Should We Clone Human Beings? Cloning As
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Journal ofMedical Ethics 1999;25:87-95 J Med Ethics: first published as 10.1136/jme.25.2.87 on 1 April 1999. Downloaded from Should we clone human beings? Cloning as a source of tissue for transplantation Julian Savulescu The Murdoch Institute, Royal Children 's Hospital, Melbourne, Australia Abstract 3. It violates a person's right to genetic individu- The most publiclyjustifiable application ofhuman ality (whatever that is-identical twins cannot cloning, ifthere is one at all, is to provide have such a right). self-compatible cells or tissuesfor medical use, 4. It allows eugenic selection. especially transplantation. Some have argued that 5. It uses people as a means. this raises no new ethical issues above those raised by 6. Clones are worse off in terms of wellbeing, anyform ofembryo' experimentation. I argue that especially psychological wellbeing. this research is less morally problematic than other 7. There are safety concerns, especially an embryo research. Indeed, it is not merely morally increased risk of serious genetic malformation, permissible but morally required that we employ cancer or shortened lifespan. cloning to produce embryos orfetuses for the sake of providing cells, tissues or even organs for therapy, There are, however, a number of arguments in followed by abortion of the embryo orfetus. favour of human reproductive cloning. These (7ournal ofMedical Ethics 1999;25:87-95) include: Keywords: Cloning; transplantation; autonomy; embry- copyright. onic stem cells; fetal tissue; embryo experimentation; abor- 1. General liberty justifications. tion; potential 2. Freedom to make personal reproductive choices. 3. Freedom of scientific enquiry. Introduction 4. Achieving a sense of immortality. When news broke in 1997 that Ian Wilmut and his 5. Eugenic selection (with or without gene http://jme.bmj.com/ colleagues had successfully cloned an adult sheep, therapy/enhancement). there was an ill-informed wave of public, profes- 6. Social - sional and bureaucratic fear and rejection of the utility cloning socially important new technique. Almost universally, human clon- people. ing was condemned."4 Germany, Denmark and 7. Treatment of infertility (with or without gene Spain have legislation banning cloning; Norway, therapy/enhancement). Slovakia, Sweden and Switzerland have legislation 8. Replacement of a loved dead relative (with or implicitly banning cloning.7 Some states in without gene therapy/enhancement). on September 26, 2021 by guest. Protected Australia, such as Victoria, ban cloning. There are 9. "Insurance" - freeze a split embryo in case two bills before congress in the US which would something happens to the first: as a source of comprehensively ban it.89 There is no explicit or tissue or as replacement for the first. implicit ban on cloning in England, Greece, 10. Source of human cells or tissue. Ireland or the Netherlands, though in England the 11. Research into stem cell differentiation to Human Embryology and Fertilisation Authority, provide an understanding of aging and which issues licences for the use of embryos, has oncogenesis. indicated that it would not issue any licence for 12. Cloning to prevent a genetic disease. research into "reproductive cloning". This is understood to be cloning to produce a fetus or live The arguments against cloning have been criti- birth. Research into cloning in the first 14 days of cally examined elsewhere and I will not repeat life might be possible in England.7 them here.''" Few people have given arguments There have been several arguments given in favour of it. Exceptions include arguments in against human reproductive cloning: favour of 7-12,12 with some commentators favouring only 10-1 1 13 14 or 1 1-12.' Justifications 1. It is liable to abuse. 10-12 (and possibly 7) all regard cloning as a way 2. It violates a person's right to individuality, of treating or avoiding disease. These have autonomy, selfhood, etc. emerged as arguably the strongest justifications 88 Should we clone human beings? Cloning as a source of tissue for transplantation J Med Ethics: first published as 10.1136/jme.25.2.87 on 1 April 1999. Downloaded from for cloning. This paper examines 10 and to some person who is intended as the recipient of cell extent 1 1. therapy would provide a source of multipotential stem cells that are not rejected. These could also Human cloning as a source of cells or be vectors for gene therapy. A gene could be tissue inserted into a somatic cell from the patient, Cloning is the production of an identical or near- followed by selection, nuclear transfer and the identical genetic copy."6 Cloning can occur by fis- culture of the appropriate clonal population of sion or fusion. Fission is the division of a cell mass cells in vitro. These cells could then be returned to into two equal and identical parts, and the devel- the patient as a source of new tissue (for example