EQUALITY AND THE TREATMENT-ENHANCEMENT DISTINCTION NILS HOLTUG Keywords equality of opportunity, the treatment-enhancement distinction, genetics ABSTRACT In From Chance to Choice, Allen Buchanan, Dan Brock, Norman Daniels and Daniel Wikler propose a new way of defending the moral significance of the distinction between genetic treatments and enhancements. They develop what they call a ‘normal function model’ of equality of opportunity and argue that it offers a ‘limited’ defence of this distinction. In this article, I critically assess their model and the support it (allegedly) provides for the treatment-enhancement distinction. First, I argue that there is a troubling tension in the normal function model. Secondly, I argue that neither of the rationales invoked by Buchanan et al. really serves to justify this model or the results they seek to derive from it with respect to the significance of the distinction between treatments and enhancements. 1. INTRODUCTION It has turned out to be surprisingly difficult to provide a principled defence of the moral significance of the distinc- tion between genetic treatments and enhancements. 1 Nev- ertheless, in From Chance to Choice, Allen Buchanan, Dan Brock, Norman Daniels and Daniel Wikler (hence- forth: Buchanan et al.) propose a new way of defending the moral relevance of the distinction. 2 They have devel- oped what they call a ‘normal function model’ of equality of opportunity and argue that it offers a ‘limited’ defence of this distinction. More specifically, they argue that the normal function model implies that although justice may often require genetic intervention to restore people with diseases and disabilities to normal functioning, in general it does not require genetic enhancements. In the current article, I want to assess critically Bucha- nan et al.’s egalitarian argument for the moral signifi- cance of the treatment-enhancement distinction. To start, however, I need to clarify the framework within which I shall conduct my discussion. First, I follow Buchanan et al. in considering genetic interventions quite generally, where such interventions include both gene therapy and genetic pharmacology. Secondly, again following Buchanan et al., I take ‘treatment’ to be an intervention that aims to cure or prevent a disease, or reduce its effects, where ‘disease’ is taken to be an adverse departure from species-typical normal functioning. 3 Enhancements, on the other hand, do not aim to cure or prevent disease, or reduce the effects thereof. Thus, enhancements may aim to affect various non-disease related factors that have a genetic component, including intelligence, talent, strength and height. Thirdly, there are obviously many moral issues to be considered in relation to genetic intervention, including 1 N. Holtug. Altering Humans – the Case for and Against Human Gene Therapy. Camb Q Healthc Ethics 1997; 2; N. Holtug. 1998. Creating and Patenting New Life Forms. In A Companion to Bioethics, P. Singer and H. Kuhse eds. Oxford: Basil Blackwell. 2 A. Buchanan et al. 2000. From Chance to Choice. Genetics and Justice. Cambridge: Cambridge University Press. 3 C. Boorse. On the Distinction between Disease and Illness. Philos Public Aff 1975; 5. Address for correspondence: Nils Holtug, Director, Centre for the Study of Equality and Multiculturalism, Philosophy Section, Department of Media, Cognition and Communication, Njalsgade 80, DK-2300 Copenhagen S, Denmark. email: nhol@hum.ku.dk Bioethics ISSN 0269-9702 (print); 1467-8519 (online) doi:10.1111/j.1467-8519.2009.01750.x Volume 25 Number 3 2011 pp 137–144 © 2009 Blackwell Publishing Ltd., 9600 Garsington Road, Oxford OX4 2DQ, UK and 350 Main Street, Malden, MA 02148, USA.