Lists of Pros and Cons of Genetic Engineering
David Heaf
27th April 2001
Introduction
Over the past few years many students have asked Ifgene for help with defining the pros and cons of GE. But if an issue is simply divided into black and white pros and cons the social process has more the quality of a debate -- i.e. polarisation of opinions -- than a dialogue. With a dialogue there is some preparedness on either side to listen to others' opinions, modify their own and reach some common ground as a basis for action. Dialogue is the approach preferred by Ifgene. However, in view of the sheer number of requests for lists of pros and cons we are offering this document. It presents some of the common arguments from both sides and an effort has been made to strike a balance. But the lists below are not exhaustive. Much more can be said both for and against. Furthermore, some of the statements will seem like downright lies depending on what opinions or world view you, the reader, already have. We have omitted a section on micro-organisms at for the time being -- many of the concerns are raised in the other sections. Also, at the present time, many of the statements by people on both sides of the debate amount to crystal ball gazing. Genetic engineering is still a relatively young technology -- about 25 years old -- and many of the predictions about it, for better or worse, have yet to be verified in practice.
It should be borne in mind that what follows is only one man's perspective on the 'gene scene'. Feedback from readers of whatever persuasion offering further points for consideration for inclusion in these lists would be especially welcome.
Here the term 'genetic engineering' (GE) shall mean 'transgenesis' or 'recombinant DNA technology', -- i.e. the technology of copying pieces of genetic code from one organism of the same or different species to another by means of the techniques of the molecular biology laboratory. It results in a 'genetically modified organism' (GMO). Genetic engineering is sometimes described as 'modern biotechnology', 'gene technology', 'genetic modification' (GM), 'genetic manipulation' or 'genetic mutilation'. In what follows, some mention is also made of cloning.
Readers may need to make use of the glossary of terms (meaning of words used).
Contents
#Genetic engineering in general
#Genetic engineering of plants (crops)
#Genetic engineering of animals
#Application of genetic engineering to human beings and their health
Genetic engineering in general
Pros |
Cons |
With the discovery of DNA and unravelling the genetic code it contains, molecular biologists have finally come close to understanding what determines the form and function of organisms and can use this to design organisms at will. This is illustrated by the experiments on the transgenic fruit fly which has eyes on its antennae (Walter Gehring, Basel Biocentre, Switzerland. see the year 1994 in history.htm ). This new technology will have more benefits for human existence than all the past technologies put together. | Scientists are no closer to understanding what
determines the form and function of a living organism than they were a century ago before
the term gene was coined. As Craig Venter, a leader in the Human Genome Project put it:
"We know shit about biology". Scientists have tended to concentrate on physical
causality -- genes determine form and function -- but they are looking in the wrong place.
Genes and their proper expression as structural, regulatory or enzymic proteins are merely
one of the necessary conditions for the idea underlying an organism to manifest. The
essence of the organism is its entelechy or telos. Other necessary
conditions for an organism to manifest include nutrient, water, warmth, light and many
other factors to do with the earth as a planet in a cosmos. The optimistic predictions of the molecular biologists and genetic engineers is reminiscent of those offered by the early proponents of nuclear power. In the 1950s electricity was forecast to become too cheap to make it worth metering, but the reality is that society is left with a legacy of nuclear waste the cost of dealing with which will place an immeasurable burden on future generations. |
Ever since agriculture and the domestication of animals
and plants began man has been modifying their genetic make-up by selective breeding (e.g.
broccoli, Brussels sprouts and cabbage came from a single
species of mustard).
