Twenty-seven years ago, Ty Lawrence began to be haunted by a slab of meat.
The carcass, which he spotted at a slaughterhouse while doing research as a graduate student, defied the usual laws of nature. The best, highest-quality steaks—picture a rib eye festooned with ribbons of white fat—typically come from animals whose bodies yield a relatively paltry amount of meat, because the fat that flavors their muscles tends to correspond to an excess of blubber everywhere else. This animal, by contrast, had tons of fat, but only where it would be delicious. “In my world,” Lawrence told me, “people would say, ‘That’s a beautiful carcass.’ ”
As Lawrence watched the beef being wheeled toward a meat grader that day, an idea hit him: We should clone that.
The technology existed. A couple of years earlier, in 1996, scientists at the Roslin Institute, in Scotland, had cloned Dolly the sheep. Lawrence lacked the funds or stature to make it happen, but he kept thinking about that beautiful carcass, and the lost potential to make more like it.
He was gathering data at another slaughterhouse in 2010 when, late one evening, he spotted two carcasses resembling the outlier he’d seen years before. Lawrence—by then an animal-science professor at West Texas A&M University—immediately called the head of his department. It was nearly 11 p.m. and his boss was already in bed, but Lawrence made his pitch anyway: He wanted to reverse engineer an outstanding steak by bringing superior cuts of meat back to life. He would clone the dead animals, and then mate the clones. “Think of our project as one in which you’re crossbreeding carcasses,” he told me.
A few years later, Lawrence and his team turned two tiny cubes of meat, sliced off exceptional beef carcasses at a packing plant, into one cloned bull and three cloned heifers. After breeding the bull with the heifers, Lawrence slaughtered the offspring to assess the quality of the meat, and found it to be just as terrific as the originals’. The next generation’s meat was even better than that—superior, even, to that of animals bred from the cattle industry’s top bulls.
Ranchers who are keen to mimic Lawrence’s results have since bought thousands of straws of semen from his bulls. One even tried to purchase his entire stock of sperm and animals, though Lawrence declined. The clones’ offspring and their offspring have, in turn, entered the food supply. “The progeny of the clones would’ve been eaten by, oh, I don’t know, tens of thousands, hundreds of thousands of people,” Lawrence said. Of the four original clones, two have died of old age. The remaining two are still on the university’s ranch—“grazing, drinking water, living their best second life,” Lawrence told me.
Increasing numbers of animals are getting a similar do-over. In the three decades since Dolly proved that a fully grown mammal could essentially be reborn, cloning has proliferated. By now, nearly 60 different species and subspecies have been cloned, including fruit flies, fish, frogs, ferrets, French bulldogs, and monkeys, a feat long thought to be nearly impossible, given the architecture of primate eggs.
Once confined to research labs, the technology has become reliable and lucrative enough to be the basis for companies around the world, which are churning out clones of super-sniffing police dogs, prizewinning show camels, pigs for organ transplantation, and “high-genomic-scoring” livestock—which is to say, ultra-lactating dairy cows and uncommonly tasty beef cattle. The top-ranked polo player, Adolfo Cambiaso, has more than 100 clones of his best horses and once won a match riding six copies of the same mare at different points throughout the competition. At a 2023 championship game, all four members of his team rode clones of that mare to face off against their opponents—who were mounted on the clones’ offspring. A video homage to the cloned horse listed her birth and death dates as “3 February 2001–∞.”
The public hasn’t necessarily warmed to this genetic tinkering, which strikes many as creepy: As of 2023, a majority of Americans opposed cloning, in almost equal numbers as when Dolly was born. But whether or not they realize it, many thousands of clones have already been produced as the cloning process has become more and more routine. “We passed the number of where we kept track a long time ago,” says Diane Broek, an embryologist and a sales manager at Trans Ova Genetics, which specializes in cloning livestock. If you want a clone today, you’ll probably have to join a waiting list.
