The seductive sirens of medical progress. The case of xenotransplantation.

Each new announcement of advancement on the front of medical progress calls forth a sense of hope, even urgency. What sickness might soon be cured? Whose lives might be saved? What critical knowledge might be gained? That medicine will continue to progress in these struggles is something in which people have tremendous faith. The arguments in favor of developing any emerging medical technology are therefore especially powerful and seductive. They are rarely denied. In fact, it is almost heresy to try. But the seduction of medical progress has the power easily to tip the balance of careful public policy considerations. A recent Institute of Medicine conference on xenotransplantation (25-27 June 1995) illustrated nicely the kinds of arguments the medical world has rarely, if ever, been able to resist. The conference was supposed to provide an IOM committee with balanced considerations regarding this potential next step in organ transplantation. Although several persons raised cries of caution, the sirens of progress--calling us to fascinations now just beyond our reach--were sounding familiar and pleasing harmonies. In this essay I would like to identify these irresistible themes of progress, not so much to argue against them as to make them evident so that our future collective deliberations on the ethics of xenograft technologies, or any other step in medical progress, will be informed by attention to the seductions that may drown out dissension and cloud our better judgment. Scientific Uncertainty/Clinical Imminence (The "10/90 Argument"). The IOM conference began by assessing the science base for xenotransplantation. The tone was set immediately by surgeon Keith Reemtsma, who suggested that he did not know if the science was "10 percent or 90 percent" of the way toward success (left undefined), but that such uncertainty argued in favor of continued pursuit of many avenues of research, with little need for regulation at this point. The theme of significant uncertainty as a justification for research was picked up by another legend in the field, Thomas Starzl, who agreed with Reemtsma, but added, "I doubt that we're really that close. " Starzl's argument from scientific uncertainty highlighted the power of Reemtsma's 10/90 argument. From the perspective of scientific objectivity, to be only 10 percent of the way toward successful xenografts would seem to endorse a rather harmless continued pursuit of research to see if such transplants might even be possible. What could it hurt? But Starzl's argument did not escape the notice of a participant who reminded him of his statement following his failed baboon liver transplants: "It would be surprising if successful xenotransplantation [in humans] were not achieved within the next six to twelve months" (JAMA, 16 June 1993). This statement represents the "90 percent" side of the argument. When the physician is no longer the scientist but now the surgeon at the bedside, optimistic 90-percent-type arguments provide even stronger justification for moving forward with research: now that the science has progressed far enough that real lives hang in the balance, not to pursue further progress would clearly be unjustifiable. So no matter how far along the science is, the justification for pursuing it is there. Confidence in Controlling Risk. Xenotransplantation raises a whole host of risks to individual and public health. It is perhaps noteworthy that at this conference considerably less attention was paid to risks of the genetic variety, which may come from creating transgenic animals (the result of introducing the genes of one species into another). On this score, however, one scientist argued that with these genetic manipulations, "We are doing nothing different from what is already occurring in nature." In fact, she continued, nature is "more dangerous" because the genetic mutations occurring there are not controlled, as they are in the lab. …