Beyond Designer Babies: Epigenetic Modification May Be the Next Game-Changer

HORROR, EAGER ANTICIPATION, and every sentiment in between swirl around the prospect of designer babies. The most recent spate of articles, TED Talks, and conferences about the subject has been triggered by the discovery, announced in 2015, of a potent new method for modifying DNA — the CRISPR/Cas9 pathway. Biologists are elated about its heady potential for precisely modifying the genomes of organisms ranging from plants and animals to, yes, humans themselves. But while they’re elated, many of them are also wary because many of these modifications would be heritable; this innovation, they argue, may therefore warrant a moratorium so that societal and moral implications can be fully assessed.

Ongoing efforts at self-regulation among leading scientists in the field certainly deserve our respect and support. But what seems to have gone relatively unnoticed over the last decade is the development of a separate but equally potent pathway for genetically engineering — and thus redesigning — human bodies and minds: epigenetics. Over the coming decades, altering our kids’ DNA may not be the most appealing way to proceed. In fact, if the cutting-edge field of epigenetics fulfills its promise, the hoopla over designer babies may end up being misplaced. “Designer adults,” created through epigenetic modification, may instead be the real game-changer. In such a world, bioenhancement tools used by today’s “body hackers” like Peter Thiel and Ray Kurzweil — transfusions of youthful blood, elaborate daily regimens of pills and potions — would seem as crude and quaint as the leeches of yesteryear.


The more scientists learn about the functioning of genes, the more they emphasize the molecular factors regulating genetic expression — how certain segments of DNA code are activated and others deactivated. It turns out that many of our 20,000 genes are constantly being switched on and off in complex chronological sequences and combinations. When scientists speak of an epigenetic process, they are referring to these molecular mechanisms that change the expression of genetic information without altering the underlying DNA sequence itself. In other words, the DNA code remains the same, but certain portions of it are selectively silenced while others are spurred to action.

Scientists are only just beginning to understand the intricate dance of molecular mechanisms through which epigenetic modifications take place. But as their understanding deepens, a new vehicle for genetic enhancement is likely to become available. Instead of directly modifying the underlying DNA code in our cells, we could operate indirectly — altering the epigenetic mechanisms that modulate the DNA code’s expression.

The advantages of this indirect method would be significant. Epigenetic modifications would be much easier to implement than genetic ones because our epigenomes are already primed to respond to shifting environmental conditions or trigger events. When we go on a diet, for example, our bodies respond by altering our metabolism, and part of this adjustment is carried out via epigenetic modulations. Even when we engage in transitory acts like stepping into a sauna, our bodies make epigenetic adjustments as they struggle to maintain homeostasis in the sweltering heat. Such mechanisms could eventually be systematically harnessed to bring about far-reaching changes to our bodies and minds.

Epigenetic science is still too young for us to determine how effective an instrument it will become — whether for healing the sick or enhancing the healthy. But if it pans out, it could open a whole new “instrument panel” for modifying the ongoing operation and expression of our genes. We could flexibly exploit this mechanism at any point in our lifetimes, refining the modifications already made as the science grows more sophisticated. We could tweak, adjust, boost, and upgrade our bodies and minds at will. The modifications we make in youth — for example, boosting physical stamina and dexterity — may seem less interesting in our 30s, when we’re perhaps more likely to explore new dimensions of cognitive boosting and mood modulation. Such a technology, in short, would allow us to sculpt our bodies and minds on an ongoing basis, as a lifelong project — a genetic work-in-progress.


By allowing adults to undertake modifications on themselves after they have come of age, epigenetic technology would also bypass one of the thorniest moral problems raised by the prospect of designer babies: the question of consent. Suppose, for example, that one day you found out you were a designer baby. What would it be like to imagine the conversation between your parents when they sat down to negotiate the desired trait parameters for the human being who was eventually to become you? In today’s society, parents certainly make choices that profoundly affect the well-being of their children — which city to live in, what school to attend, what house of worship to join (if any), and so on. Nevertheless, the child still has a significant measure of autonomy in choosing how to respond to these parental decisions. She may resist, she may go along wholeheartedly, she may pretend to go along wholeheartedly — the decision is ultimately hers. But the shaping of one’s innate trait profile is quite another matter: it affects the fundamental platform of capabilities, attitudes, preferences, and propensities that make up our identities. If this platform has been modified by my parents, I may find myself wondering: to what extent are my reactions, the tenor of my thoughts, my visceral likes and dislikes, partially preprogrammed into me by them from the start?

At the heart of the matter lies the very nature of autonomous volition itself, which is predicated on my possessing distinct individuality and agency: a sense that I can make my own choices. Most developmental psychologists would agree that values, tastes, and preferences emerge gradually, through the dynamic interaction of my innate unbidden characteristics with my experiences and environment. They inform the continuously evolving, emergent whole that is my personhood.

A key assumption in this equation is that the genetic component of this process lies beyond direct human control. It is not subject to the preferences of other people. Rather, it constitutes a basic constraining factor that limits the extent to which others can influence my development and behaviors. (For example: “You may do everything in your power to make me choose a career in the family business, but you will never be able to suppress the free-spirited musician in me.”) In this sense, it is like a kind of internal ballast in the ongoing formation of my identity over time. When I say that my values, tastes, and preferences are my own, it is to this delicately balanced causal interplay of external and internal factors, nurture and nature, that I am implicitly referring.

