Q&A with the Authors

What sparked the decision for a sociologist and a bioethicist to co-author this book and engage in an experiment in productive disagreement? How did your different perspectives shape the project from kickoff to manuscript?

We met in 2016 through Sam's PhD advisor at Stanford. Over the next few years, we watched debate regarding the growing field of social genomics become increasingly polarized—protests at research presentations, bitter academic disputes at conferences, sensational headlines. A clear divide had emerged between those excited about the field's potential (Sam's camp) and those worried about repeating past harms (Daphne's camp).Despite standing on opposite sides of this divide, we both felt that nuance was being lost. People were talking past, rather than with, each other. Meanwhile, genomic technologies were racing ahead, moving from research labs into consumers' hands with potentially irreversible consequences. We decided to write a book that offers a more constructive way forward—one that provides a shared vision for using these powerful new tools to help people without deepening social inequalities.

The subtitle refers to “new technologies” and “old myths.” Can you unpack one of the most persistent myths about genetics that you challenge in the book, and describe how contemporary genomic tools are testing or reinforcing that myth?

Perhaps the most dangerous myth we tackle is what we call the Destiny Myth—the flawed belief that a person’s DNA determines their health, abilities, or life outcomes in a fixed and inevitable way. This idea is not new: fatalistic claims about genes date back to the dawn of the modern field of human genetics during the 19th century and have been used to justify grave moral ills, including slavery, forced sterilization, exclusionary immigration policies, and mass shootings. What's different now is that scientific advances are giving this old myth a modern sheen.

Many folks may not yet realize it, but we are in the midst of a pivotal moment when it comes to DNA and genomic technologies. For thousands of years, people have wondered about biological inheritance, but it’s just in the last couple of decades that scientists have collected enough DNA to make rigorous discoveries at scale. Previously, we could only link DNA to a handful of medical conditions like cystic fibrosis or Huntington's disease. Today, Americans can spend $50, spit in a cup, and receive genomic predictors called polygenic scores for everything from heart disease and depression to political preferences and intelligence. As these scores become more accurate, the temptation to treat them as destiny grows.

Some researchers, like the infamous Charles Murray (co-author of The Bell Curve), argue that recent genomic discoveries—paired with the fact that DNA doesn't change from conception—entail that efforts to reduce social inequality are futile. But this fundamentally misunderstands both genetics and society. As we show in What We Inherit, genes operate in constant conversation with their social and environmental contexts. DNA isn't destiny—it's one piece of a much larger, dynamic story.

Predictive genetic technologies like polygenic scores are a major focus of the book. How do you see these tools moving from the lab into real-world settings, and what are the most urgent risks and opportunities you uncover?

Despite our different academic backgrounds, we both share a deep concern about how quickly genetic technologies are entering everyday life. One striking example is polygenic embryo selection, which allows prospective parents undergoing in-vitro fertilization to select which embryo to implant based on its genetic characteristics. Parents can, for instance, use the technology to increase their future child’s expected height, or decrease that child’s risk of developing Crohn’s disease.

Many European countries restrict this practice, but the United States has virtually no regulation. This vacuum creates serious risks for consumers—the information companies provide is often unvalidated or inaccurate. And even when the science behind embryo selection doesn’t hold up, the belief that it works can shape parenting, identity, and inequality for generations.

Gattaca is no longer dystopic science fiction—many of the technologies it imagined exist today. The good news? It's still early enough to establish ethical oversight and thoughtful regulation. The train has left the station, but there's still time to steer it.

Your respective backgrounds emphasize that genes don’t operate in isolation: social context matters. Could you share an example from What We Inherit where a genomic finding would have been misleading or harmful without consideration of social environment or structural inequality?

When asked this question, we always think of Millie and Marcia Biggs—a pair of British girls who appeared on the 2018 cover of National Geographic with the headline "these twin sisters make us rethink everything we know about race." Marcia has light skin, blue eyes, and blonde hair, taking after their White mother. Millie has brown eyes, dark hair, and caramel skin, resembling their Black father. The fraternal twins inherited different DNA combinations that shaped their appearances—and, in turn, how others racially perceive them.

