The ethics of preimplantation genetic diagnosis

Abstract

Preimplantation genetic diagnosis is a technique used in the field of assisted reproduction. The technique is applied to embryos that have been created in vitro, in order to facilitate the selection of embryos according to particular genetic parameters. The use of preimplantation genetic diagnosis by prospective parents at high risk for having a child affected by a genetic disorder has facilitated the birth of unaffected children. Preimplantation genetic diagnosis has already been used for other purposes, such as screening for gender, and could in principle be used to screen for a wide range of genetic traits. The aim of this thesis is to provide good answers to the ethical questions provoked by the advent and continuing development of preimplantation genetic diagnosis. 
 The thesis is divided into four parts. Part One provides a brief overview of the science of genetic selection. Part Two is centred on a discussion of two ethical principles. The principle of procreative liberty is based upon the idea that acts of interference in the reproductive lives of others should be avoided unless there is good justification for such acts. The principle of procreative beneficence is based upon the idea that prospective parents should select the child, of the possible children they could have, who is expected to have the best life. I will argue that the principle of procreative liberty should be applied to acts of interference in individuals’ freedom to use preimplantation genetic diagnosis, while the principle of procreative beneficence should be applied to acts of selecting children. 
 In Part Three, I will endorse a position that accords embryos a relatively low moral status, reject the arguments of the disability rights critique, argue that the eugenic aspects of preimplantation genetic diagnosis do not warrant much concern, and develop a framework for critically evaluating slippery slope arguments. Finally, in Part Four, specific applications of preimplantation genetic diagnosis will be examined in detail. Although each application raises unique ethical questions, this thesis aims to demonstrate that the consistent application of the principles and preliminary conclusions developed in Parts Two and Three provides the best means for determining how PGD should be used and which uses should be restricted.