Many clones start their lives as a paste of bloody cells in a mirrored-window storefront that sits between a quilt shop and Diamond S Rustic Decor in Whitesboro, Texas (population 3,852, according to a road sign). Whitesboro is the headquarters of ViaGen Pets & Equine, the world’s leading producer of cloned cats, dogs, and horses. “That’s what we usually get: It’s like, ‘You do what in there?’ ” a receptionist said when I visited this past fall.
ViaGen’s waiting area had the antiseptic comfort of a doctor’s office, complete with several magazines on animal husbandry and a struggling houseplant. Beyond that was a long corridor flanked by brightly lit rooms that held lab equipment, freezers, and several of the embryologists who are among ViaGen’s nearly two dozen full-time employees.
Technically, a clone is a genetic replica of another living creature that is “made”—professional cloners refer to themselves as making animals—without any of the sexual athletics that traditionally accompany reproduction. This level of human control over the biological order of things has provoked concern that these companies are playing God. In an effort to dispel misgivings about the technology, cloning firms have almost universally adopted the tagline that a clone is “an identical twin born at a later date.”
The late billionaire founder of the University of Phoenix established ViaGen in 2002 by licensing patents from the lab that cloned Dolly. Eventually, his family’s mutt was cloned four times. (This was done by a lab in South Korea, as ViaGen wasn’t yet offering pet cloning.)
Cloning has since been embraced by wealthy clients accustomed to having their desires catered to exactly. Past ViaGen customers include Barbra Streisand, who received three clones of her late Coton de Tulear dog, and the family of Pablo Escobar, which cloned a horse.
ViaGen’s office is hung with dozens of portraits of saucer-eyed kittens and bow-tie-wearing puppies—all made in its lab. “Lasting Love” is the company’s slogan, and its website features nearly 200 endorsements from pet owners, such as the grieving companion of the late Ceaser the cat, who writes, “What’s a splurge on luxury items when you can bring back a piece of your heart that you thought was broken forever.” The lasting love does not come cheap: $50,000 for a cat or dog, or $85,000 for a horse, payable online via credit card with all the ease of buying a blender. Once cloning is complete, the company provides clients with a DNA test, performed by an independent lab, confirming that the resulting baby is, in fact, a clone.
ViaGen eagerly shares the emotional rewards of cloning, but it can be less forthcoming with certain details about the process itself. To copy your animal, you must first send ViaGen a few pieces of its flesh, which will be used to grow new cells to supply the DNA for the clone. If the so-called founder animal is still alive, ViaGen suggests a sunflower-seed-size patch of skin from someplace it won’t be missed, such as the abdomen. If the clonee is dead, the company requires a sliver of ear—“For some reason, that grows really, really well,” a ViaGen technician told me—which should be sliced off within five days of the animal’s death and kept chilled but not frozen to avoid being damaged. Exceptions can be made. Once, a customer sent in the room-temperature scrotum of a sheep that had been dead for nearly a week.
Your animal’s tissue will be minced with a scalpel, bathed in a solution of nutrients and antibiotics, then put into an incubator that mimics the environment of the mammalian body. “Each one of the cells in there has the blueprint to make an animal,” Shawn Walker, ViaGen’s chief science officer, told me as we bent over an incubator to inspect a clear plastic flask where thousands of dog skin cells were proliferating in pink goo. The growing cells need to be regularly supplied with the nutrient mixture, and the incubator was fluttering with Post-it-note reminders to “feed Thursday.”
After about a week in the incubator, ViaGen will harvest a minimum of 1 million cells from the flask—a sample that, in theory, could be grown and regrown to make an infinite number of copies of the original animal. ViaGen will then freeze the cells until the client is ready to clone. Currently, ViaGen’s record for the most clones for a single customer is 50 horses, the company’s CEO, Blake Russell, told me. “And there have been lots of clients”—who also cloned horses—“in the 20s.”
