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Human proteins in sheep's milk?
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Animal organs for human?
Mice as models of human disease?
Animal genetic engineering is one of today's key issues. Scientists are increasingly able to make genetic changes in animals, and great benefits are being claimed, but many are asking whether we should be doing it, and how society should control such developments. In 1998 the Church of Scotland SRT Project produced a new book "Engineering Genesis", a unique 5 year expert working group study of the ethical and social issues in non-human genetic engineering, involving prominent specialists in genetics, ethics, theology, sociology and animal welfare. This information sheet gives a few of our findings on animal issues.
What's New?
But it's not always straightforward. For example, although this should be more specific than conventional breeding, most attempts to genetically engineer farm animals to enhance production have not been promising, except perhaps in fish. Most applications so far are to find novel uses for the animal. And this raises the question of what are, and are not, acceptable changes for humans to make in animals.
Are We Playing God? Some equate the creation of transgenic species with Old Testament prohibitions of mixing kinds. But is changing one or two genes a wholesale violation? A sheep with one human gene is still primarily a sheep. Is the true nature of something in its detail or its whole essence? If it is in the detail, transgenesis will be unacceptable, as a change to a blueprint. If it is in the essence of the whole creature - a more biblical understanding - then the limited scale of most genetic alterations would not amount to crossing a line, but creating a chimera (a 50-50 genetic hybrid), or cloning by fusing one animal nucleus in the egg of another, might do.
1. Human Proteins in Sheep's Milk
2. Animal Organs for Human Transplants - Xenotransplantation
Is there a valid perception here, that xenotransplantation is unnatural, in a way that eating a pig is not? Animals eat animals, but they do not swap organs. You cannot justify using animals for organs purely on the basis that we eat them. There must also be a substantial human benefit. As in many developments in biotechnology, we need to be wary of exaggerated claims and raising unrealistic hopes. Without putting it to the test, there is no assurance that animal organs would yield prolonged extensions of good quality life. We felt there was a case for trying, but with a proviso about animal welfare. Pigs are sociable and highly inquisitive. To rear pigs to be disease free might mean a very artifical living environment. There limits to how far we may use animals to replace human body parts. Beyond a certain point, either of animal suffering or poor efficacy, it would not be justified. There's an ultimate limit. We can't make ourselves immortal by changing worn out organs!
3. Animals as Models of Human Disease
4. Cloning Animals
For centuries, humans have been doing a type of genetic engineering - selectively breeding animals and plants to enhance particular genetic traits, based on outward appearance, like leaner meat or an higher growth rate. Now it's possible to manipulate specific genes in the laboratory, adding, deleting or altering genes to produce some desired effect. For the first time we can mix genes across very different species.
Some say that to tamper with genes at all in this way is usurping our human position - playing God. How can we finite creatures know enough to make far-reaching changes to the stuff of life without violating what God has created? Are we not also fallen creatures, whose broken relationship with God means we have lost the moral sense of what is appropriate to do in nature? Instead we get carried away with pride at our technological achievements, and do not match them with good judgement about their use. Now this may be true, but why then draw the line at genetics, rather than any other intervention in nature? The inherent power in genetic changes means we should act with caution and humility, rather than impose an absolute prohibition.
Can there be a right sense of "playing God" - that we are to reflect God's image to the rest of creation in the way we develop and re-order it, if it is rightly done? If genetic modification of non-human life could prevent famine, or provide therapies for disease, is that a right human endeavour? One strong case is the work pioneered at the Roslin Institute at Edinburgh, where the introduction of a human gene programmes a sheep to produce a human protein of potential medical use in her milk. The first product, for treating emphysema and cystic fibrosis symptoms, is undergoing clinic trials, and shows no signs of having harmed the sheep. Careful scrutiny is needed for this any other products which are set to follow, but the general principle seems ethically acceptable, unless we were to say that to modify any animal genetically is an unacceptable imposition on the dignity of a fellow creature.
See our Press Release on Producing Antibodies in GM Chicken Eggs
If it is an not abuse to make human proteins in animal milk, what about using an animal for spare parts to save human life? Pig hearts might overcome the shortfall in supply of human hearts, using genetic modification to trick the human body into thinking the heart was not from a foreign species. This "xenotransplantation" is highly controversial. It is currently on hold in the UK because of doubts, raised in the wake of BSE/CJD, whether pig diseases could transmit to humans. But should we do this to animals anyway? One common response is the ham sandwich argument. Since we breed pigs for food, what objection could there be? Isn't our "yuk" reaction just because we are unfamiliar with the idea, as we were with heart transplants a generation ago? Yet familiarity can also make people more concerned; take nuclear power for example. It's foolish to write off the yuk reaction as emotional. Scientific reasoning is not always a superior moral guide to our intuition.
Even more serious questions are posed by the commonest transgenic animals - genetically modified mice used as models for human genetic diseases or to test out possible therapies. The first example was the oncomouse, in which a human gene was added to cause the mouse to develop a mammary tumour. Because it is relatively easy to modify mice, a large number of mice now been genetically programmed to develop genetic diseases. Medical researchers say they could make very little progress on treating such diseases without these mice. Animal welfare groups say that to force a mouse to get cancer in this way is a cruelly unacceptable use, whether or not it experiences serious distress or pain. There are two separate cultures, each driven by an overriding ethical criterion. There appears no simple answer. But the availability of model mice is now so widespread that there is a danger that researchers stop asking if they really need to use them every time. Have such mice become mere catalogue items and no longer God's creatures?
Sometimes mouse models are not very effective. The symptoms of cystic fibrosis in a mouse are quite different from humans. It has been suggested a better way to reproduce and model the disease is to put the defective human CF gene into a sheep. If dilemmas are posed for mice, going to a larger animal begins to push the ethical envelope to the limits. The recent announcement of a GM monkey surely goes one step too far. Primates have high levels of sentience are so similar in , then how much more for larger animals. See our Press Release on GM Monkeys
The Roslin Institute's now famous sheep cloning work is actually aimed primarily at better ways of doing genetic modification in animals than the very hit and miss methods used so far, and it shows promise of achieving its aim. In a separate information sheet we ask Is it Right to Clone Animals?
From 1993 to 1998 we ran a multi-disciplinary expert working group study, leading to the book Engineering Genesis, acclaimed as one of the most balanced studies available on these issues.
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Ref.No. GENANINF Expanded update 12/1/01.
