Is cloning from adult mammals a desirable development?
Echo Issue Outline: copyright © Echo Education Services
First published in The Echo news digest and newspaper sources index.
Issue outline by J M McInerney
What they said ...
`It basically means that there are no limits. It means all of science fiction is true. They said it could never be done and now here it is, done before the year 2000'
Dr Lee Silver, professor of biology, Princeton University
`It's a sort of party trick as far as the science goes. It was not done to solve a pressing agricultural or medical problem. They did it because they could'
Dr David Vaux, molecular biologist, Walter and Eliza Hall Institute, Melbourne
On February 23, 1997, it was announced that a British genetic research team had succeeded in cloning a sheep from a cell provided by another adult sheep.
The announcement created immediate controversy. Some groups hailed the development as a revolutionary breakthrough which would transform animal husbandry. There was also enthusiasm about pharmaceutical benefits and readily available transplant organs.
Others were concerned at the dangers the development might pose both to other species and to human beings. There was anxiety expressed at the possibility of human cloning.
The debate is still far from resolved.
A brief note on cloning
As it occurs in nature, cloning is reproduction involving only one parent. It is also referred to as asexual reproduction.
Cloning occurs when a single cell from the parent organism begins to divide and develop in such a way that a new organism is produced. This new organism has exactly the same genetic make-up as its parent and is usually physically identical to its parent.
In sexual reproduction, two parents are involved. Each contributes a sex cell or gamete. When these gametes join or fuse a new organism begins to develop.
A sexually produced organism will have a genetic make-up which is a combination of that of both of its parents. Physically it will usually display a variety of features, some inherited from each parent.
Background
The cloned sheep, named "Dolly", was the work of a research team at the Roslin Institute in Edinburgh. She was born in July, 1996. The project was funded by both the British Ministry for Agriculture and some private firms. Pharmaceuticals Proteins Ltd is one sponsor. The company hopes to develop commercial applications for the cloning technique.
The procedure which produced Dolly involved taking a gamete (an egg or ova) from one ewe and removing its nucleus or centre, which contains its genetic material. This was then replaced with genetic material taken from a mammary gland cell of another sheep. The modified gamete was then implanted in the uterus of a third sheep.
Because there was no fusion of genetic material from different parents, this was asexual reproduction and Dolly is an exact physical replica of the sheep which contributed the genetic material from its mammary gland cell.
A number of features of this procedure make it unusual. Cloning of animals has occurred before, however, it has apparently involved removing the genetic material from one gamete and replacing it with genetic material from an embryo. It had previously been believed held that it was not possible to clone using genetic material drawn from an adult cell.
Being able to use adult cells in this way, means that those interested in breeding animals displaying a certain physical characteristic, can check that the characteristic is shown by an adult animal and then clone other animals from that one parent. All of these cloned animals should display that characteristic.
When cloning from embryo cells, a breeder does not know exactly what characteristics the embryo will display as an adult.
Less than two weeks after scientists at the Roslin Institute in Edinburgh announced they had cloned a sheep from an adult sheep cell, an American research team announced they had cloned monkeys.
This was seen as significant because monkeys are primates and so much more closely related to human beings. The work with monkeys, however, involved cloning monkeys from embryo cells, not from adult cells.
Shortly after the monkey report, it was announced that a male child had been cloned `accidentally' as part of an IVF procedure. This report was later denied and even in its original form appears to be referring to the birth of twins through the fusion of two gametes and not to a cloning process.
Arguments in favour of cloning from adult mammals
Those who argue in favour of cloning from adult mammal cells usually begin with the advantages this could offer animal husbandry.
According to this line of argument, carefully bred (or genetically engineered) animals, with desirable characteristics would be able to pass on those exact characteristics to their cloned progeny.
It has also been suggested that cloning could be a means of gaining offspring from valuable neutered animals, for example gelded horses.
Another claim made for the procedure is that, with further development, it may allow for the reproduction of currently extinct animals.
According to this line of argument, it may one day be possible to remove the genetic material from the gamete of an animal related to the extinct creature and replace it with genetic material from preserved remains of the extinct animal, thus producing a clone of that animal. (Currently it is not possible to clone from cells which are no longer alive, though, the cloning procedure does make use of special freezing techniques which puts the cell into a sort of stasis.)
Those who argue in favour of cloning from adult mammals tend to hold one of three positions on the possibility that this technology might result in attempts to clone human beings.