Although ViaGen says it has introduced its own refinements over the years, the cloning process, called somatic cell nuclear transfer, still follows the same basic steps first developed in 1952 by researchers in Philadelphia to copy a frog embryo. It requires removing an unfertilized egg (an oocyte) from a donor animal, then wiping it clean of its own DNA so it can carry the clone’s. Working at a microscope beside a photo of Paris Hilton posing poolside with her cloned Chihuahua, a ViaGen lab technician uses a glass-tipped pipette to suck out the oocyte’s genetic material and, in its place, insert one of your animal’s newly grown cells, which contains its DNA—and thus all the information, from fur hue to leg length, to grow a twin.
When animals mate the old-fashioned way, sperm cells have to contribute their genetic information to the oocyte; in this case, they’re irrelevant. The lab technician zaps the egg with a static-electricity-strength electrical pulse that stimulates it to divide, and after a few more days in a body-temperature incubator, you have the embryo of a future clone. Dog, cat, and horse embryos are each kept in separate units. “We wouldn’t want a mix-up,” Walker said.
Now you need an animal to impregnate.
For this, ViaGen frequently turns to a 70-year-old veterinarian named Gregg Veneklasen, who, in his 22 years working with the company, has had extensive experience dealing with the most contentious and least publicized parts of the cloning process: supplying eggs and wombs, and, when all goes well, delivering healthy baby animals.
Veneklasen, whose chest-length gray beard and rotating aloha shirts bring to mind Moses by way of Margaritaville, runs a vet clinic with a lived-in homeyness that is a far cry from ViaGen’s buttoned-up operation. Located just outside Amarillo, Texas, a landscape of such unending red flatness that it looks like it was created by copy and paste, the clinic has bookshelves overflowing with animal bones; its floor is covered with stacks of textbooks, and its waiting room is presided over by a pair of languid tortoises. While scientists at ViaGen’s headquarters handle the sterile lab work involved in cloning, Veneklasen and his colleagues—including a pair of identical twins he calls “my human clones”—are busy ultrasounding fetuses with their arms up mares’ rectums and watching newborns take their first wobbly steps.
One morning, I arrived at Veneklasen’s office to find him sitting at his desk in the dark with blood on his work boots and crimson smears of placenta in his beard, wearing the same aloha shirt he’d had on the day before. He’d been at the clinic since 4:30 a.m. helping a mare deliver a clone, the second version of the same bucking horse born in as many days. “It’s pretty cool,” said Veneklasen of the newborn. “That thing was a piece of skin.”
Though Veneklasen specializes in horses, including million-dollar rodeo mounts and champion polo ponies, his fascination with reproduction has inspired him to tackle more offbeat cloning projects with ViaGen, including big-antlered deer for sport hunters, an endangered Przewalski’s horse for the San Diego Zoo, cattle for Ty Lawrence’s study at West Texas A&M, and genetically modified feral pigs with bright-orange snouts (to tell them apart from regular swine)—hundreds of animals in total.
Veneklasen guided me into a barn crowded with knee-high metal canisters that together contained a small cavalry of frozen clone embryos from ViaGen awaiting transfer into mares. He opened the top of one container, which spewed clouds of liquid-nitrogen vapor as he removed a metal basket of what looked like plastic coffee stirrers, each with a yellowish-white lump at the bottom: the embryo. Later, I’d watch a vet thread a thin stainless-steel syringe through a mare’s vagina, then deposit the embryo in her uterus with the push of a plunger.
Veneklasen had started saving each straw as a keepsake after it had been emptied, and dozens of them were taped to one wall of his barn, like baby photos at a pediatrician’s office. “There’s a Whistle, there’s a Bobby Joe,” he said, reading the names of cloned horses handwritten on the straws. “There’s another Whistle—they wanted tons of Whistles.” He rattled off a couple more, then immediately backtracked and asked me not to print one of the names. “This guy—I don’t know why, but he doesn’t want anybody to know.”
Plenty of people won’t cop to owning clones, or making them. ViaGen works with a variety of contractors, which it calls “production partners,” to source oocytes and surrogate females for the animals they clone, but aside from Veneklasen, most prefer to remain anonymous. “They’re a little nervous about maybe being associated with us,” Russell, the CEO, said. Many scientists who work with clones withhold the location of their facilities out of concern that they will be targeted by animal-rights activists. ViaGen does the same with the kennels where it keeps cloned pets, Russell told me, fearing “sabotage.”
