Twenty years ago, in an essay entitled “The Wisdom of Repugnance,” Leon R. Kass warned that human cloning could one day simply be another option “with virtually no added fuss,” alongside IVF and other assisted reproduction techniques. Unknown to many, such a scenario is already materializing. In 2015, Britain became the first country to legalize a cloning technique for human pregnancy known as pronuclear transfer (PNT). Currently, it is only permitted for women with mitochondrial disease, which is passed on maternally. In January of this year, the first birth of a baby created using PNT—notably, not to prevent the inheritance of mitochondrial disease, but to “treat” infertility—was announced in Ukraine.

America is not far behind. Last February, the National Academies of Sciences, Engineering, and Medicine released a report saying that conducting clinical investigations of two “mitochondrial replacement techniques”—including PNT—is “ethically permissible” under certain conditions.

But how did all this happen, given that the thought of cloning still inspires repugnance? Where are the mass protests and the “Stop Human Cloning Now” picket signs? More importantly, how can we resist these developments? These questions are worth considering, since the stealthy rise of cloning holds valuable lessons about how science is perceived and what that means for ethical and public policy discussion.

Separating Fact from Fiction

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Our imagination about cloning has long been nourished by science fiction—Aldous Huxley’s Brave New World, for example, envisioned something of an embryo-splitting cloning method. Then there are popular films like The 6th Day, in which a clone wakes up in a lab as a fully-formed adult human being, with memories transferred into her brain. Arguably, these have contributed to the cultural force of the word “cloning.” But that can be a problem, when what passes as “cloning” in movies like The 6th Day is really fantasy.

Cloning is not, and never has been, the “photocopying” of an adult. Any human clone would still, like Dolly the Sheep, have to be implanted into a uterus as an embryo, undergo gestation, and be born in order to reach maturity.

Unsurprisingly, real-life cloning ends up looking far more “domestic,” or “banal,” than cloning in the movies. Perhaps, then, that is why many have not noticed that PNT, now legal in Britain, is in fact a form of cloning. Barely anyone has even spoken about cloning in relation to PNT or the other mitochondria-related technique that was legalized alongside it—the legislation referred to then as “mitochondrial donation,” while the media dubbed them “three-parent IVF.”

Yet arguably, PNT does constitute cloning. The facts of PNT are essentially this: nuclear DNA is extracted from an embryo that was created in vitro and carries the defective mitochondria of the woman commissioning the procedure. Meanwhile, another embryo created from a donor egg with healthy mitochondria has its nuclear DNA removed. The nuclear DNA of the first embryo is then transferred into the remains of the second embryo, creating a third embryo. The first two embryos are thus killed to form the new embryo—a clone of the first, but with mitochondria from the second.

Quite understandably, PNT challenges popular notions of cloning. It does not “look like” cloning to many people, simply because only one embryo survives. But, conceptually speaking, the procedure should count as cloning: a full set of chromosomes is transferred to create a near-perfect genetic copy of a preexisting life. That is what happens in the more typical form of cloning, which transfers nuclear DNA from an adult somatic cell rather than an embryo into an enucleated egg to create a new embryo. Some might argue that in PNT the same embryo survives the procedure—in other words, the first and third embryos are actually the same embryo, and so PNT is a kind of “embryo therapy.” But that is hard to believe when one considers that the maternal and paternal pronuclei of the first embryo may, in fact, be removed separately.

Why Words Matter

The failure to identify PNT as cloning has facilitated its introduction on both sides of the Atlantic. But this has also gone hand in glove with the use of various euphemisms that further disguise the nature of the technique.

Media reports about PNT did not generally mention cloning, but used terms like “three-parent IVF” or “three-parent babies” instead. Then there is “mitochondrial donation,” which sounds like organ donation, a practice accepted by many as ethical and even noble. Another option, “mitochondrial replacement,” suggests mitochondria being replaced, when it is actually nuclear DNA being replaced. To cap it all, an infographic on the BBC’s website about PNT used the term “embryo repair,” although none of the embryos involved is actually repaired.

To most readers, none of these terms suggests anything to do with cloning. Indeed, in some quarters, it was a deliberate decision to avoid using cloning-related terms. During a public briefing, the chair of the committee that produced the National Academies’ report explained the choice of the term “mitochondrial replacement,” saying that “nuclear modification” (which is actually what goes on) would connote cloning. Perhaps he too recognized that the choice of terminology can play a part in shaping perceptions and gradual public acceptance.