|
Traditional breeding involves gene exchange in the proper context within which they function with all the checks and balances of the biological processes of the organism itself and of the organism's normal interaction with its environment. GE is out of context. GMOs often behave very differently when taken from the laboratory, greenhouse or field trial situation into the real-life context where they will be used, e.g. a gene for red flowers was inserted into a white petunia. The petunia turned red but also produced more leaves and shoots, had lower fertility and was more resistant to fungi. None of these additional effects was predicted. Over 90% of transgenic plants are discarded during the development process, most even before the plants leave the laboratory. The reason for so many rejects is because they do not express the desired gene or they are made unhealthy by the genetic engineering. |
Ever since man began to ferment fruit and milk products thousands of years ago, he has been using biotechnology. | Traditional biotechnology uses natural organisms in contexts to which they are adapted whereas GE creates completely new genetic make-ups that could never have come about by natural processes. |
All attempts to define what species barriers are have so
far had various shortcomings. The genomes of many organisms can be shown to contain gene
sequences from totally unrelated organisms which might commonly be assumed to be on the
other side of a 'species barrier' (e.g. the mariner sequence in the fruit fly Drosophila,
is also in humans). Mules (horse x donkey) have long since existed, but nobody is complaining. And the technique of grafting different plants/trees onto each other is ancient. |
GE crosses species barriers. Crosses are made which would never occur in nature. |
All technology is unnatural (unless we hold that man and all his creations are part of the totality of nature). (see Shakespeare, A Winter's Tale, IV:III:82-103) | GE is unnatural. |
We have consciously interfered with evolution through breeding, habitat management and even selection of our own spouses for millennia without any noticeable dire consequences. | Scrambling genomes will lead to total chaos in evolution. |
"And God said, Let us make man in our image, after
our likeness: and let them have dominion over the fish of the sea, and over the fowl of
the air, and over the cattle, and over all the earth, and over every creeping thing that
creepeth upon the earth." (Genesis 1:26) "Human beings are themselves part of nature, creatures within creation. Human discovery and invention can be thought of as resulting from the exercise of God-given powers of mind and reason." (Church of England Board) |
Biotechnologists are playing God. |
GE is a very precise way of introducing desirable traits into economically useful organisms. The techniques are improving all the time and it is increasingly possible to insert genes at a precise locus in the host organism's genome. This is called 'gene targeting'. | GE disrupts the integrity of the recipient genome with unpredictable side effects including 'gene silencing' both of the inserted gene and other unrelated genes in the organism. GE cannot readily control the number of copies of the gene that are inserted into the host, nor where in the genome they will end up. Inserted genes can disrupt the function of existing genes in ways which may not show up until later generations. |
GE often, but not always, needs to use bacteria, viruses or plasmids as vectors to shuttle the genes of interest into the target organisms. These vectors are crippled by having the parts of their genomes removed that would make them infective. As the technology improves it becomes less necessary to use infective agents as vectors. | GE makes use of pathogenic organisms such as viruses and bacteria as vectors of the gene that is being transferred. In other words, the target organism has to be made ill just to get the gene in, sometimes with tragic consequences. The pathogens can kill the target organism or could spread into the environment with unpredictable and dangerous consequences. Even crippled vectors can recombine DNA and therefore genes with their normal counterparts in their surroundings and thus suddenly and unpredictably become infective. |
Molecular biologists acknowledge that they are only modifying one aspect of an organism's totality. However, they examine the organisms produced in great detail, sometimes taking them through breeding programmes for years to be sure that they are behaving in the way that other normal members of the same species behave which have not had the genetic modification. | GE is dominated by the reductionist thinking of genetic determinism which believes that the genetic make-up is what makes the organism what it is. An organism is as much an expression of its environment as it is of its genes. Concentrating on the genes, therefore, is one-sided. Furthermore the organisation within a cell and its interaction with other cells is also inherited along with the genes. An organism is as dependent for its survival as much on these epigenetic factors as on its genome. |
The fact that horizontal gene transfer occurs all the time in nature, (e.g. the constant exchange of genetic information between bacteria, viruses etc, or the rarer 'jumps' of genes such as may have contributed to the ubiquity of the mariner sequence listed above) and has caused no problems, can be taken as evidence that it poses no serious danger. | GE exposes people to the increased dangers of horizontal gene transfer, a process whereby genes are passed not 'vertically' down the generations in the usual way but 'horizontally' from organism to organism and from species to species. |
Enzymes can be produced from GM microorganisms for use in industrial processes including food manufacture. | Industrial enzymes used in anything from washing powders to food processing are already a major source of allergies. |
GE does involve some risk taking but all procedures are subject to strict risk analysis and monitoring. The risk is therefore minimal. No popular technology is without risk, e.g. the motor car which kills tens of thousands each year. | GE is potentially dangerous and therefore involves taking risks. The consequences could be devastating and irreversible. Furthermore, the adverse consequences could take years to show and the company liable for any damages may have long since ceased trading. |
Genetic engineering of plants (crops)
People are increasingly becoming aware of the fact that a plant has intrinsic worth or value (integrity, dignity) and therefore has an ethical status. However, when considering plant biotechnology, so far as the plant itself is concerned, strong moral reservations are as yet relatively rare. After all, so far as we know, a plant cannot feel, is not sentient. But plant biotechnology, insofar as it impinges on other human beings, raises serious moral issues. These concern the rights claimed by these other human beings, e.g. the right to eat food that does not contain transgenes or the growing of which does not destroy the environment which we all have to share.