However, if I start out life as a designer baby and thus with my genome actively shaped by my parents, then this balance has been disrupted. When I exercise my volition, I may feel as though I am exercising my own will, but a portion of the factors that determine this choice will now derive from decisions made on my behalf before I was born. These are certainly still my values, tastes, and preferences — I have no other basis from which to make my choices. But they also bear the partial signature of the preferences my parents had in mind when they selected certain components of my genome. My autonomy is therefore partially diminished, and the very boundary between “mine” and “theirs” slightly but irrevocably blurred.

Epigenetic modification sidesteps this moral problem because it can be adopted by mature adults meeting the criteria of informed consent. What is more, such “designer adults” would enjoy another key advantage over designer babies: their genetic modifications would not become obsolete with the passage of time. If someone modifies your genome at conception, and those DNA modifications propagate throughout the cells of your body as it develops, you are stuck with those changes for the rest of your life. But genetic science will of course not come to a halt. Indeed, with each subsequent decade, scientists and doctors will learn more about how genomes work and develop ever more refined techniques. People who adopt epigenetic modifications will therefore be poised to take advantage of the very latest forms of intervention — and at least some modifications will be reversible, allowing further tweaks and upgrades down the road. These two advantages — availability of consent and avoiding obsolescence — should not be underestimated. They suggest that, if human genetic enhancement does become widespread over the coming decades, then we are far more likely to encounter “designer adults” in our midst than designer babies.


Should this be cause for celebration? Not necessarily. Regardless of which avenue consumers end up choosing — epigenetic or DNA (or a combination of both) — the prospect of a civilization in which millions of individuals are messing around with their genetic makeup is a disturbing one. We hardly need say that the benefits and risks would be unprecedented in nature.

Epigenetic enhancement would no doubt be coupled with novel forms of pharmaceuticals and potent bioelectronic devices linking people to a broad array of brilliant machines. In such a world, humans would enjoy vast new powers over their surroundings and interior lives. Some of these bioenhanced capabilities will be splendid to behold and experience. People will live longer, healthier, and more productive lives; their augmented minds will generate staggeringly complex and subtle forms of knowledge and insight.

At the same time, the widespread adoption of these technologies will create formidable challenges. If rich people enjoy greater access to potent bioenhancements, then this will exacerbate the already grievous rift between haves and have-nots. In parts of the world where millions lack sufficient food, clean water, and basic education, it is difficult to see how expensive enhancement technologies can be made broadly available. We may therefore witness the emergence of an even starker divide within the global population, with far more deeply etched differences because they are now biologically based, and not just environmental or cultural.

Moreover, even within rich nations, competition for the most sophisticated enhancement products will be relentless, for an individual’s professional and social success will be at stake. As these technologies advance, they will continuously raise the bar of “normal” performance, forcing people to engage in constant cycles of upgrades and boosts merely to keep up — “Humans 95, Humans XP, Humans 10.” People will tend to identify strongly with their particular “enhancement profiles,” clustering together in novel social and cultural groupings that could lead to new forms of prejudice, rivalry, and outright conflict. Individuals who boost their traits beyond a certain threshold may acquire such extreme capabilities that they will no longer be recognized as unambiguously human.

Some bioenhancements may offer such fine-grained control over feelings and moods that they will risk turning consumers into emotional puppets. Imagine, for example, that you could modulate the tone of your emotions from moment to moment, hour to hour, simply by popping a series of pills whose effects were precise, immediate, and free of unwanted side effects. What happens to the ideal of authenticity in such a context? What happens to our sense of personal identity when the contents and feeling-tones of our conscious awareness can be so freely and precisely steered? Who is the real me?

Until recently in human history, the major technological watersheds all came about incrementally, spread over centuries or longer. People and social systems had time to adapt: they gradually developed new values, norms, and habits to accommodate the transformed material conditions. But this is not the case with the current epochal shift. This time around, the radical innovations are coming upon us with relative suddenness — in a time frame that encompasses four or five decades, a century at most.

Some of the factors propelling this process will reflect our baser nature: greed, competition, envy, and lust for power. Others will arise out of noble sentiments: a desire to see our loved ones live healthy lives and succeed; a thirst for novelty; the aspiration to attain higher forms of achievement, knowledge, and sensation. These forces will be hard enough in themselves to resist, but they will be further amplified by the involvement of large-scale business interests and the allure of major profits. This nexus of impulses and ideals, and of economic and social forces, will generate a seemingly irresistible pressure to go faster, faster, faster in adopting such technologies.

And yet restraint is clearly the smarter path — deliberately postponing radical forms of self-modification until our society has had a chance to gauge the consequences and acclimate to them. Indeed, if we permit these kinds of bioenhancements to advance too quickly, the resultant social stresses would most likely destabilize our civilization. The likelihood of major unintended effects should impel us to proceed slowly, cautiously, and with great humility as we go down this road.


Michael Bess is Chancellor’s Professor of History at Vanderbilt University. His most recent book is Our Grandchildren Redesigned: Life in the Bioengineered Society of the Near Future (2015).