The difference in skin tone between the sisters is biologically innocuous. But it could profoundly impact their lives. Imagine Millie experiencing more discrimination due to colorism, which harms her mental health. Here, genes matter—but only because of the broader social environments in which they're expressed. In a world without racial bias, those same DNA variants wouldn't create different life outcomes.

This highlights a central challenge of the genomic era. Scientists have identified thousands of DNA variants linked to valued life outcomes, but we rarely know why a variant matters for a particular trait. A genetic mutation influencing depression might work through biological mechanisms like neurotransmitter regulation—or through social mechanisms like stigma and discrimination. Understanding context reminds us that while DNA helps to shape our lives, it doesn't determine them.

The book argues that we inherit more than DNA – we inherit ideas, assumptions, and practices. How does this broader notion of inheritance affect how we should approach regulation, public policy, and ethical oversight of genomic science?

Although the eugenics movement began in late 19th century England, it quickly spread to the United States, where it flourished on an unprecedented scale. Rules emerged about who counted as socially ‘fit’ enough to reproduce—and who didn't. During the first half of the 20th century, a majority of U.S. states enacted governmental programs to forcibly sterilize so-called undesirables. This eugenic campaign ultimately served as an inspiration for Nazi Germany and the atrocities of the Holocaust.

Many of the ideas, assumptions, and practices from our eugenic past remain largely unexamined, and most Americans still hold misguided beliefs about genes and human difference. Today's DNA revolution risks breathing new life into them. We must approach regulation, policy, and ethical oversight with this history firmly in mind—otherwise, we risk repeating it.

Given the rapid pace of genetic and genomic innovation, what are some “red flags” or warning signs you believe the media, public, or policymakers should watch for before uncritical enthusiasm or hype drives deployment?

Genomic innovation carries real promise but also serious pitfalls. Many technologies we discuss—from direct-to-consumer testing to polygenic embryo selection—currently offer highly inaccurate information. Yet they're already being marketed, sometimes at steep prices. Policymakers must hold companies accountable for overstating capabilities, and consumers need to learn to recognize when they're being misled.

Equally concerning are media headlines like “Britons are evolving to be poorer and less well-educated” or “Genetics outweighs teaching.” These narratives reinforce harmful myths like the idea that genes are destiny or that racial disparities are biological in nature. If a story seems too straightforward or too good to be true, it probably is.

On the flip side: What genuine promise do you believe these technologies hold if used thoughtfully? Is there a pathway you outline in the book for how genomic tools could contribute to reducing rather than exacerbating inequality?

One promising application is polygenic screening—using genetic scores alongside other factors to target interventions toward those who need them most. This could enable more efficient, equitable allocation of health and educational resources, improving outcomes and reducing preventable suffering. Early identification of at-risk individuals may also help people make proactive choices that promote long-term well-being. Some hospitals already use polygenic scores to screen adults for heart disease and various cancers, though it remains to be seen exactly how much these efforts will improve clinical care.

Another, more controversial avenue is polygenic embryo selection (discussed above). Though still imprecise, the technology is advancing rapidly. In theory, it could reduce the risk of serious inherited conditions—like the chronic pain Sam and his mother have experienced throughout their lives. Yet both of us are concerned about the use of polygenic embryo selection for other traits, like height or athletic ability. The real challenge ahead is determining for which traits are applications of the technology both accurate and ethical—and also ensuring access doesn't become limited to the wealthy. Without thoughtful oversight, these technologies could deepen rather than diminish inequality.

For readers coming from opposing sides of the debate, what is the one question you hope they walk away with after reading What We Inherit?

How can we harness the potential of new genomic technologies to improve lives while ensuring these same tools don't deepen existing inequalities?