A Gallup survey from 2023, the most recent year for which data are available, found that 61 percent of Americans considered animal cloning “morally wrong”—a number that has held steady over the past two decades, even as the technology has progressed. Enabling a mortal creature to be born anew, ad infinitum, seems to some like human overreach, and cloning can involve biological tinkering that feels unsettling. In 2002, researchers tried to clone giant pandas by injecting their genetic material into rabbit oocytes, which they then implanted into a cat. (It didn’t work.) Even the more pedestrian cloning procedures often jumble breeds together in a way that lends birth a jack-in-the-box quality, as if anything might come out. To keep up with demand, ViaGen will regularly put several dog embryos from multiple clients into a single surrogate—meaning that, as a ViaGen employee told Wired last year, a beagle could theoretically “give birth to a litter of a cloned Chihuahua, a cloned Yorkie, a cloned miniature pinscher.”
And that’s when everything goes as hoped. Opponents of cloning object that it does not reliably produce healthy animals. ViaGen doesn’t publish its data on the grounds that doing so would reveal proprietary information. Russell did tell me that 60 to 70 percent of ViaGen’s cloned horse embryos will, after being transferred, result in a pregnancy—a success rate on par with the industry standard for regular embryo transfers. Yet cloned mammals that make it to term have been born with enlarged tongues, abnormal kidneys, overdeveloped muscles, defective hearts, and malformed brains, among other ailments. Kheiron, an Argentine company that clones horses, told Vanity Fair in 2015 that a quarter of its foals suffered from “serious or fatal health issues.”
Veneklasen told me that in the early days of cloning, he’d seen problems along these lines. “Fifteen years ago, it was hell,” he said. “They had big umbilical cords. And, some, they were contracted”—meaning the tendons of foals’ legs were unable to fully extend. But in the past decade, he said, “I haven’t seen any of that.” A 2016 study of 13 cloned sheep, including four Dolly clones, found them all aging normally. The latest evidence suggests that if a clone is born healthy, it will live as long and as well as any regular peer.
These days, cloning works well enough that companies often wind up with more animals than they need. Scientists’ inability to predict exactly how many embryos will make it, paired with customers’ impatience to get the animal they ordered, can lead to the implantation of extra embryos—say, six to eight to get a single puppy. At ViaGen, these “overproduction animals” will be offered at a discount to the client or adopted by an employee, Russell said. (A ViaGen spokesperson stressed that the company does not euthanize extra clones.)
Even if a clone is born healthy, other animals can suffer along the way. To create the first cloned dog, in 2005, South Korean researchers extracted eggs from dozens of females, then surgically implanted 1,095 embryos into 123 dogs—yielding only two cloned puppies, one of which died of pneumonia shortly after birth. The process has since become more efficient, but harvesting oocytes and transferring embryos to dogs’ wombs still requires them to undergo surgery.
In a paddock a short walk away from the frozen embryos, Veneklasen kept nearly 60 “recipient mares”—“recips” for short—which kicked up dust and nuzzled the dirt while they waited to have eggs removed, embryos implanted, or foals delivered. I watched one of Veneklasen’s twin colleagues, with the efficiency of a line cook, ultrasound several dozen horses to monitor gestating clones or check mares’ ovulation cycles, which the clinic controls with hormone injections that bring them into heat more quickly than usual so they can carry more foals.
Veneklasen argues that cloning is “zero inhumane.” Almost all of his recips are rescues, he told me—mostly quarter horses that didn’t work out as mounts and, instead of being slaughtered across the border (the practice is effectively illegal in the U.S.), have been conscripted into a life of perpetual reproduction. “She’s had 13 babies, and we just put them”—new embryos—“right back in,” he said, pointing to a 22-year-old mare.
