of protection as women do—a feminist demand since 1920, by the way, when a paper from the Women’s Bureau of the U.S. Department of Labor stated, “Safe standards of work for women must come to be safe standards of work for men also if women are to have an equal chance in industry.” In other words, epigenetics can bolster feminism; it doesn’t necessarily militate against it.