Natural Acts

by David Quammen

  Missy herself died in 2002, still unitary, uncloned. But of course it isn’t too late. Her genome is on ice.

  Meanwhile, two interesting new entities were born in College Station. One was a cloned cat, the world’s first, a little domestic shorthair kitten given the name CC, standing for “copycat.” The other was Hawthorne’s present company, Genetic Savings & Clone, a for-profit operation devoted to the gene-banking of pets (in the form of frozen cells) toward the possibility of their eventual cloning. CC, created with nuclear DNA from a calico donor named Rainbow, was delivered by cesarean section just before Christmas of 2001. GSC came into being in response to popular demand.

  Alerted to the Missyplicity Project by press reports, dog and cat owners had begun contacting the A&M lab. Some were grieving over recently deceased pets; some were concerned in advance over old animals or sick ones. “We’re supposed to be focusing on research here,” Westhusin recalls thinking, “and we don’t have time to take fifteen phone calls a day and talk to these people about their pets.” The callers tended to be emotional, poorly informed, and hopeful. I buried him three days ago. Do you think there’s any chance if I go dig him up that you could get cells off him? “Um, I doubt it,” Westhusin would say. Well, the temperature up here is cold. It’s Minnesota…. Westhusin laughs pityingly, and so do I. “You want to be nice,” he says, “so you sometimes spend thirty minutes talking on the phone.” With the founding of Genetic Savings & Clone, all that grief counseling could be outsourced. Dr. Charles R. Long, another reproductive physiologist and an old friend of Westhusin’s, was hired to get the company launched. As general manager, he recruited technical staff and established a lab to work in partnership with the A&M people. Occasionally he found himself playing psychologist to prospective customers, as Westhusin had done. “The people, the overly emotional ones—many times I would quite frankly try to convince them not to make this decision,” Long says. Why? Because they were doing it for the wrong reason. “They were doing it to try to get their special animal back, and you can’t get your special animal back. There’s no such thing as resurrection. At least not in pets.” What you get is just a genetic copy, a new animal with the old DNA, “and it’s really important for people to understand that.” Chuck Long is a bright, unpretentious man with a small neat mustache, the neck of a line-backer, and huge hands. He once loved a golden retriever named Tex, but he wouldn’t have cloned the animal. A loving relationship is about discovery. He’d rather discover a new friend than try to relive life with Tex Two.

  Where do people get their misguided ideas about cloning? I ask.

  “Hollywood,” says Long.

  Half ignoring his answer, I press: Do they get them from scientists who oversell the technique or from the media?

  “From Hollywood, I think,” he repeats. “You know, crazy movies like Arnold Schwarzenegger’s The 6th Day.”

  “Was he a clone in that?”

  “Yeah, they cloned him.”

  “I haven’t seen that one.”

  “You’ve got to see The 6th Day. It really stinks.”

  After a couple years at Genetic Savings & Clone, Chuck Long parted ways with Lou Hawthorne, and he now works more comfortably for a Texas company, Global Genetics and Biologicals, involved in the production and international export of elite livestock. GSC itself has severed its relationship with Texas A&M and relocated its headquarters to Sausalito, California, with offices overlooking a kayak beach.

  Genetic Savings & Clone isn’t the only company that sells a gene-banking service for pets; you might also turn to Lazaron Bio-Technologies or PerPETuate, Inc. But GSC alone offers the full deal: delivery of clonal duplicates in the near future. The initial cost of putting your pet’s genes into the gene bank is $895. Annual storage runs $100. Dogs, with their unique physiological complications (such as opacity of the eggs, making them harder to enucleate), are still problematic. But commercial cat cloning got under way in 2004, with five clients committed, and if all goes well, their cats will be delivered very soon. “In pet cloning,” says Hawthorne, “people have an animal that they perceive is extraordinary. In some cases, it’s just a perception.” In other cases, the extraordinariness is more objective. “You can have an extraordinary mutt,” he says. “You can have an animal that has extraordinary intelligence. Extraordinary good looks.” Insofar as those traits are genetic, they can be reproduced by cloning, maybe. The delivery price of a healthy young feline, custom-created from DNA of proven appeal, guaranteed to resemble your old feline closely, is $50,000. If you think this might meet your emotional expectations, act now.

  On the other hand, $50,000 buys a lot of pretty good cats.