Pros |
Cons |
Less tillage needed, especially with crops containing herbicide tolerance transgenes, therefore conserves fertility through minimising soil damage through compression. | GE agriculture claims low tillage weed control: this can be achieved by ending the practice of monoculture and instead introducing proper crop rotations designed specifically to combat the weeds of the particular locality. Monoculture creates a weed paradise. |
All countries face problems caused by alien species
accidentally or deliberately introduced into a new environment (e.g. prickly pear in
Australia). The main factor permitting this is international travel, but nobody has
suggested that this should be banned. The problem of alien species is manageable, as would
be the problem of genetic pollution caused by spread of seeds or pollen. As regards pollen contamination from GM varieties and the call for compensation for growers of non-GM or organic varieties whose crops are contaminated, if one is to be fair one might reasonably expect growers of non-GM and organic varieties to compensate growers of GM crops if they are contaminated with non-GM or organic pollen. |
Genetic pollution from transgenes spreads into other organisms through pollen, seeds and microbial processes. It is fundamentally different from other forms of pollution because once the genes are out, they cannot be recalled. The best example of pollen contamination is provided by the Seeds oilseed rape (canola) seed which was multiplied in Canada. It was officially confirmed in May 2000 that this seed was contaminated with unapproved GM rapeseed and accidentally shipped to UK and other countries. By then it had been planted in Europe and large acreages of the young crop had to be destroyed. According to Advanta, the contamination occurred as a result of cross-pollination in Canada, where the seed was produced. The nearest source of GM contamination was 4 kilometers away. |
Organic farming has long accepted accidental contamination from herbicide sprays from neighbouring farms. If there is concern about GMOs, DNA tests can be carried out. | Risks destroying organic farming which rules out the use of GM organisms. Who will compensate organic farmers for the extra surveillance and analysis which will be needed to ensure that the organic food chains remain free of GMOs? |
The Starlink debacle is indeed a lesson that the GM food producers will learn from. Identity Preservation Systems are being put in place, verified by DNA analysis, to ensure that GM and non-GM supplies are kept separate. | The massive contamination in 2000 of the USA corn
(maize) crop and human food chain by Starlink, a variety which is not approved for human
consumption, shows that genetic pollution from transgenic crops to non-transgenic crops
and food is inevitable. Starlink maize produces the Cry9C protein which may be a human
allergen. Two other major contaminations of ordinary seed (maize and oilseed rape (canola)) with GM seed have already occurred leading to emergency recalls of the product. |
Reduces labour costs. | Sustainable organic agriculture creates much needed jobs in depressed rural economies. |
Environmentally relatively benign herbicides are used
and less of them. Opposing GM crops forces farmers to use herbicide resistant varieties which have not been made by GM such as those resistant to sulphonylurea herbicides which more readily give rise to herbicide resistant weeds. |
Promotes "agribusiness", therefore more herbicide use. Herbicides are responsible for much illness in farm workers and contaminate drinking water. |
Enhances biodiversity by allowing weeds to continue growing for longer thus providing nutrition for animals. After weed kill a mulch forms which hosts a thriving population of insects, arthropods etc. | The total herbicides used with herbicide tolerant crops kill all weeds thus reducing biodiversity in the field. |
No insecticidal sprays needed on crops that have
insecticidal Bacillus thuringiensis (Bt)-toxin genes engineered into them. Plants with Bt or other insecticidal genes are likely to give rise to lower levels of mycotoxins in the final food product. Less insect damage means less opportunity for fungi to infect the plant and bring toxic substances. |
As with weed control, control of insect damage is achievable with properly designed crop rotation and other forms of good husbandry such as intercropping. Healthy plants not imbalanced by chemical fertilisers build up their own defences against insect attack. |
GM plants are carefully tested for environmental and
ecological impact, including their effects on earthworms and beneficial insects. Bt crops target only insects which attack the crop. Future insect resistance genes will be engineered to express in leaves and stem rather than in pollen and seed. There is already evidence that the Bt gene is expressed less in Bt corn pollen than in leaves/stems therefore the risk to butterflies (e.g. Monarch) through pollen drift onto their food plants (e.g. milkweed for Monarch) is diminished.
|
In relation to population variance, sample sizes in lab
and field tests (e.g. of earthworms) are sometimes too low to detect even large effects.
