Henry I. Miller

Scientists have created a line of monkeys carrying a gene that encodes a green fluorescent protein integrated into their DNA and passed on to their offspring. The research, published this week by a group of Japanese and American scientists in the British journal Nature, marks the first such accomplishment in primates and could lead to new models of human diseases.

But this technology could, at least in theory, also be used not to prevent or treat disease but for "enhancement"--for greater intelligence or physical prowess, for example. For that reason, the just-published experiment already has revived the controversy over various ethical issues, such as whether such applications are legitimate and how they should be controlled.

But enhancement must be considered in the context of current practices with other technologies. As technology offers increasingly more extreme possibilities--such as genetic manipulation--for enhancement, one might argue that they are just the next steps along a continuum. Medicine has already made great advances in the use of cognition-enhancing drugs, which doctors prescribe to treat cognitive disabilities and improve quality of life for patients with neuropsychiatric disorders and brain injury. And one survey suggests that as many as 7% of students use stimulants such as methylphenidate (Ritalin) and modafinil (Provigil) as "smart drugs" to improve their grades.

Scientists using "gene therapy" to increase the levels of a single enzyme several years ago created a strain of mice with increased physical abilities by genetically altering a metabolism gene. These "mighty mice" run much faster and longer than their non-genetically-engineered cohorts.

These kinds of experiments have stimulated debate about the ethics of creating "designer humans." Molecular biologist Lee Silver of Princeton University has written thoughtfully about these issues. He speculates about the emergence of two biological classes, the "Gen Rich" and "Naturals." He speculates that the former, comprising perhaps 10% of the population, will include businessmen, musicians, artists, athletes and intellectuals, all of whom have all been enhanced with specific synthetic genes that allow them to perform at levels not possible for those who have access only to Nature's lottery. They might be thought of as the logical successors to A-Rod and Marion Jones, who were able to use only crude chemical means to enhance their athletic prowess. Whether or not such enhancement would be performed in a way that limits it to the subject who decides to undergo it, or would be heritable (passed on to offspring), remains to be seen.

Who, then, should dictate when and how such procedures can be used? Economist Francis Fukuyama thinks the answer is more government regulation. In Our Posthuman Future, he proposes "a new agency to oversee the approval of new medicines, procedures and technologies for human health," which would exert broader control than current regulation, by including "other societal voices that are prepared to make judgments about the technology's social and ethical implications."

This additional interference with decisions that should be left to consumers and physicians smacks of anti-libertarian nanny-statism. Moreover, it ignores the fact that our society now affords wide latitude to those who choose to enhance their appearance or health in other ways. For example, drugs are commonly tested and commercialized for relatively trivial indications, such as modest obesity, age spots and baldness. The injectable drug Botox, widely used to treat nothing more ominous than wrinkles, is one of the best-selling drugs in the U.S. There have been numerous clinical trials of appetite suppressants, memory- and performance-enhancing drugs; and human growth hormone is now FDA-approved for hormonally normal but short children.

Gene therapy--which inserts genes into a person to correct a deficiency or induce synthesis of a therapeutic substance--is an extension of drug and surgical treatments, and part of a continuum of medical interventions that introduce or modify DNA or modulate genes' activity. Among the therapies on the continuum are organ transplantation (for genetic-deficiency diseases), vaccination (which precipitates irreversible changes in white blood cells' DNA, as they initiate the synthesis of antibodies) and drugs (to stimulate the activity of dormant genes in sickle-cell anemia). It should be noted, however, that none of these interventions is passed on from the patient to succeeding generations.

Over more than half a century, physicians, ethicists, patients and society at large have had to confront the many medical and ethical questions that these interventions have raised that are similar to those of gene therapy. Issues such as whether a patient suffers from a condition that warrants treatment, the kinds and magnitude of risks, and equal access to therapy are fundamentally no different for gene therapy than for other interventions. Therefore, even when used for enhancement, gene therapy should not be treated differently from other medical interventions.

Arguments against testing gene therapy for enhancement should be weighed against society's permissiveness toward experimental medical and surgical interventions in general, and those intended for non-therapeutic purposes in particular. Patients' psychological well-being and freedom to choose also are important considerations. "Mere" enhancement is not trivial to the adolescent boy who is six inches shorter than anyone else in his class, and cosmetic surgery is extraordinarily popular.

An array of entities, at several levels of government, regulates gene therapy. This intensive and highly duplicative oversight offers a stark contrast to the scrutiny of a radical new surgical procedure, for example, which might be completely unregulated or subject only to approval of hospital-based committees.

American society already has the mechanisms in place to evaluate the medical risks and benefits of gene therapy, and individuals can be given the information they need to decide whether the personal benefits of enhancement outweigh the risks.

If society is to realize the full spectrum of benefits from human gene therapy, it cannot be considered in a philosophical vacuum. It must be judged in the broader context of what people want and what society permits.

Henry Miller, a physician and molecular biologist, is a fellow at Stanford University's Hoover Institution. From 1979 to 1994, he was an official at the FDA.