  Cloning endangered species is a different matter. For starters, who pays? Why does anyone finance this technical approach, seemingly so marginal, rather than putting money toward basic necessities such as habitat protection? And how can cloning possibly freshen a gene pool that has been reduced to a stagnant puddle? I carry these questions to Dr. Betsy Dresser, director of the Audubon Center for Research of Endangered Species, near New Orleans. ACRES is part of the Audubon Nature Institute, a nonprofit group of museums, parks, and other facilities (with no connection to the National Audubon Society). Dresser, who ran a similar research center at the Cincinnati Zoo before coming to New Orleans, has long been a leader in applying captive-breeding efforts and assisted reproductive technologies to endangered species.

  She’s a brisk, congenial woman, but not easy to get to. ACRES is tucked away in a sunny new building surrounded by bottomland forest at the end of a country road outside the city, on the west bank of the Mississippi River, beneath a towering levee. The land, 1,200 acres of what once was sugar plantation, is protected by a fence and a guard house with an electric gate. A sign says FREE-PORT MCMORAN AUDUBON SPECIES SURVIVAL CENTER, recognizing the sponsorship of a mining company in establishing this compound. ACRES itself was created with a $15 million appropriation from the U.S. Fish and Wildlife Service. It resembles the visitor’s center of a well-funded state park, but more private. On a morning in April, the air is redolent with honeysuckle. I arrive in time to watch surgery on a domestic cat.

  Dr. C. Earle Pope, in a blue smock and mask, is harvesting ova. Several other figures, also in blue, assist him around the operating table. The cat has already been anesthetized and opened, its ovaries exposed. Pope wields a fine forceps in one hand, a hollow steel needle in the other, his head raised to view the target area as magnified on a video monitor. He works with easy skill derived from years of experience. The hollow needle is backed by a suction device that feeds into a glass vial on a table nearby. With the forceps, Pope gingerly lifts one ovary so that its follicles (the small, bulbous ovarian sacs) protrude like grapes on a bunch. With the needle, he punctures a follicle and sucks out the egg, then moves to another. The ovary bleeds slightly. Poke, suck, poke, suck, the eggs are whisked away. They accumulate in the vial. When Pope has emptied the follicles of both ovaries, an assistant collects two orange-caped vials and passes them through a window from the operating room to an adjacent lab.

  In the lab, which is darkened and barely larger than a closet, a technician moves the eggs from a rinsing solution onto a petri dish. She lifts them one by one, using an aspirator pipette—that is, with suction applied by her own gentle breath. Her eyes are pressed to a scope. The eggs, surrounded by cloudy globs of ovarian material (called cumulus cells) and air bubbles, are tiny, but they are conspicuous enough to her. You can tell the maturity of the ova, she says, by the layers of cumulus cells attached. “These are very good-looking.” The yield today is twenty-four eggs, about average from a domestic cat. Down the hall, she places the petri dish in an incubator. This afternoon one of Pope’s colleagues, Dr. Martha C. Gomez, will enucleate these eggs and endow each with nuclear DNA transferred from an African wildcat.

  It won’t be the first time such a mix is performed. The Africa wildcat, Felis silvestris lybica, is a tawny little felid native to Africa and the Middle Eas
t, related to the domestic cat, Felis silvestris catus, closely enough to have figured in earlier experiments involving the two subspecies. Using domestic cat eggs, Gomez, Pope, and their team produced three Africa wildcat clones in 2003, the eldest born on August 6 and named Ditteaux. (That’s ditto with Cajun spicing.) The animal from which he and his…his what? not siblings, not twins—his two extremely close relatives were cloned, known as Jazz, was itself a product of combined ARTs: the world’s first frozen-embryo, thawed-embryo, embryo-transferred wildcat born to a domestic cat. Gomez, Dresser, Pope, and several colleagues coauthored a journal paper on this work, in which they note that the African wildcat “is one of the smallest wild cats, whose future is threatened by hybridization with domestic cats.” A person might ask: If hybridization of a wild subspecies with a domestic subspecies is the threat, in what sense is mixing nuclei from one subspecies with eggs from the other subspecies a solution?

  Another skeptical question, which I put to Betsy Dresser, is whether this fancy stuff can somehow mitigate the problem of low genetic diversity in sorely endangered species. If it can’t, what’s the point? “Well, indeed it can,” Dresser says. “What we’re trying to do is use cloning to bring in the genetic material from animals that are not reproducing.” Among any population, she says, there are always infertile individuals, marginalized individuals, elderly or unlucky individuals, who fail to breed and so contribute no genes to the next generation. In a large population (though Dresser doesn’t mention this point), their exclusion represents Darwinian selection, which drives evolution. But in a very small population (she notes rightly), their participation could be crucial. “If you can use the genetic material from those individuals, it helps widen the genetic pool a bit.”

