Bioethics

The positive–negative boundary may seem a way of avoiding objectionably God‐like decisions, on the basis of our own values, as to what sort of people there should be. Saving someone from spina bifida is a lot less controversial than deciding he shall be a good athlete. But the distinction, clear in some cases, is less sharp in others. With emotional states or intellectual functioning, there is an element of convention in where the boundaries of normality are drawn. And, apart from this, there is the problem of explaining why the positive–negative boundary is so much more important with genetic intervention than with environmental methods. We act environmentally to influence people in ways that go far beyond the elimination of medical defects. Homes and schools would be impoverished by attempting to restrict their influence on children to the mere prevention of physical and mental disorder. And if we are right here to cross the positive–negative boundary, encouraging children to ask questions, or to be generous and imaginative, why should crossing the same boundary for the same reasons be ruled out absolutely when the means are genetic?

1 1Chris Graham has suggested to me that it is misleading to say this without emphasizing the painful slowness of this way of changing gene frequencies.

2 2The Future of Man (The Reith Lectures, 1959), London, 1960, chapter 3; and in ‘The Genetic Improvement of Man’, in The Hope of Progress, London, 1972.

3 3Genes. Dreams and Realities, London, 1971, p. 81.

4 4‘Already they have pushed Cline’s results further, obtaining transfer between rabbit and mouse, for example, and good expression of the foreign gene in its new host. Some, by transferring the genes into the developing eggs, have managed to get the new genes into every cell in the mouse, including the sex cells; those mice have fathered offspring who also contain the foreign gene.’ Jeremy Cherfas: Man Made Life, Oxford, 1982, pp. 229–30.

5 5Out of the Night, New York. 1935. To find a distinguished geneticist talking like this after the Nazi period is not easy.

6 6John Maynard Smith: On Evolution, Edinburgh, 1972; the article is reprinted from the issue on ‘Utopia’ of Daedalus, Journal of the American Academy of Arts and Sciences, 1965.

7 7Anarchy, State and Utopia, New York, 1974, p. 315.

8 8Anarchy, State and Utopia, p. 315.

9 9This kind of unworldly innocence is part of the engaging charm of Nozick’s dotty and brilliant book.

10 10Decision‐taking by a central committee (perhaps of a dozen elderly men) can be thought of as a ‘Russian’ model. The genetic supermarket (perhaps with genotypes being sold by TV commercials) can be thought of as an ‘American’ model. The mixed system may appeal to Western European social democrats.

David B. Resnik

The therapy–enhancement distinction occupies a central place in contemporary discussions of human genetics and has been the subject of much debate. 1 – 7 At a recent conference on gene therapy policy, scientists predicted that within a few years researchers will develop techniques that can be used to enhance human traits. 8 In thinking about the morality of genetic interventions, many writers have defended somatic gene therapy, 9 , 10 and some have defended germline gene therapy, 11 , 12 but only a handful of writers defend genetic enhancement, 13 or even give it a fair hearing. 14 – 16 The mere mention of genetic enhancement makes many people cringe and brings to mind the Nazi eugenics programs, Aldous Huxley’s Brave New World , “The X‐Files,” or the recent movie “Gattaca.” Although many people believe that gene therapy has morally legitimate medical uses, 17 , 18 others regard genetic enhancement as morally problematic or decidedly evil. 19 – 21

The purpose of this essay is to examine the moral significance of the therapy–enhancement distinction in human genetics. Is genetic enhancement inherently unethical? Is genetic therapy inherently ethical? I will argue that the distinction does not mark a firm boundary between moral and immoral genetic interventions, and that genetic enhancement is not inherently immoral. To evaluate the acceptability of any particular genetic intervention, one needs to examine the relevant facts in light of moral principles. Some types of genetic therapy are morally acceptable while some types of genetic enhancement are unacceptable. In defending this view, I will discuss and evaluate several different ways of attempting to draw a solid moral line between therapy and enhancement. 22

Before discussing the therapy–enhancement distinction, it is important that we understand another distinction that should inform our discussion, viz. the distinction between somatic and germline interventions. 23 , 24 Somatic interventions attempt to modify somatic cells, while germline interventions attempt to modify germ cells. The gene therapy clinical trials that have been performed thus far have been on somatic cells. If we combine these two distinctions, we obtain four types of genetic interventions:

1 Somatic genetic therapy (SGT)

2 Germline genetic therapy (GLGT)

3 Somatic genetic enhancement (SGE)

4 Germline genetic enhancement (GLGE)

While I accept the distinction between somatic and germline interventions, it is important to note that even interventions designed to affect somatic cells can also affect germ cells: current SGT trials carry a slight risk of altering germ cells. 25 Even so, one might argue that this is a morally significant distinction because somatic interventions usually affect only the patient, while germline interventions are likely to affect future generations. 26 In any case, the therapy–enhancement distinction encompasses somatic as well as germline interventions, and my discussion of this distinction will include both somatic as well as germline interventions.

Perhaps the most popular way of thinking about the moral significance of the therapy–enhancement distinction is to argue that the aim of genetic therapy is to treat human diseases while the aim of genetic enhancement is to perform other kinds of interventions, such as altering or “improving” the human body. 27 – 29 Since genetic therapy serves morally legitimate goals, genetic therapy is morally acceptable; but since genetic enhancement serves morally questionable or illicit goals, genetic enhancement is not morally acceptable. 30 – 33 I suspect that many people view the distinction and its moral significance in precisely these terms. W. French Anderson states a clear case for the moral significance of genetic enhancement:

On medical and ethical grounds we should draw a line excluding any form of genetic engineering. We should not step over the line that delineates treatment from enhancement. 34

However, this way of thinking of medical genetics makes at least two questionable assumptions: (1) that we have a clear and uncontroversial account of health and disease, and (2) that the goal of treating diseases is morally legitimate, while other goals are not. To examine these assumptions, we need to take a quick look at discussions about the concepts of health and disease.

The bioethics literature contains a thoughtful debate about the definitions of health and disease and it is not my aim to survey that terrain here. 35 , 36 However, I will distinguish between two basic approaches to the definition of health, a value‐neutral (or descriptive) approach and a value‐laden (or normative) one. 37 According to the value‐neutral approach, health and disease are descriptive concepts that have an empirical, factual basis in human biology. Boorse defended one of the most influential descriptive approaches to health and disease: a diseased organism lacks the functional abilities of a normal member of its species. 38 To keep his approach value‐neutral, Boorse interprets “normal” in statistical terms, i.e., “normal” = “typical.” Daniels expands on Boorse’s account of disease by suggesting that natural selection can provide an account of species‐typical functions: functional abilities are traits that exist in populations because they have contributed to the reproduction and survival of organisms that possessed them. 39 Thus a human with healthy lungs has specific respiratory capacities that are normal in our species, and these capacities have been “designed” by natural selection. A human who lacks these capacities, such as someone with cystic fibrosis or emphysema, has a disease.