Do We Have The Right to Transplant Animal Parts?
by Bruce Agnew

Parts store? An engineered pig.

Almost certainly, scientists will one day make xenotransplantation possible, by genetically engineering "humanized" animals or devising new ways to tame the human immune system, or maybe both. But once we can safely transplant animal organs into people, should we?

Xenotransplantation raises a host of ethical and practical issues. Among them: Do we have the right to take animals’ organs to save human lives? Should society have new protections against diseases that might leap from animals to people—such as requiring informed-consent not just from xenotransplant patients but also from families and associates? (See related story, "Viruses Pose Problems...")

Perhaps the most emotional question concerns the proper use of animals. This is a subset of a debate over animals in research that, in western society, traces back to the ancient Greeks. But it's getting renewed attention now both from Ph.D.-toting bioethicists and ordinary people.

On one side, proponents of "animal rights" firmly oppose xenotransplantation or, in fact, any commercial use of animals—for research, for food, or even as pets.

The most vociferous and probably largest of these groups in the United States, People for the Ethical Treatment of Animals (PETA), declares that "animals are not ours to use—for food, clothing, entertainment, or experimentation." PETA calls xenotransplantation "Frankenstein science" and in June 1999, formally asked the U.S. Food and Drug Administration (FDA) to ban all xenotransplantation experiments.

On the other side is the argument that human needs trump animal rights.

AIDS patient Jeff Getty, who underwent an experimental xenotransplantation of baboon bone marrow in 1995, contended in a 1996 letter to the Wall Street Journal, "You can’t be for AIDS, breast cancer and diabetes research and also support militant animal rights groups"—because animal research is essential to scientific progress against disease.

Most Americans seem to share that view. After all, we eat about 17 billion pounds of pork each year, and more than 142 million hogs and pigs went to market in 1997, according to the U.S. Department of Agriculture.

Australian philosopher Peter Singer condemns this attitude as "speciesism." Animals deserve "equal consideration of interests," Singer said in a 1992 speech. "Pain is pain, whatever the species of being that experiences it."

Singer, now at Princeton University, acknowledged that if forced to choose between the life of an animal and the life of a child, "it seems defensible" to choose the child. But, he went on, such a choice "reinforces the attitude that animals are just things for us to use—and this is an attitude that we should strive to change."

Singer’s is a minority view. In 1996, prestigious study groups sponsored by the U.S. National Academy of Sciences (NAS) and England’s Nuffield Council on Bioethics examined ethical and other issues raised by xenotransplantation and recommended that the research go forward. Key factors for both groups, along with most bioethicists, were animals’ phylogenetic relatedness to humans and their "sentience"—the degree to which they appear to share such human traits as intelligence, consciousness, self-awareness, ability to form intentions, and ability to feel emotions such as sympathy.

Both panels signaled opposition to the use of nonhuman primates—particularly chimpanzees—as xenotransplant donors, both because of their close relatedness to humans and for fear of driving them to extinction. But this is now a dead issue. Chimpanzees and baboons are simply not going to be used as xenotransplant donors.

"The people who think that apes and primates are going to be used as organ sources are just wrong," says Harold Vanderpool, a professor of history and the philosophy of medicine at the University of Texas Medical Branch in Galveston. "It’s not going to happen, because of the worries that we rightly have over infectious disease from primates...and also because we could decimate the entire primate population and we still wouldn’t have enough organs." But Vanderpool says primates could still be used in the short run—ethically—as researchers develop xenotransplant methodology.

The Nuffield and NAS panels found less objection to the use of other animals such as pigs. "While the pig is an animal of sufficient intelligence and sociability to make welfare considerations paramount, there is less evidence that it shares capacities with human beings to the extent that primates do," the Nuffield working group said. The NAS panel observed that most people would accept the use of pigs "because these animals are traditionally used as a source of food, are distant from humans phylogenetically, and fall much lower on the personhood scale." As bioethicist Carl Cohen of the University of Michigan has said, "One cannot coherently object to the killing of animals in biomedical investigations while continuing to eat them."

Singer would agree at least with this point. "If anyone thinks that it is wrong to attempt to use the body parts of animals for transplantation purposes, but all right to use them for breakfast, then their way of thinking has nothing in common with mine," he said.

Not everyone who is concerned about animal welfare adopts an absolutist position. The Humane Society of the United States, for example, acknowledges that "biomedical research has advanced the health of both people and animals," and recognizes that "the research community is concerned about the welfare of the animals they use," says Andrew Rowan, the Humane Society's Senior Vice President for Research, Education, and International Issues.

John McArdle, director of the Alternatives Research and Development Foundation in Eden Prairie, MN, says there’s an even better way to solve organ shortages. He contends that if the United States made a serious effort to spur organ donation, there would be sufficient human organs for transplant, except possibly kidneys. He notes that several European countries have enacted "presumed consent" laws, which make all organs available upon a person’s death unless that person or his or her survivors has objected. "A major ethical issue is, can we justify xenotransplants when we’ve got such a poor record of actually trying to get human organs?" McArdle says.

In the end, the issue boils down to the same question that arises over the use of laboratory animals. And the tradeoff is the same. "The argument," says Vanderpool, "comes down to whether we think that a responsible use of animals is ethically permissible—not an irresponsible use, but very targeted, using as few animals as possible, using pain-free methods."

"Whether that’s ethically permissible," he adds, "depends very much on whether one wants to side for better health for human beings or one is willing to say that the rights of animals trump desperate human needs on a very large scale."