  Imagine you’ve got a captive population of just five black-footed ferrets, with no others surviving on the planet. Four of your ferrets are males and the fifth is a postreproductive female. One young male chokes to death while eating a prairie dog with reckless gusto. What do you do? Of course you grab the old female and the dead male, take tissue samples, and clone them. But wait—in this scenario of five, there are no viable black-footed ferret ova to receive the clonal DNA. So you use the next best thing: enucleated eggs from a mink. Then you breed your cloned female with one of the males, breed any daughters she produces with other males, get the cloned male’s genes into the reproductive jumble too, and thereby postpone (maybe indefinitely) the doom of your miserable little population. Whether your ferrets ever go back into the wild is another question. Do you dare send them? Do you keep breeding and cloning until you’ve got a few dozen, a few hundred? All this would be expensive at best and, if you hadn’t meanwhile solved the root causes of endangerment (such as insufficient habitat, government-sponsored poisoning of prairie dogs, poaching, or exotic species inflicting too much predation or competition), ultimately futile. No clones of an endangered species, and no descendants of clones, have ever yet been released to the wild.*

  What about the money issue? I ask Dresser. Are resources being diverted that might otherwise pay for habitat preservation? Her answer is candid: “The money that comes to this kind of research is primarily from people that are not going to support habitat.” She’s a skilled fundraiser as well as a respected scientist; she has been through this in Cincinnati, now New Orleans, and she knows her constituency. Sponsoring the research arm of a fine metropolitan zoo is a bit like sponsoring the symphony, the conservatory, the opera. These people “don’t want to give their money to Africa, or to Asia, or somewhere. They don’t want their money in political environments where they’re never going to see their name on a plaque.” At the various branches of the Audubon Nature Institute, including ACRES, there are more than a few grateful plaques.

  Back on the city side of the river, I visit the Audubon Zoo on Magazine Street for a glimpse of Ditteaux the cloned wildcat, temporarily on display there. For this interlude of public exposure, he lives in a glass-fronted cage furnished with small boulders, trees, and a six-foot square of scenery meant to approximate northern Africa. He’s a handsome animal, lanky and lithe, nervous, his brownish gray fur marked with pale stripes. As I watch, his pale green eyes come alert to something—the sight of a squirrel outside the building, visible through an opposite window.

  Groups of schoolchildren pass Ditteaux’s cage. A well-fed boy in an orange T-shirt reads the sign and then asks, “It’s a clone?” Yes. With some vehemence, he says, “Okay, that’s freaky.”

  Whatever the downside of investing money and time in such an approach to endangered species, at least one private firm has also done it: Advanced Cell Technology, of Worcester, Massachusetts. Founded originally as a subsidiary of a poultry genetics business, ACT now concentrates mainly on human and medical issues. The company’s work with wildlife is an adventuresome sideline, bearing no such commercial promise as cloning whitetail deer for the trophy market but offering the possibility of a public good, roughly equivalent to pro bono work by a law firm. It also offers, when successful, good publicity.

  In early 2001, ACT announced that “the first cloned endangered animal,” an eighty-pound male gaur, had been born to a surrogate mother. The gaur is a species of wild cattle, Bos gaurus, native to southeastern Asia from Thailand to Nepal. Calling it an “endangered animal” was mildly misleading; the international body that keeps track of such things classifies the gaur as “vulnerable,” not actually “endangered,” with somewhere between 13,000 and 30,000 individuals in the wild. But the population is declining, and the trend isn’t likely to reverse. Vulnerable or endangered, the species deserves attention.

  Two technical points made ACT’s gaur work especially notable. First, the nuclear DNA came from gaur cells derived from a tissue sample that had sat frozen for eight years in a gene bank at the San Diego Zoo. Second, the enucleated egg cell into which the gaur DNA had been transferred came from a domestic cow. So this too was a case of cross-species cloning—in fact, it was the first recorded case, precursor to the African wildcat project in New Orleans. Arguably, the technique could be valuable in situations when egg cells of an endangered species are unavailable—when there are no surviving females, say, or so few that you wouldn’t dare cut one open to harvest her eggs.