On the one hand there are those who hold that such fears are groundless because the procedure for cloning humans will not be developed or used.
Those who hold this view tend to stress either that current legislation prohibits the cloning of human beings or that public opinion would never allow such a procedure.
This is essentially the view that has been put by Dr Michael Wooldridge, the federal Health Minister.
Dr Wooldridge has pointed out that cloning is governed in Australia by state rather than federal law. Dr Wooldridge has noted that Victoria, Western Australia and South Australia have already banned the practice. Dr Wooldridge has also noted that `in the other states and territories, what is not covered by the National Health and Medical Research Council or the Australian Research Council would almost certainly be found to be unethical through either hospital or other research institute guidelines.'
Similarly, Graeme O'Neill, commenting in The Herald Sun, has argued that the ethics of the general research community and the force of popular opinion would prevent any genetic research scientist attempting to clone a human being.
`What sane biologist, knowing the community's hyper-sensitivity to such an issue, and the media sensation it would inevitably arouse, would even attempt such a thing?' Graeme O'Neill asks.
Mr Arthur Caplan, a bio-ethicist at the University of Pennsylvania, has made a similar observation.
Mr Caplan suggested that public outcry at the prospect of human cloning meant that `you're probably heading down the path to criminal arrest, not the Nobel Prize, if you try this in people.'
Then there are those who argue that human cloning is unlikely to occur because it would result in no obvious advantage.
Dr Karen Dawson, a geneticist at Monash University's Institute of Reproduction and Development, has claimed, `Scientists have been able to clone a human being for 15 years, but who would really want to?'
It has been suggested, for example, that any individual's genetic make-up is only partially responsible for how he or she ultimately develops. The rest is the result of the interaction of genetic make-up with environmental factors.
Thus, it has been claimed, attempts to create a second human being who is an exact replica of another, either alive or dead, are doomed to failure.
Columnist Terry Lane, writing for The Age, referred to the fictional scenario presented in the film, `The Boys from Brazil', in which an abortive attempt was made to reproduce a number of Adolf Hilters via cloning.
`There is no guarantee that a batch of little Hilters will all run true to form,' Lane writes. `Some might be raised by nice foster parents and turn out to be as decent as their adopted mum and dads.'
Dr Ian Wilmut, the head of the research team which developed Dolly, has similarly stated, `The idea that you can bring back a child, that you can bring back your father - it is simply nonsensical. You can make an identical copy, but you can't get back the person you have lost.'
There are also those who argue that the prospect of cloning using human cells offers more benefits than it does grounds for concern.
It has been suggested, for example, that an infertile couple using an IVF program might well prefer to have the embryo for implantation produced by cloning.
Depending on the circumstances of the individual couple, cloning could mean that the embryo would be the product of the genes of one partner, rather than the product of one partner's and a donor's genes.
It has also been suggested that a couple whose baby had died might justifiably wish to use cloning to attempt to replace that child.
Moving away from the direct cloning of human beings, it has been suggested that cloning using human cells could have enormous benefits in the treatment of human diseases.
For example, it has been suggested that the human protein, interferon, used in the treatment of cancer and HIV/AIDS, could be genetically engineered so that it was produced in an animal's cells. That animal could then be cloned so that large numbers of interferon-producing animals were created.
Similarly, it has been suggested, genetic engineering could be used to produce animals with organs that were not rejected if transplanted into a human being.
Science reporter, Youssef Ibrahim, has speculated, `Pig clones could be genetically engineered to be a source of organs for humans. Scientists would grow pig cells in a laboratory and add genes that would make their surface proteins identical to proteins that coat human cells.
The researchers would then make cloned pigs from these genetically engineered cells.
The cloned animals would have organs that look, to a human immune system, like human organs and so they would not be rejected.'
It has also been suggested that genetic engineering could produce cows whose milk contained the same protein as human breast milk. Cloning could then produce such cows in large numbers and the result would be a better alternative source of milk for infants.
Arguments against cloning from adult mammals
Arguments against cloning from adult mammals are of two types. There are the general arguments offered against the cloning of any animal species, then there are the particular arguments offered against the cloning of human beings.
The major practical argument offered against the cloning of any animal species is that it will reduce the variations which naturally occur within that species.
Sexual reproduction, because it produces offspring who carry a mixture of the genetic coding of each parent, produces far greater variety or diversity than does asexual reproduction.