But the matter is subtler than just getting the right term. The developments of the last few years have slowly normalized PNT, and if one were to call it out as cloning now, that alone cannot be relied upon as sufficient to turn public opinion or policymakers against it. Although President Bill Clinton once declared, “Banning human cloning reflects our humanity,” such a sense of absolute disapprobation cannot be taken as given among the public or politicians in Britain and America today. And part of the growing problem is the gap between the cultural force of the word “cloning,” which inspires repugnance, and the increasing perception that perhaps cloning techniques like PNT “don’t look so bad after all.”

To come face-to-face with one’s adult clone, or an army of clone troopers—such cultural associations reinforce the repugnance of cloning, and rightly so. But if human cloning from adults is ever allowed for widespread use, I suspect it would only be for harvesting embryonic stem cells, which means embryo-clones of adults would be destroyed and never brought to term. And where human clones will be allowed to be brought to term, they will probably be clones of embryos destroyed in the process, as in PNT, rather than clones of adults. That way, nobody would ever see his or her clone walking on the streets. Not only, then, do actual cloning techniques look more “banal” than in the movies, but their effects on society would also seem fairly tame if implemented on such a limited scale.

Horrific as these techniques still are, repugnance at the idea of cloning would thus be minimized. After all, empathy with human life at the embryonic stage has not exactly been strong of late. Cloning would be easily perceived as being like IVF, where unimplanted embryos are already routinely destroyed.

The Task That Lies Ahead

All this leaves today’s bioethicists with a difficult task. As euphemisms help to disguise the rise of cloning, we must provide clarity about exactly what “cloning” means. Certainly, controversy over cloning terminology is not new. Take the distinction between “reproductive” and “therapeutic” cloning—a false distinction, because all cloning resulting in new embryos is reproductive. But today we still face confusion over what even counts as cloning, and with that comes the possibility of legal loopholes.

Two examples might illustrate how real that possibility is. In California, PNT would not be legally considered cloning, because cloning is defined as the creating of a human being for the purpose of pregnancy via nuclear transfer into an enucleated “human or nonhuman egg cell”—whereas PNT transfers nuclear DNA into an enucleated embryo instead. The situation in Britain, though, is arguably worse. The outright ban on human cloning for pregnancy, which defined cloning simply as the creation of an embryo “otherwise than by fertilisation,” was replaced by a section in the Human Fertilisation and Embryology Act that describes what would count as “permitted embryos.” In a way, this makes it easier to introduce cloning if a new category of “permitted embryos,” which describes a cloning technique without calling it such, is introduced—as it was with PNT.

Thus, a good understanding of what cloning means can help prevent cloning from being introduced through legal back doors, as it were. Although the force of the word “cloning” might slowly be called into question, I think there is still value in naming cloning when we see it—first out of pure honesty and respect for the truth, and second because contemporary Western society may well find its empathy for the embryo stirred by new developments in embryology, even if they are not always the result of ethical experimentation.

Last year’s breakthrough in culturing embryos to thirteen days, for instance, revealed just how autonomous embryos are. Recent news of human-pig hybrid embryos provoked much disgust—the mere thought of an animal embryo carrying human cells. It is possible that as our understanding of and power to manipulate embryos increases, so might our ability to recognize that embryos are already the same organisms as the adults they will become.

But the contemporary bioethicist’s task has a second dimension. The bioethicist must also convince others that, despite the relative banality of real-life cloning, repugnance is still amply justified. That requires more than just semantics. Particularly if cloning is only introduced on the limited scale I described earlier, and advertised as “therapeutic,” we need a renewed understanding of what the object of our horror is.

And wherein lies that horror? The fact of cloning is one part of it, of course, and if empathy with the embryo does grow, it will become more apparent that even cloning from embryos is a willful disrespect of individuality, and killing a weaker or diseased embryo in the process is simply eugenic. But what must also be countered urgently is the notion that cloning for embryonic stem cells, or for disease-free embryos, is somehow “therapeutic”—for it is this claim that will perhaps help sell cloning to the public more than anything else.

We must hence be clear: with techniques like PNT, no one is cured. Rather, such techniques ensure that only human beings deemed sufficiently healthy will be allowed to live. We must confront the harsh reality of technologies like PNT and cloning for embryonic stem cells, which create a human life in a lab only to end it and harvest “spare parts.” That is anything but “therapeutic.” Even for those who do not recognize the embryo’s moral status, it should be easy to see how these cloning methods might adversely affect the way our culture views human life. And that is why human cloning, however banal it may appear, must be resisted.