  What made the case less encouraging was that the baby gaur, named Noah, died of dysentery within two days. Its death fell hard on Robert P. Lanza, a vice president of ACT, who had led the cloning effort.

  At that time, Lanza had nearly sealed an agreement with Spanish officials toward cloning an extinct Spanish subspecies of mountain goat, the bucardo. The bucardo (Capra pyrenaica pyrenaica) had languished at desperately low population levels throughout the twentieth century, probably because of competition with livestock, diseases caught from livestock, poaching, and other travails. The last one died in 2000, clunked by a falling tree, but provident biologists had arranged to freeze some of its tissue for posterity. Lanza hoped to clone the bucardo back into existence, using the frozen sample for nuclear DNA, a domestic nanny goat as egg donor, and a nanny again as surrogate to carry the fetus. That plan collapsed with the death of Noah the gaur. Two years later ACT’s cloning team tried again, this time achieving the birth of two cloned calves from another species of wild Asian cattle, the banteng, Bos javanicus. The banteng is unambiguously endangered, with no more than 8,000 individuals in the wild. The nuclear DNA came from another frozen sample that had been stored, for twenty-five years, at the San Diego Zoo.

  The gene bank in San Diego, loosely known as the Frozen Zoo, was established three decades ago by a pathologist named Kirk Benirschke, who was soon joined by a young geneticist, Oliver A. Ryder. Benirschke and Ryder foresaw that these cell samples might be useful in genetic studies of relatedness among wild species. They didn’t foresee that the frozen cells might be cloned back to life. The collection now represents about 7,000 individual animals of 450 different species; about half of those samples came from creatures resident at the San Diego Zoo, the rest from other zoos and captiv
e facilities, or from the wild. Ryder is still there, the man to see if you want a morsel of rare or endangered DNA for some legitimate purpose. Cloners across the country, from College Station to Worcester and beyond, point to San Diego’s Frozen Zoo as a prescient enterprise that should be emulated widely, preserving as much genetic diversity as possible from endangered species before their populations decline too far. Ryder, for his part, supports the idea of cloning when it might return a valuable genotype to a breeding population. The original banteng whose frozen cells went to ACT, for instance, died in 1980 without offspring, having made no genetic contribution to the captive banteng population. One of the two clones produced from those cells was healthy, and that animal has since been returned to San Diego; its lost genes may eventually be bred back into the zoo population of banteng, possibly adding some much-needed diversity.

  But gene banking is no panacea. Ryder himself says: “I think it’s gonna be a somber day when we realize that the only thing left of a species is something we’ve got in the Frozen Zoo.”

  Among extinct species and subspecies, the bucardo goat represents a good prospect for cloning, because the extinction is so recent and the cell sample was properly preserved. Less propitious circumstances, though, don’t prevent people from trying to resurrect a lost beast.

  Scientists at Kinki University in Japan have begun work toward cloning a woolly mammoth, using tissue samples from a 20,000-year-old carcass recently excavated from frozen Siberian tundra. Elephants, the mammoth’s closest living relatives, will serve as egg donors and surrogate mothers, if the project ever gets that far. Cloning researchers at the Australian Museum in Sydney hope to recreate the thylacine, a carnivorous marsupial loosely known as the Tasmanian tiger, last seen alive in 1936. For that effort, the starting point is a thylacine pup stored in alcohol since 1866. Alcohol is a gentler preservative than formaldehyde, and the Australians have managed to extract some DNA fragments in fairly good condition—but no complete DNA strands, let alone any viable thylacine cells with nuclei that could be transferred intact. The optimistic Aussies aim to reassemble their squibs and scraps into a full set of thylacine DNA, perhaps patching the gaps with genetic material from other marsupials. Plausible? Not very, according to Ryder. “What’s the chance that you could shred the phone book,” he asks, “and then drop it out of a window and have it come back together?” Once they have reassembled their phone book, if they do, the Australians will create artificial chromosomes for insertion into an egg from some related species, such as the Tasmanian devil. Meanwhile, in Hyderabad, India, a team led by Dr. Lalji Singh proposes to clone an Asiatic cheetah, a subspecies extinct in India for the past fifty years. They want to use nuclear DNA from a cheetah loaned by Iran, though Iran itself has only a few dozen cheetahs in the wild, and none of those has been promised so far. If the Indians do get their chance to proceed, the eggs and the surrogate wombs will be furnished by leopards.