(see Michelle
Marvier, 2001) Insecticidal crops containing the gene for Bacillus thuringiensis (Bt)-toxin kill beneficial organisms such as bees, ladybirds, lacewings & butterflies (e.g. through pollen). The Bt plant remains falling to the ground are harmful to earthworms and other members of soil fauna. Bt toxins are secreted into soil from Bt plant roots and are toxic to lepidoptera in the soil (Stotzky, et al. Nature 402, 480 (1999)). The specific targeting and elimination of one insect pest has led to other pestiferous insect species moving into the ecological niche created by the disappearance of the first species. Getting rid of one problem simply created another. If Bt toxin transgenes spread to wild relatives of crop plants the wild plants may also develop resistance to insect herbivores. This could lead to the affected wild plants becoming invasive weeds. |
The problem of resistance to Bt toxin and other toxins engineered into crops can be countered by planting suitably sized 'refuges' of a non-GM variety of the crop at suitable intervals within the crop. The interbreeding of the wild population with the Bt-exposed potentially resistant population will dilute out the genetic trait and thus prevent it building up. | Putting the Bt toxin gene in the crop exposes the pest to the toxin for longer, thus allowing natural genetic resistance to the toxin to develop in the pest. So-called refuge systems do not work, partly because breeding cycles in the differing pest populations are not synchronised. Refuges of up to 40% of the acreage are having to be recommended and this is not practical or popular for farmers. The build up of Bt toxin resistance threatens to render ineffective an insecticide long used by organic agriculture. Increased use of biopesticides in transgenic crops deprives the ecosystem of one of its natural pest controls thereby putting at risk its ability to restore equilibrium after being upset by abnormal conditions. |
Helps solve the problem of world hunger by creating varieties which will make more efficient utilisation of scarce land and give higher yields because of better pest resistance, nutrient utilisation etc | World hunger will not be solved by technological means. It is a problem of inequitable distribution of wealth and corrupt governments. Reduces yields (e.g. cotton, soybeans and sugar beet in some areas). |
If herbicide resistance spreads to weed populations it
can be combated with another herbicide with a different active ingredient. The ecological and agricultural threat of a GM plant is no more than a non-GM invasive (exotic) species such as kudzu or purple loosestrife. Although improved crop yields can be engineered by genetically modifying plants, there is ecological concern over whether these plants are likely to persist in the wild in the event of dispersal from their cultivated habitat. The results of a long-term study of the performance of transgenic crops in natural habitats on four different crops (oilseed rape, potato, maize and sugar beet) which were grown in 12 different habitats and monitored over a period of 10 years show that in no case were the genetically modified plants found to be more invasive or more persistent than their conventional counterparts. (M. J. CRAWLEY, S. L. BROWN, R. S. HAILS, D. D. KOHN & M. REES. Biotechnology: Transgenic crops in natural habitats Nature 409, 682 - 683 (2001) © Macmillan Publishers Ltd) |
Enhances spread of herbicide resistance to wild weed
populations because the necessary genes are in the pollen which can then pollinate wild
relatives of the crop plant. This could create 'superweeds' especially if 'gene stacking'
of several different transgenes occurs. Spread of transgenes is also caused by birds,
animals & machinery carrying the seed to other locations (e.g. canola/rape on Ailsa
Craig isle, 10 miles from Scottish mainland) Increased weediness of GM crops is already beginning to show. In 1999 in Alberta, Canada canola (oilseed rape) volunteers (unwanted crop plants coming up the following year) resistant to three different herbicides have been discovered. A series of chemical and DNA tests confirm the weeds in farmer Tony Huether's field near Sexsmith are resistant to Roundup®, Liberty® and Pursuit® herbicide chemicals. Invasive species of plants can remain relatively unproblematic in a region for many years and then suddenly take a hold so much so that they become an economically significant nuisance. For this reason, the ecological impact of GM crops will be difficult to predict in the long term, i.e. over several decades. |
Most cultivars are unlikely to survive amongst wild plant populations and those with herbicide resistance that escape will have no advantage from the herbicide resistance trait unless that particular herbicide is used. Such volunteers can be controlled with other herbicides. | Transgenic herbicide resistant cultivars could escape into the wild and become problematic 'volunteers' in agriculture. These volunteers will require increased use of more toxic herbicides. |
Is a sustainable agriculture, because it reduces chemical inputs as well as fuel inputs for farm machinery. | Unsustainable -- based on greed not need. Helps chemical agriculture to proliferate. The only sustainable agriculture for the future is organic (including biodynamic & permaculture). |
Quicker and more precise than traditional breeding. | Breeding takes place outside the proper context, i.e. in the laboratory, therefore the crops are so weakened that they need to have the environment of the laboratory (soil sterilisation, artificial fertilisers and pesticides) brought to them in the field. Transgenic lines are unstable and can lead to crop failures (e.g. GM cotton in USA). |
A greater range of distinct disease-resistant varieties
can be created so that the farmer has a wide choice and can plant a mixture of several
varieties of the same crop in the same field to insure against disease attack. Disease resistance traits can be rapidly introduced to cultivars, e.g. rice, thus keeping ahead of the changing pattern of disease in a particular locality. |
Because of the huge investment in GM crops, the necessarily increased emphasis on single high-yielding varieties reduces genetic diversity within the crop itself. This can lay the crop open to massive losses when disease strikes. |
Novel drought and salt-tolerant cultivars can be created (important for Third World). | Novel varieties properly suited to a locality can be developed perfectly satisfactorily by sustainable organic plant breeding. |
Any royalties or technology fees are more than compensated for by advantages including higher yields and easier, therefore less expensive, husbandry. | No seed-saving by the farmer is permitted. The farmer
has to pay royalties to the biotech company. This undermines a traditional agricultural
prictice and particularly threatens peasant farming in developing countries. GM crops add to the tendency of modern chemical agriculture to undermine the autonomy of farmers and turn them into tractor drivers or machine minders for large transnational corporations. |
New varieties are tested for toxicity more than any crop
plants have ever been in the past, therefore they are likely to be safer. Jimmy
Clark, a professor of ruminant nutrition in Animal Sciences at the University of Illinois
at Urbana-Champaign, reviewed the results from 23 research experiments which were