Diversity is often seen as a good thing because having a variety of characteristics in a particular group can protect it against diseases and other environmental threats.
It is claimed that variety among offspring tends to mean that at least some will be immune to a particular disease and thus the species will survive. It is further claimed that if all offspring are identical and none is immune to a particular disease all will die.
This position has been argued by Mr Gyorgy Scrinis of the history and philosophy of science department at Melbourne University.
Mr Scrinis has written, `One consequence of this erosion of genetic diversity is that animals become more vulnerable to changing environmental conditions. Any disease that enters a genetically identical herd can more easily spread through and wipe out the entire herd. When this uniformity encompasses large regions or the entire planet, then the potential dangers are exacerbated.'
It has also been claimed that genetic diversity provides a rich gene pool from which selective breeders can draw when they wish to develop animals that display particular characteristics.
According to this line of argument, if cloning were to become widespread in agriculture the range of species would be further reduced and so would geneticists' opportunities of breeding from naturally-occurring strains with desired features.
Cherry Ripe, writing in The Australian, has claimed, `According to the FAO (United Nations' Food and Agriculture Organisation) 30 per cent of the world's breeds of livestock are at high risk of extinction.
Surely cloning can only lead to further homogenisation and therefore a greater reduction in domestic animal biodiversity?'
There are also those who are concerned that, by cloning animals, human beings are displaying a lack of respect for animal life.
It has been suggested that interfering with the genetic make-up of another species is not a legitimate activity and indicates a distorted set of values.
This position has been put by Mr Gyorgy Scrinis. Mr Scrinis claims that we are turning all other living things into commodities that exist only so we may exploit them.
`Like "Dolly", the cloned sheep, all engineered animals will be patented and owned by the individuals and corporations that create them, thereby further extending the commodification of nature ... the use [of cloning] and other such techniques on animals already affects us in the sense that it transforms our relationship to these animals, and therefore says something about the kind of people we are to manipulate and utilise animals in this way, ' Mr Scrinis argues.
On the question of the possible cloning of human beings there have been a number of objections offered. Some of these objections are similar to those offered in opposition to the cloning of other species. Others stress the special value which, proponents of this position claim, should be attached to human life.
The main argument offered against the cloning of another human being is that is shows a lack of respect for life. According to this argument to attempt to replicate one human being in another shows a lack of respect for the second person and a lack of regard for his or her human uniqueness.
It has further been suggested that cloning could ultimately lead to the practice of eugenics, that is, attempts to breed a race or a group of people displaying what were judged to be superior characteristics.
It has been argued that eugenics would be damaging both for the individuals produced in this manner and for society as a whole.
For example, it has been suggested that children who were breed to be intelligent or to be skilled athletes may not be valued in themselves, but would only be appreciated by their parents to the extent to which they displayed the qualities which had been supposedly bred into them.
This position has been put by John Fleming, director of the Southern Cross Bioethics Institute, Adelaide.
Mr Fleming has argued, `What of the cloned child and his or her rights to be conceived and born of the conjugal love of his parents? Will such children believe that they are loved unconditionally or only in so far as they live up to the expectations of those who wanted "gifted" children?'
It has also been suggested that a society which allowed cloning or selective breeding of human beings would become intolerant of diversity and may either victimise or attempt to eradicate those with physical deformities, different racial characteristics or different sexual preferences.
Cloning has also been condemned by the head of the Catholic Church, Pope John-Paul II. In what has been regarded as a reference to cloning, Pope John-Paul II has criticised those whom he says `trample on human dignity for the sake of money and power ...'
Finally, it has been suggested that the use of cloning to create animal organs to be transplanted into people could lead to a practice where human foetuses were cloned in order to supply transplant tissues.
Mr John Fleming has cited with disapproval the view of bioethicist Peter Singer that it would be acceptable to clone a foetus to supply transplant tissue so long as the tissue was harvested before the foetus had developed consciousness or the foetus had been genetically modified so that a brain would not form.
Mr Fleming condemns this proposal because he implies it shows a lack of respect or regard for the life of the foetus who supplies the "spare parts".
Further implications
Cloning from adult mammal cells is such a potentially momentous development that it is not possible to suggest with any certainty what either its immediate or long-term consequences are likely to be.