opment of each into a separate but genetically bone marrow in the case ofleukaemia) or as tissue identical or near-identical individual. This occurs without genetic abnormality (in the case of inher- in nature as identical twins. ited genetic disease). The major experimental Cloning by fusion involves taking the nucleus issues which would need to be addressed are from one cell and transferring it to an egg which developing clonal stability during cell amplifica- has had its nucleus removed. Placing the nucleus tion and ensuring differentiation into the cell type in the egg reprogrammes the DNA in the nucleus needed.'3 It should be noted that this procedure to replicate the whole individual from which the does not necessarily involve the production of a nucleus was derived: nuclear transfer. It differs multicellular embryo, nor its implantation in vivo from fission in that the offspring has only one or artificially. (Indeed, cross-species cloning- genetic parent, whose genome is nearly identical fusing human cells with cow eggs-produces to that of the offspring. In fission, the offspring, embryos which will not develop into fetuses, let like the offspring of normal sexual reproduction, alone viable offspring.17) inherits half of its genetic material from each of A related procedure would produce totipotent two parents. Henceforth, by "cloning", I mean stem cells which could differentiate into multipo- cloning by fusion. tent cells of a particular line or function, or even Human cloning could be used in several ways to into a specific tissue. This is much closer to repro-copyright. produce cells, tissues or organs for the treatment ductive cloning. Embryonic stem cells from mice of human disease. have been directed to differentiate into vascular endothelium, myocardial and skeletal tissue, hae- mopoietic precursors and neurons.'8 However, it HUMAN CLONING AS A SOURCE OF MULTIPOTENT is not known whether the differentiation ofhuman STEM CELLS In this paper I will differentiate between totipotent totipotent stem cells can be controlled in vitro.http://jme.bmj.com/ and multipotent stem cells. Stem cells are cells Unlike the previous application, the production of which are early in developmental lineage and have organs could involve reproductive cloning (the the ability to differentiate into several different production of a totipotent cell which forms a blas- mature cell types. Totipotent stem cells are very tomere), but then differentiates into a tissue after immature stem cells with the potential to develop some days. Initially, however, all early embryonic into any ofthe mature cell types in the adult (liver, cells are identical. Producing totipotent stem cells lung, skin, blood, etc). Multipotential stem cells in this way is equivalent to the creation of an early on September 26, 2021 by guest. Protected are more mature stem cells with the potential to embryo. develop into different mature forms of a particular for bone marrow stem cells PRODUCTION OF EMBRYO/FETUS/CHILD/ADULT AS A cell lineage, example, SOURCE OF TISSUE can form either white or red blood cells, but they An embryo, fetus, child or adult could be cannot form liver cells. produced by cloning, and solid organs or Multipotential stem cells can be used as differentiated tissue could be extracted from it. a. a vector for gene therapy. b. cells for transplantation, especially in bone Cloning as source of organs, tissue and marrow. cells for transplantation THE NEED FOR MORE ORGANS AND TISSUES Attempts have been made to use embryonic stem Jeffrey Platts reports: "So great is the demand that cells from other animals as vectors for gene as few as 5% of the organs needed in the United therapy and as universal transplantation cells in States ever become available".'9 According to humans. Problems include limited differentiation David K C Cooper, this is getting worse: "The and rejection. Somatic cells are differentiated cells discrepancy between the number of potential of the body, and not sex cells which give rise to recipients and donor organs is increasing by sperm and eggs. Cloning of somatic cells from a approximately 10-15% annually"."2 Increasing Savulescu 89 J Med Ethics: first published as 10.1136/jme.25.2.87 on 1 April 1999. Downloaded from procurement of cadaveric organs may not be the in remission in leukaemia before use for reconsti- solution. Anthony Dorling and colleagues write: tution during relapse. "A study from Seattle, USA, in 1992 identified an Lucas II In this version of the example, the drug annual maximum ofonly 7,000 brain dead donors causes Lucas's healthy skin cells to turn into in the USA. Assuming 100% consent and healthy bone marrow stem cells. There is no suitability, these 14,000 potential kidney grafts relevant moral difference between Lucas I and II. would still not match the numbers of new patients We should develop such drugs and doctors would commencing dialysis each year. The clear implica- be negligent if they did not use them.