conducted over the past four years at universities throughout the United States, Germany
and France. In each study, separate groups of chickens, dairy cows, beef cattle and sheep
were fed either genetically modified corn or soybeans or traditional corn or soybean as a
portion of their diet. |
Increases herbicide residues in the food because the herbicide is applied later in the growing season and closer to harvest |
The issue of spread of antibiotic resistance from GM crops containing antibiotic resistance marker genes is unproven. If it is a problem at all it is likely to be small compared with the induction of antibiotic resistance through profligate use of antibiotics in animal nutrition, veterinary and medical practice. | Spreads antibiotic resistance to micro-organisms in the environment, and then to pathogenic bacteria. |
More profit for the farmer, seed producer and biotech company shareholder. | No demonstrable benefit to the consumer. In 1999 Deutsche Bank issued a report advising investors to avoid investing in GM crop technology (agribiotech). |
Crops producing nutraceuticals can be
engineered, i.e. food additives which have a nutritional benefit bordering on a
pharmaceutical benefit, e.g. modified edible oils. The vitamin content of plants can be enhanced by GM. Plants which previously did not contain a particular vitamin can now be made to produce large amounts of it (e.g. Vitamin A 'golden' rice). The aim of the GM Vitamin A rice project is not to achieve ideal levels of vitamin A intake through this source but to augment the extremely low intakes which lead to blindness and death of hundreds of thousands of people a year (Prof. Dr. Ingo Potrykus, statement, February 2001). |
A balanced diet of fresh fruit & vegetables plus
cereals and protein is all that is necessary. 'Nutraceuticals' are a sticking plaster
(band aid) attempt to remedy fundamentally unhealthy diets. Existing food sources provide adequate daily intakes of vitamins provided they are eaten in sufficient amounts and the vitamins are not destroyed in the processing or cooking. Vitamin-enhanced GM plants are an unnecessary technical solution to a problem which does not exist. Even with Vitamin A GM rice a normal daily intake of 300 gram of rice would, at best, provide 8% percent of the vitamin A needed daily. |
The killer genes of the technology protection system (terminator technology) allows the seed producers intellectual property (patent) to be protected by a biological rather than litigious method. | No seed-saving by the farmer is permitted. The farmer has to pay royalties to the biotech company. This undermines a traditional agricultural prictice and particularly threatens peasant farming in developing countries. |
The increased choice of modern high-yielding cultivars to farmers allows diversification to keep ahead of economic, climatic and plant disease trends. | The possibility of further globalisation of crop varieties that GE offers through the introduction of traits necessary for introduction into new regions of the globe erodes cultural diversity i.e. traditionally, different crops and varieties are grown by different cultures. Genetic engineering works towards global uniformity, i.e. globalisation of Western/Northern culture. There used to be far greater choice of crop varieties for farmers, sometimes hundreds of varieties of a particular crop in a given region, but this diversity is falling at an alarming rate as a result of the industrialisation of farming under pressure from the agrochemical industry. This will be accelerated by biotech agribusiness. |
GE allows the creation of plants that produce vaccines,
pharmaceuticals or enhanced pharmaceutical raw materials.
|
GE is already used to produce pharmaceuticals in micro-organisms in the much safer containment conditions of biotechnology factories. It should not be taken out into the environment thus putting the environment at risk. In any case, much of the pharmaceutical production which would be created is designed to treat diseases caused by industrialisation and urbanisation which could be better treated not by a genetic fix but by changing lifestyles and environment. |
Novel food crops are tested for genetic stability (breeding true), 'substantial equivalence', nutritive properties, toxicity and allergenicity. It is anyway well known that conventional breeding can introduce increased levels of natural plant toxins into a new variety or can modify its digestibility or nutritiousness. Furthermore, certain organic crops have been shown to have higher levels of toxic substances, e.g potatoes. | GE introduces unpredictable toxic or allergenic effects
into food plants (e.g. Brazil nut gene in transgenic soybeans). 'Substantial equivalence'
is a political-commercial concept rather than a scientific one. GM plants are not genetically stable. For instance, the number of copies of an inserted gene changes through later generations of the GM plant. |
This technology is completely new to the insurance
industry. It is natural that insurers will be cautious about it. But when they realise
that the risks are no worse than with introduced alien species which are dealt with by
conventional methods of weed control, the problem of insurance will disappear. No amount of research under containment conditions will reveal how a GM plant will behave when grown en masse in the open field. |
As the degree of escape of genes from GM crops is
unpredictable, they cannot be recalled once they have escaped and they could multiply in
the wild, some insurance underwriters have stated that such risks are uninsurable. There should be a moratorium on experiments in the open until the safety of the GM plant is fully tested under containment conditions. |
Plant pathogens need not be used in making GM plants. The genes can be blasted into plant cells using a 'gene gun' which fires microparticles of metal coated with the DNA of interest. | Plant pathogens such as Agrobacterium tumefaciens (literally 'cancer causing') are used to shuttle genes into plants and viral gene sequences such as cauliflower mosaic virus promoter are used to make the genes express themselves once in the plant. The pathogens could recombine with their natural equivalents in the plant thus risking unpredictable outbreaks of plant disease. |
Bioprospecting has gone on since very ancient times. There is no reason why an organism which just happens to be at a particular location of the globe should be in the sole ownership of the people living there. Agreements can be entered into in order to protect the traditional usages of indigenous peoples. | Steals genetic commons from peasant farmers and indigenous peoples (biopiracy by the rich North, e.g. neem tree & basmati rice) |
Biopolymers can be produced in GM plants allowing the manufacture of biodegradeable plastics (e.g. PHBV, Biopol) which are also sustainable because they are not made from fossil fuels. | The best sustainable, biodegradeable bioplastic is wood. We should simply plant more trees. |
More 'pros' from Alliance for Better Foods |
Genetic engineering of animals
So far as the organisms themselves are concerned, it is only when GE is considered in the context of sentient beings -- animals and humans -- that the real ethical deliberations begin. A good basis for considering how we should proceed with animals is given in the article by Henk Verhoog.