The surrogates are indisputably seen as more disposable than the clones they carry. One of the twins, Hannah Looman, described rescuing a clone by performing a C-section on a pregnant recip, which died from the surgery. “Unfortunately, the clone is going to be way more valuable than the mare, so we’ve got to focus on saving the clone first,” she told me.
The mares I saw at Veneklasen’s clinic had glossy coats and well-nourished flanks. Besides being healthy, a recip’s key qualification is to be “just sweet,” Veneklasen said. ViaGen’s dog and cat surrogates, which include a range of breeds to accommodate offspring of varying sizes, are generally not rescues, but are specifically bred to be “docile,” with good maternal instincts, Russell told me. (The company gets cat oocytes from spay clinics it sponsors, and buys dog eggs from vets and breeders.)
Cloning has sparked fears that we could copy our way to a dangerously limited gene pool. But ViaGen has actually experimented with using the process to reintroduce genetic diversity into inbred populations of endangered species, such as the black-footed ferret. A female ferret’s cells were frozen at the San Diego Zoo after her death in 1988. Later, she was cloned; one of her clones was mated to a male and, in November, birthed two healthy kits. The endangered Przewalski’s horse that Veneklasen helped ViaGen clone has yielded two colts—both copies of a stallion born in 1975—that will be bred with mares at the San Diego Zoo. Other labs have cloned rare species such as gaur and bantengs.
As if to settle the question of clones’ well-being, Veneklasen brought me over to see the two recently delivered foals, both less than 48 hours old, that had been cloned from a bucking horse buried not far from the recips’ pasture. A clone’s markings can differ slightly from the original’s because of the way pigmented skin cells develop in utero, and the younger colt has a white star on its forehead that its predecessor did not. Hannah Looman and her identical twin—both with long, dark hair and wearing matching jeans with zippered vests over long-sleeved shirts—sat cuddling the younger newborn in its stall. “People get really freaked out by cloning, but you just have to say to them, ‘It’s no different than identical twins,’ ” Looman told me.
Veneklasen insists that spending time around clones is enough to convince anyone of cloning’s merits. “I mean, all you have to do is go outside and start petting animals,” he told me. “And everybody’s like, ‘Man, this is cooler than heck! That horse has been dead for five years, and yet, there he is.’ ”
Leslie Butzer cloned her first horse six years ago, but she’s been a reproduction enthusiast for much longer. She has six children, about 40 or 50 horses (“I don’t count or I have to tell my husband”), and three stables, where she’s constantly striving to breed “the best ponies in the country”—a goal she reiterated to me four times. “People call me ‘Mother Earth,’ ” Butzer told me by phone from her home in Florida. “I like to breed myself. I like to breed ponies.”
Breeders have long intervened in the process of natural selection, deliberately mating animals to ensure that their offspring can produce more milk or fit into our purses. But even the most carefully orchestrated pairing yields a genetic unknown, whereas cloning guarantees an exact replica of a top animal. This has made it an enticing tool for professional breeders, and cloning firms’ clients range from family farms to biotech companies. “Did I mention this is addicting?” one pork farmer wrote in a testimonial for Trans Ova, the livestock-cloning firm. Some breeders have even introduced gene editing in an effort to further upgrade their animals—manipulating bovine DNA, for example, to make drought-resistant cows. This process makes use of the same technology developed for cloning, although here the oocyte’s genetic material is replaced with cells from an animal whose DNA has been modified for desirable traits.
Butzer’s husband and daughter, who are both vets, have helped numerous clients clone their pets, but Butzer first got interested in using the technology herself after striking up a conversation with a ViaGen employee at a veterinary conference. Soon after, she called Blake Russell to discuss her exceptional pony Rico Suave. Then 18, solidly middle-aged in equine years, Rico was clever, athletic, and sound—everything Butzer wanted in a horse. Ponies of this caliber can be leased for as much as $250,000 a year, and in the decade that she’d owned him, Butzer had made about $2 million leasing him to riders, including the Bloomberg family. Rico’s only shortcomings: He was mortal and had no testicles.
