Prospect of Human Cloning Gives Birth to Volatile Issues
The historic announcement last week that scientists in Scotland cloned a sheep has aroused worldwide fears that people will someday be duplicated the same way. But it does not faze Charles Robinson, who already has a genetic duplicate.
“I’m not worried about cloning in the least,” said the 31-year-old computer consultant in Minneapolis. He has an identical twin, John, a human resources specialist in, of course, St. Paul, the other Twin City. “Even though John and I were born at exactly the same time, in the same family, and grew up together, there is no doubt in my mind that he and I are unique individuals.”
Naturally, John Robinson concurs. “I don’t regard my brother as an exact copy of myself,” he said. “He’s very different from me.”
As identical twins reared together, the Robinson brothers are nature’s virtual clones, and yet their point of view has been largely overlooked in the current outbreak of clone mania. Contrary to many prominent and ordinary singletons (as non-twins are sometimes called), they do not believe that cloning people would undermine the cherished human trait of individuality.
That alarm was sounded most notably by ethicist Daniel Callahan, founder of the Hastings Center in New York, who wrote that human cloning represented “a profound threat to what might be called the right to our own identity.”
To be sure, experts and lay people have expressed a variety of objections to the new reality of cloning animals as well as the still-hypothetical notion of cloning people.
* Biologists wondered if the DNA from an aged donor would give rise to a clone with a brand-new lease on life--or one that was already old, a sort of newborn oldster.
* Philosophers grappled with the hypothetical dilemma of parents wanting to clone a dying child.
* Commentators strained to point out that even a clone would have to be born, meaning that any evil genius hoping to start a basketball team of Michael Jordans would first have to raise them.
* Legal scholars tried to calm anxiety by pointing out that armies of mindlessly obedient worker-clones would be flatly illegal, given the Constitution’s prohibition against slavery.
* The director of the National Institutes of Health called the prospect of human cloning “repugnant,” a view shared by the pope.
The Humane Society of the United States cautioned that cloned farm animals would suffer pain and disability. Bernard Rollin, a philosopher at Colorado State University and author of “The Frankenstein Syndrome,” a 1995 book on issues raised by genetic engineering of animals, worried about disease resistance. Herds composed of animals with identical genetic stock are more susceptible to a range of infectious agents, he said, because their genetically determined disease defenses are limited. “I’m very concerned about untoward effects in these animals,” he said.
Long Anticipated, but Still Startling
Few biomedical researchers could remember when they had been more taken aback by a scientific advance.
“It’s been cloning hell around here,” Barbara Koenig, executive director of Stanford University’s Center for Biomedical Ethics, said of her staff’s scramble to make sense of the new research.
Still, it is hard to recall a biotechnology advance that has been anticipated for so long. Scholars say that public reaction to word of the first cloned animal has been conditioned by decades of apocalyptic science fiction about human clones waging war or doing the elite’s drudgery. Also creating more heat than light have been numerous scientific false starts played up by the news media and at least one downright hoax peddled as fact.
At the dawn of genetic engineering in the 1970s, a handful of philosophers warned of the possibility of human cloning. They lamented that the technique would strip humanity of what little mystery and wonder remained. But, philosophers say, their warnings went unheeded because they were voiced too soon or because scientists seldom pay attention to philosophers anyway.
So it is almost a relief, some researchers said, that the long-dreaded age of cloning has finally arrived, the better to look it directly in the eyes. Caleb Finch, the noted USC biologist and expert on aging, recalls that the possibility of cloning animals was discussed when he was an undergraduate in 1959. “It was fascinating to entertain the idea then,” he said. “And now here it is!”
The bleating symbol of the new and yet long-awaited Age of Cloning is the 7-month-old lamb named Dolly, born to a surrogate ewe at the Roslin Institute, a private agriculture research station outside Edinburgh, Scotland. Essentially, Ian Wilmut and his colleagues bypassed the usual mode of sexual reproduction--where sperm and egg unite to form an embryo blending the DNA from father and mother--and created a viable embryo out of an ordinary body cell, in this case from a ewe’s udder.
After growing the udder cells in a laboratory dish, they inserted one into a sheep egg cell that had its own DNA taken out. That “embryo” was then implanted in a ewe and brought to term. In the end, Dolly had the same genetic makeup of not the surrogate mother, but the ewe that donated the udder cell: Dolly was a “clone” of that ewe, conveying both the notion of identical genetic material and being produced without male-female sex.
(In contrast, identical twins, while they have the same genetic material, arise when an embryo produced by the sexual union of sperm and egg splits in half, giving rise to identical embryos.)
Wilmut has said that the purpose of the cloning experiment was to develop a technique for copying prize livestock specimens. Moreover, it sets the stage for more precisely manipulating the traits of some breeds, because cells growing in a lab dish prior to being inserted into the specialized egg might be amenable to genetic engineering, Wilmut said.
Assuming that the right DNA was available, such a cell could be supplemented with the DNA, conferring a trait--disease resistance, say--that was not present in the donor animal. In that sense, the resulting animal would not be a pure clone after all.
When asked about the possibility of human cloning, Wilmut told interviewers that he did not know of a biological reason it would not work. Still, he said in a statement: “We can see no clinical reason why that should be attempted,” adding that in the United Kingdom such experiments are prohibited.
Numerous groups have expressed trepidation at the mere thought of human cloning. And the fact that Dolly was born without any involvement from a ram foretells possible new reproductive arrangements. “Only one parent!” said the usually unflappable George Annas, a professor of health law at Boston University. “That’s new! It’s never been possible in the history of the world.”