Pros |
Cons |
GE, combined with cloning, can be applied to animals to make valuable pharmaceuticals which cannot be made in other ways. This is particularly useful for human proteins which are produced in animal milk and used in 'replacement' and other therapies (e.g. lactoferrin in cows for treating septicaemia; alpha-1-antitrypsin in sheep for treating emphysema; factor IX in sheep for treating blood clotting disorders). Transgenic adult animals produced by this method show normal health and behaviour. | Dozens, possibly many hundreds of sheep are mutilated
and killed for these experiments. The lambs born are often excessively large or deformed
and those that are not stillborn die when young. Research funds could be devoted towards
finding ways of making the much needed protein pharmaceuticals in micro-organisms. Because
of the extra protein that has to be produced in the animals that have to be kept lactating
optimally they are under constant metabolic stress. In order to minimise contamination from normal pathogens such as viruses, animals used to produce pharmaceuticals will have to be kept in abnormal conditions which violate their telos or intrinsic nature -- this can cause suffering for the animal. |
Animals have been instrumentalised for millennia, e.g.
the horse. Aren't human lives of higher moral value than animal lives? GE of animals is strictly controlled by the cruelty to animals legislation of the country concerned and experimental protocols are carefully scrutinised by teams of experts. |
GE instrumentalises animals. Many countries have a 'yes, but' approach to permitting animal experimentation. Better control of experiments which cause suffering to animals would be achievable with the Dutch model of 'no, unless'. Instrumentalising animals means that they must first be objectified. Many scientists report emotional difficulties with what they have to do to animals. This shows that their objectification is incomplete. |
Transgenic animals can be created so that their organs
can be transplanted into human beings without being rejected by the normal immune
processes (xenotransplantation). This is achieved by genetically modifying the cells in
those organs to 'look like' human cells to the human immune system. Xenotransplantation is
necessary because the demand for organs for transplant is far in excess of the supply from
'donors'. If you are faced with death by heart failure or the offer of a pig heart transplant, which would you chose? |
Xenotransplantation is placing great emphasis on heart
transplants. But the diseased hearts being replaced have become so by lifestyles and diets
which could have been changed in such a way as to avoid the need for a transplant in the
first place. There is a big risk when transplanting animal organs into human beings that
animal diseases and dormant viruses in animal genomes could be transferred to the human
population. Once activated they could cause uncontrollable epidemics for which medical
science has no remedy. How much animal tissue must be transplanted into a human being before they can no longer be regarded as human and conversely, how many human genes can be transferred to, say, a pig before the pig is eligible for human rights? Transplantation in general raises the question: should we prolong life indefinitely simply because we can? |
Transgenic or 'knockout' mice and other animals can be created with altered or missing genes so they can be studied as models of human disease or for testing possible useful drugs. | Many of these animals pass their lives in great pain and suffering. Animals are not good models for human diseases. Furthermore, there is no simple link between genes and disease. For instance when the human retinoblastoma (eye cancer) gene was inserted into mice it produced abnormalities but there were no symptoms of retinoblastoma. |
Cloning, involving the transfer of almost entire genomes (cell nuclei), can be used to speed up the breeding of particularly valuable new varieties, using less valuable animals as surrogate mothers. | Cloned animals have chromosomes which show structural modifications equivalent to adult animals. Thus they are old before their time. 'Dolly' the sheep was 'mutton dressed as lamb'. |
New breeds of farm livestock can be made more quickly by GE with precisely determined characteristics such as leanness of meat or speed of growth. | Transgenic pigs with the human growth hormone gene inserted to make them grow faster were arthritic, ulcerous, partially blind and impotent ('Beltsville' pigs, USA). Producing breeds by GE creates too much wastage and suffering. Transgenic salmon with enhanced growth may escape into the wild, interbreed with wild salmon and so upset the genetics of the wild salmon population that it could be wiped out. |
GE could be used in combination with cloning to save species from extinction thus maintaining global biodiversity. This is already under consideration for the Giant Panda in China. The techniques could also be used to recreate extinct species by cloning the DNA and inserting in suitable host cells. | Saving endangered species or salvaging extinct ones is merely science fiction. It tends to divert attention away from the real challenges to biodiversity, namely the continuing destruction of habitats by human activity. |
Application of genetic engineering to human beings and their health
Please see also our page devoted to the pros and cons of engineering the human germline .