Like most stallions, Rico had been castrated to make him more docile. But because cloning replicates only what’s encoded in DNA—and none of the physical changes an animal experiences post-birth—Rico Suave II was born fully intact and is, at age four, a father of three with two more on the way. Even now, this strikes Veneklasen as something of a magic trick: “Sperm from a gelding!” he hooted as we watched the ungelded clone of a castrated horse ejaculate into a plastic sleeve held by one of the identical twins. (Some equestrian disciplines, such as thoroughbred racing, do not allow clones to compete; others, such as rodeo, show jumping, and polo, have embraced the practice.)
Far more livestock than pets are cloned annually, and for reasons more practical than sentimental. The FDA approved the sale of meat and milk from clones in 2008, though cloned livestock are typically born to be bred, not slaughtered; their value lies in propagating their genes. Take Apple, a copper-colored Holstein with an imperious pout and a mammary system of near-bouncy-castle proportions. Mike Deaver, a former dairy farmer, told me he became “completely obsessed” with Apple after seeing the then-two-year-old heifer at a nearby farm in Wisconsin in 2006. Deaver recalled having less than $1,000 at the time, but he scraped together $60,000—an astronomical sum for such a young heifer—to buy her. Within a few months, he had skin samples taken so he could get her cloned.
Apple quickly distinguished herself: She was unusually fit, produced as much milk as top cows, and, at the 2011 World Dairy Expo, won Grand Champion in her division, a prize that recognizes the best genetics in a breed. With Trans Ova, Deaver made nine clones of Apple, essentially stockpiling her DNA. Then he began selling the genetic material to dairy farmers. They bought offspring ($190,000 for Apple’s first heifer), clones (as much as $50,000 each), and semen from her bull calves (which, at $50 a straw, brought in about $3 million). Apple now has descendants in more than 100 countries. “I’m going to say she generated us $10 million,” Deaver said. Apple’s genetics were so impressive that at the 2013 World Dairy Expo, one of her clones took the top award, Apple came in second, and Apple’s daughter placed third.
Thanks to cloning, an exceptional creature’s genetics are no longer in short supply—“We make the irreplaceable animals replaceable” is a Trans Ova sales pitch—and this has complicated the issue of who owns what. “With five minutes with a horse in the stall, I could get enough DNA to have it cloned,” simply by slicing off some of its skin, one breeder and ViaGen client told me. Cambiaso, the polo player, sued a former business partner, alleging that he’d violated their agreement to make “limited first-edition clones” of Cambiaso’s top horse by selling “unauthorized” copies to competitors. Cambiaso argued that this constituted a misappropriation of his trade secrets. After a jury sided with Cambiaso, a judge required the business partner to return every clone, as well as all the tissue samples that had been used to make them.
En route to Blake Russell’s ranch, a 1,000-acre property near Whitesboro that includes multiple air-conditioned barns for the comfort of cloned foals, Russell pulled over beside a fenced-in field and hopped out. “Let me show you something cool,” he said.
Inside the pasture were seven clones of the same mare, all two years old or younger and being kept for a polo client. The chocolate-brown fillies looked so similar, it felt like a trick of the eye, although it was their behavior that caught me off guard. Instead of scattering around the meadow, they all grazed in a clump, and when they saw us walking through the pasture, they trotted over, moving in unison like a murmuration of starlings. Each one explored me in the same affable way as they took turns sniffing my sneakers, notebook, and hair. All seven trailed us back to the car.
To many of ViaGen’s clients, cloning is appealing because of the potential they see to replicate an animal’s physical and mental makeup. ViaGen’s website assures customers that a clone can share the original’s temperament and intelligence. But some people have come to believe that clones get even more from the founder animal than that: They theorize that past experiences can be recorded in an organism’s cells through a process they refer to as “cellular memory,” and transmitted just like eye color. “There’s not a scientist in the world who will agree with me, except that I’ve seen it,” Veneklasen said.