Perhaps most remarkable of the claims made to date is that of Dr Ian Wilmut who has suggested that if research were to continue in that direction, it should be possible to clone a human being in about two years.
However, whether such a development will actually occur within such a short time is highly problematic.
It has been announced that Britain is going to cut off funding for the project that produced "Dolly", the first cloned sheep.
One Edinburgh scientist suggested that the Ministry of Agriculture had been made so uncomfortable about suggestions of human cloning that it decided to axe much of the biotechnology research it sponsors at Roslin.
One thing which does seem fairly probable is that the law-making bodies of the world are likely to adopt a more conservative attitude toward cloning procedures than the scientific community.
There are already a number of attempts being made to regulate cloning technologies in an attempt to ensure they do not develop in directions that society considers dangerous or inappropriate.
In Britain, less than a week after the Edinburgh group announced they had cloned a sheep from an adult cell, a government advisory body on genetic engineering was asked to examine legal safeguards on cloning.
The chairperson of the group, titled the Human Genetic Advisory Commission, is Mr Colin Campbell. Mr Campbell has stated, `Scientists invent techniques. We will try to control and guide scientists rather than let them impose solutions on us.'
In the United States, President Bill Clinton has asked an expert bioethics panel to review the legal and ethical ramifications of cloning with special regard to any implications for humans.
However, whatever legal restrictions may be placed on the development and use of cloning procedures, these procedures seem certain to continue.
It seems highly unlikely that any ethics body would prohibit a procedure that promises the plentiful and apparently safe production of pharmaceuticals that can assist in the treatment of diseases such as AIDS and cancer. It also seems unlikely that any group would recommend against a technology that may make animal organs suitable for human transplants or that may increase the yields of crops and the productivity of farm animals.
Finally, human cloning seems certain either to remain illegal (in those countries that already have laws that can be applied to this question) or to be made illegal. Only time will tell whether legal restrictions will effectively prevent researchers cloning human beings.
Sources
The Age
24/2/97 page 7 news item, `Fantasy of animal cloning now reality'
25/2/97 page 13 analysis by Gina Kolata, `Hello Dolly'
25/2/97 page 13 news report by Youssef Ibrahim, `A scientist who savors obscurity'
25/2/97 page 14 editorial, `The gene is out of the bottle'
25/2/97 page 7 news item by Steve Dow, `Ethicists predict cloning of humans'
25/2/97 page 7 news item by Peter Spinks, `Discovery changes the rules of biology'
27/2/97 page 15 comment by Paul Komesaroff, `The facts and fiction of cloning'
27/2/97 page 15 comment by Loane Skene, `Weighing up the rules against more of the same'
2/3/97 page 10 news item, `Cloning funds get the chop'
2/3/97 page 14 comment by Terry Lane, `The hard copy'
3/3/97 page 11 news item by Rick Weiss & John Schwartz, `US cloning experts attend to some serious monkey business'
5/3/97 page 14 news item, `Cloning haunts Germany's Nazi past'
6/3/97 page 4 news item by Karen Middleton, `Human cloning not on here, says minister'
16/3/97 page 20 editorial, `Sorting the sheep from the ethics'
The Australian
25/2/97 page 3 news item by Graeme Leech, `Scientists deny wolf in sheep's cloning'
1/3/97 page 22 comment by Graeme Leech, `The genetic genie'
4/3/97 page 6 news item, `Vanity drives desire for cloning, says geneticist'
7/3/97 page 12 comment by Cherry Ripe, `Keep clones a breed apart'
8/3/97 page 15 news item by Nigel Hawkes & Tom Rhodes, `Human clones within two years'
10/3/97 page 3 news item, `Cloned boy an "accident"'
The Herald Sun
25/2/97 page 5 news item by Helen Carter & Liz Deegan, `Clone ethics warning'
25/2/97 page 18 editorial, `Don't send in the clones'
1/3/97 page 23 comment by Helen Carter, `They're off and cloning around Jurassic Park'
1/3/97 page 25 news item, `Close look at cloning laws'
2/3/97 page 82 comment by Graeme O'Neill, `The morals of manipulation'
3/3/97 page 3 news item by Helen Carter, `Monkeys cloned'
6/3/97 page 19 comment by John Fleming, `Forget Hilters, this is serious'
8/3/97 page 22 comment by Paul Gray, `We are not sheep'
11/3/97 page 13 news item by Kim Wilson, `Human clone denial'