Pros |
Cons |
GE in the form of 'gene therapy' (somatic) could be used to repair damaged or replace missing genes in people who have genetic disorders such as cystic fibrosis, severe combined immunodeficiency etc. The process need not necessarily use infective agents such as adenoviruses as DNA vectors -- the genes can be incorporated into microscopic fatty droplets called liposomes. | Genetic disorders represent a tiny fraction of the total
burden of ill health. A disproportionate amount of available research funding is being
spent on gene therapy protocols yet despite many years of research, none have so far
succeeded. Pathogenic 'attenuated' vectors such as adenoviruses are used to shuttle genes
into patients. One death has already resulted from their use. There is a serious risk that
the viruses will recombine with 'wild type' versions in the body and kill the already
weakened patient. Gene therapy research is especially vulnerable to abuse because it is mostly backed by venture capital. Researchers who are also investors may be tempted to oversell the promise of experiments on patients and keep "adverse events" quiet lest they depress stock prices. |
Gene therapy is being used, as yet experimentally, to treat cancer. Most of the gene therapy clinical protocols are centred on this major class of diseases in the population. The advantage is that the treatment targets only the cancerous cells thus avoiding the 'collateral damage' that is done to other tissues by current radiation or chemical therapies. | Cancer is facilitated by environmental factors such as
carcinogenic chemicals in air, food and water; radiation (ionising and non-ionising) and
lifestyles. Tackling these epigenetic factors will do more to reduce cancer than all the
technical fixes of gene therapy. In cancer, the tumour is merely a symptom of the underlying diseased state. Whilst removing it or halting its growth is undoubtedly a life saver, more effort is needed to look at underlying causes. |
Recombinant DNA technology can be applied to speed up working out the sequences of all the genes in the human genome. Once these sequences are known together with the mutations which cause or predispose to disease cures can be sought by designing appropriate molecules for use as pharmaceuticals. | Human genomics is a continuation of mechanistic medicine to its logical conclusion. It naively conceives the human being as a set of genetic instructions controlling all bodily functions and even the form of the body. Genomics goes with the increasing objectification of patients by the medical profession. The whole human being is really a healthy interrelation of body, soul and spirit (self). Any medical system which fails to take account of this will be confined to treating symptoms rather than treating the whole person. The whole person includes their biography and the particular illness is part of that biography rather than just a property of the genes. |
Recombinant DNA technology can be used in genetic
screening or testing, i.e. testing people's genomes for gene sequences which might later
give rise to genetic disorders. This can also be done in the unborn, e.g. testing for
trisomy 21 (Down's syndrome), gender etc. Any unwanted foetuses could be aborted thus
gradually ridding the population of undesirable traits. These tests are becoming less
invasive, for instance by testing foetal cells which 'leak' into maternal blood
circulation. Where the knowledge gained by genetic screening becomes a burden for the 'patient', non-directive genetic counselling can be offered. The information will be kept confidential in accord with the normal practices of medical ethics. Gene screening can also be carried out on embryos produced for in vitro fertilisation prior to implantation in the mother. This will save implanting embryos with undesired characteristics, e.g. one or other gender. |
There is no effective therapy for most of the genetic
disorders, so it is unethical to offer the tests to patients. Furthermore, when samples
are obtained from the unborn for these tests the invasiveness of the procedures can be
damaging to both mother and foetus. Combining these techniques with abortion is eugenics
by the back door. The effect is to steer the genetic make up of society according to the
desires of the rich and powerful. Genetic disorders are as much a social construct as a difference in genes. We are all disabled in some respect either cognitively, socially or physically. Were society to change its attitude to one of accepting all people as essential parts of what goes to make up humanity, not only would life for people with alleged genetic disorders greatly improve, but also the perception of 'disorder' would melt away. Because Down's syndrome births are preventable the stigmatisation of people who for various reasons have Down's babies is greatly intensified. Whereas, the reality is that Down's children are usually happy and not only bring a ray of sunlight into families but also offer opportunities for family members to develop capacities which they might not otherwise have developed. Non-directive genetic counselling, whether it be professional or non-professional, is an idea which is not attainable in practice. Genetic selection of the unborn is already beginning to lead to imbalance of the male/female ratio in parts of India and China. Genetic testing can usually only give a statistical probability, and then only with varying degrees of accuracy, of developing a disorder. It has very limited predictive basis for the individual actually being tested. Genetic testing could one day be used to undermine the right of couples to reproduce. Some groups have recommended changes to the law to allow people access to genetic information from people to whom they are closely genetically related. This will override medical confidentiality. |
Genes and artificial chromosomes can also be inserted into embryos in a process known as germ-line gene therapy. This could be used to cure genetic disorders, including behavioural disorders such as schizophrenia, or to insert genes which enhance intelligence or athletic performance. The benefits of these genetic changes would be passed on to later generations. | This is eugenics: the conscious engineering of the
genetic inheritance in the human population. The danger is that any errors incorporated in
this way would be passed on to further generations. There is currently no legal way of
preventing such passing on. Experimentation on germ line gene therapy would involve the
creation and destruction of thousands of human embryos (human beings). Such things as intelligence and athletic performance are in any case very complex interactions of epigenetic factors such as upbringing, nutrition, education, experience and healthy living as well as genetic factors involving the networking of hundreds of genes. There are no simple causal connections between genes and behaviour. |
Cloning might one day be combined with GM to create
babies designed to meet the wishes of the parents. People could clone themselves or even
lost loved ones from their DNA. Sperm and eggs from attractive and intelligent people are already offered for sale, including on the Internet. Cloning would be merely a small extension of this to ensure that the product meets the customer's wishes.