The cloning community abounds in anecdotes: six-month-old puppies that supposedly complete agility courses as well as a five-year-old dog would; horses with the founder animal’s same fear of garden hoses or antipathy toward men. ViaGen studiously avoids making promises about cellular memory, which remains firmly a theory. Only a handful of studies have compared the behavior of clones with more traditionally bred animals, and these have found negligible differences. A 2003 paper that analyzed nine cloned pigs found that their habits and preferences varied as much as—and in some cases more than—those of eight naturally bred pigs. To what degree anyone’s behavior is shaped by genetics versus other factors continues to be a mystery, one I couldn’t help thinking of as I watched the identical twins at Veneklasen’s clinic doing their rounds. “It is funny: We both ended up doing the same thing,” Looman told me. “I don’t think we would’ve thought that.”
When a beloved horse dies, Veneklasen said, he and his twin colleagues “always tell each other, ‘She’ll be back.’ ” Our tendency to project a consistency of behavior onto copied creatures speaks to what people are eager to see in them: that they are the animal we treasured, back again for another round at life. A clone can’t resurrect the original. But in a way, it can ensure that the original never dies. “Really and truly, a horse can be alive forever. Forever and ever,” Veneklasen told me. It’s hard not to wonder whether we will turn that technology on ourselves.
In 2014, a team of researchers in California removed skin cells from a 75-year-old man, implanted his DNA into four dozen oocytes taken from human egg donors, and successfully created a cloned human embryo that developed into stem cells—the precursor to a fully fledged fetus. Neither that embryo nor several others that were made were transferred into a womb; the hope is that the technology could one day be used to, say, grow you a new kidney in a lab. But human cloning is no longer such a hypothetical.
Russell told me that ViaGen has been approached by people keen to explore it. But, he said, “we try to make it very clear our door is not even cracked open for that discussion.”
More than 80 percent of Americans consider human cloning “morally wrong,” although 12 percent now approve of it—a number that has ticked up over the past two decades. Some proponents argue that in the interest of discovery and progress, science should never be hemmed in. But from the moment Dolly the sheep was unveiled, cloning has rattled people’s faith in scientists to self-regulate. “I’m trying to think of any single announcement short of the atomic bomb that made people as nervous,” a bioethicist told me.
Certainly, the risk of public condemnation hasn’t been enough to prevent some determined individuals from experimenting with human cloning. At least four different people or groups have, since the early 2000s, claimed to be working toward the goal. These include one of the senior-most leaders of a cult, an Italian physician sentenced to prison for drugging a nurse and harvesting her eggs, and a South Korean scientist who faked data and was convicted of embezzlement and ethics violations in a case that revealed women had been paid to donate their eggs for his experiments. None of them, as far as we know, has succeeded in copying a person.
But what’s actually stopping anybody from trying to clone themselves or someone else? In the United States, human cloning is legal at the federal level. Although some states outlaw the practice, more than two dozen others, including Texas, Florida, and Pennsylvania, have no prohibitions. The U.S. government does not allow the use of federal dollars for human cloning. But given the appetite for immortality among Silicon Valley elites and others, private funding might be relatively easy to come by. “You don’t need that much to try human cloning,” says Hank Greely, the director of the Center for Law and the Biosciences at Stanford University. “You need an IVF clinic, basically, and a small lab.” (He added that it would be “deeply wrong and unethical” to attempt it.)
I spoke with one physician who remains eager to give it a go. Panayiotis Zavos, a fertility doctor in Kentucky, claimed in 2009 that a human clone was forthcoming: He said he had, at an undisclosed location, implanted 11 cloned human embryos into the wombs of four women. Whether he really did this is unclear; no babies were born. Though he is not actively pursuing cloning research now, Zavos told me, he’s still interested in copying a person. He wouldn’t say what he would need to restart his efforts, for fear of being inundated with requests. “The activity can be turned on by a switch by tomorrow, if need be,” he said. Only a few hours before we spoke, he said, he’d received a call from a German woman dying of liver cancer who was curious to explore whether she could twin herself and leave her clone her fortune. That, or harvest its liver.
This article appears in the July 2025 print edition with the headline “The Clones Are Here.”