Indeed, the prospect gives brave new plausibility to erasing men from the baby equation. On a more practical level, it would lead to new reproductive opportunities and dilemmas.
Koenig, of Stanford, posited the scenario of a lesbian couple who wanted to conceive without male involvement. One woman could donate the progenitor cell, which would then be inserted into an egg from the other, implanted, and brought to term. The daughter would give new meaning to the old war cry “sisterhood is powerful.”
Perhaps the most frequently invoked cloning scenario meant to stir the ethical juices involves a young boy, hit by lightning and surely about to die. Add parents who can no longer conceive, and the question of whether they should be able to use one of the boy’s cells to clone another son becomes genuinely troublesome to many.
Ruth Macklin, a bioethics professor at the Albert Einstein College of Medicine in New York City, disagrees with those who say such parents would be basically evil for considering such action. In fact, she said, some parents now have children for reasons that are not unequivocally benign or in the children’s best interest. But American society has generally deemed that choice private and not to be interfered with.
Horror stories purveyed by science fiction movies and novels (such as the cloned Hitlers of “The Boys of Brazil”) have prepared people to think only of “worst-case scenarios” involving cloning, Macklin said. “But these are not real possibilities in democratic societies of law.”
Questions About ‘Genetic Clock’
Though Dolly the sheep appears to be a healthy copy of the original, scientists have grave questions about whether the DNA-bearing cell taken from, say, a 70-year-old woman who wanted herself cloned would be suitable for cloning. Over a lifetime, said USC geneticist Norman Arnheim, DNA acquires mutations and other changes in the chemical bases strung along the chemical’s backbone. Cancer, for instance, is often the result of some acquired mutations, which is why elderly people as a rule have more cancers than youngsters do.
If a cell chosen from an older person for cloning happened to harbor a cancer-causing mutation, the newborn clone might also inherit the higher cancer risk of a septuagenarian.
Likewise, some gerontology researchers believe that human cells have only so much life in them, so to speak, and are genetically programmed to die after a certain number of divisions. This might explain some of the degenerative effects of aging.
Scientists do not know if a newborn clone would inherit the original’s genetic clock and grow old prematurely, said Dr. Sherman Elias, a geneticist and obstetrician at the Baylor College of Medicine in Houston.
Elias said that experiments to better understand cloning in animals should proceed under appropriate safeguards, but he is “hard-pressed to see any kind of indication why one would want to do cloning in humans. Until someone articulates a good rationale, we shouldn’t do it.”
Macklin argues for a “cautious approach, possibly a moratorium on human cloning until there is sufficient study of what the consequences might be.”
Unique Experiences Shape Who We Are
Similarly, a number of ethicists and researchers have taken pains to point out that, contrary to movies like “Multiplicity” in which adult clones appear instantaneously, a cloned human being would be carried in a woman’s womb and born. This simple fact has two major implications:
First, the baby would come into the world with the usual rights accorded a child. Far from being a robotic android or replicant generated by a baby-vending machine, it would presumably fall under the mother’s spell in the womb, subjected for months to her hormone surges and tastes in music and food. The experience would likely engender strong ties between child and mother, even if she were a surrogate, researchers say.
“The child would have all the dignity of a normal human being,” said Macklin, author of the 1994 book “Surrogates and Other Mothers.”
Second, a cloned newborn would be at least a generation removed from the original (assuming the donor cell came from an adult). That means that the clone, even though it had the same genetic makeup as the donor, would be exposed to a world of different experiences, growing into a distinct person.
Indeed, researchers say that identical twins reared together, who develop in the same womb and grow up in the same household at the same time, are more like one another than clones would be. “A lot of the similarity between identical twins is cultural,” said Julia Bailey, a genetic epidemiologist at UCLA Medical Center.
“The environment can work in ways to make even genetically identical people somewhat different from one another,” said twin researcher Nancy Segal of Cal State Fullerton.
“It doesn’t scare me that we can now clone sheep, because I don’t think the cloning of human beings would result in identical persons,” said psychologist Niels Waller, a UC Davis twin specialist.
However, Gilia Angell, a 23-year-old identical twin in Seattle, said, “I feel threatened by the prospect of human cloning because it is tinkering with nature, even if it seeks to ‘improve’ it.”
At Twins Restaurant in New York, where the staff consists of 30 pairs of identical twins, half-owner Lisa Ganz, 29, wasn’t worried about the possibility, or even likelihood, of human cloning.
“For me, it’s not a threat, because I’m already a clone. I’m the closest thing in the world to a clone. It’s wonderful.”
And yet, she says of her identical twin, Debbie, “When you look at us you see the same person, but I don’t think I look like her. I feel that we’re two very different individuals.”
Disregarding the paradox of identical twins agreeing that they are not alike, Debbie said the same thing.
* MONKEYS CLONED: Oregon researchers report success in cloning monkeys from embryos. A27
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Making a Genetic Duplicate
Nature’s Way
Twins: An egg and a sperm each have only half a set of DNA. They fuse and join their DNA as a blueprint for an organism. Sometimes the embryo divides in half, creating identical twins.
Science’s Way
Cloning: A parent cell containing a full set of DNA is inserted into an egg from which the DNA-containing nucleus has been removed. The parental DNA is then fused into the egg with an electric current and implanted into the uterus of a surrogate ewe, where it develops into a duplicate lamb.