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Creating so called 'designer babies' would be pandering
to the unbridled vanity and selfishness of the parents. The individuality coming into the
world would be an instrument of the parents' desires. It is not unlikely that children
will sue their parents for wrongful genetic selection. Cloning oneself would be egoism made manifest. Furthermore, recreating exact physical copies is not a guarantee that the same individuality will be recreated. Different individualities shape the form and function of their physical bodies according to their needs, inclinations and desires, such that in the course of time these bodies even grow to look different. Cloning applied to humans would be one further step in the commodification of human beings which is already happening with human tissues and organs. Clones are already proving to be old before their time and animal experiments show that it is highly wasteful of eggs and embryos. Hundreds are needed for one successful clone (277 in the case of Dolly the sheep). |
'Therapeutic cloning': If the law gives the go ahead,
cloning could almost immediately be used in conjunction with GM to create artificial human
cell lines from embryonic tissue (stem cells) that could be used for transplantation (e.g.
in Alzheimer's or Parkinson's disease), for the production of pharmaceutical proteins etc
and for medical research. Experiments in animals show that future therapeutic cloning of human tissues for implantation could take place without involving an embryo stage. This would remove a major ethical objection to human cloning. |
Foetal (stem) cells created in this way are totipotent, i.e. they could, in principle, develop into whole human beings. It is immoral to bring potential human beings into the world as instruments for the medical treatment of others. They would be slaves in the truest sense. Already, thousands of human beings 'waiting fully to manifest' are stored as deep frozen embryos all over the world. In the UK in 1998 thousands had to be destroyed. |
Genetic disorder support- and pressure-groups, often set up by parents with affected children, know from first hand experience the extent of the suffering which both patient and family often undergo. They know best how urgently the new GE technologies are required by the patients they represent. | The combined availability of genetic screening followed by abortion on demand, gene therapy (germ line and somatic) and cloning threatens to make people with genetic disabilities into more of an underclass than they already are even in wealthy societies. |
Recombinant DNA techniques can be used for 'DNA fingerprinting'. This forensic technique allows the precise identification from samples of hair, blood, semen or skin of individuals who were present at the scene of a crime. | DNA fingerprinting is merely one tool in the forensic scientists tool-kit and like other forensic techniques is open to error, misinterpretation and deliberate falsification of the evidence. Because of its power there is a tendency to put excessive reliance on it and this can lead to wrongful convictions. It should therefore be used in conjunction with other means of corroborating the evidence. |
Gene screening will enable insurance companies accurately to assess risks and therefore set premiums; employers to determine precisely the suitability of a person to work in a particular job, e.g. excluding people with genetic susceptibility to hazardous chemicals. | Gene screening will create an insurance and employment underclass. It will be used to give 'scientific' justification to social discrimination' A proper social concept of insurance is to spread risk evenly across members of a society. Modern premium loadings or refusals of insurance are undermining this. Adverse insuring, i.e. by people who know they carry a risk, can be accommodated in levels of compensation on the basis of risks and needs in the population as a whole. |
GE and cloning could be so successful in the future that old age, illness and death will be historical curiosities. | Life is a cyclic process which is consantly unfolding. Death, decay and renewal are essential parts of it. Human GE and cloning seek to short circuit the process and fix human beings as they were at a particular point in time. GE is thus backward-looking, or past-orientated. Ageing, illness and death are parts of human biography. Seeking to eliminate them denies human evolution and what the future will bring. |
Contents
#Genetic engineering in general
#Genetic engineering of plants (crops)
#Genetic engineering of animals
#Application of genetic engineering to human beings and their health
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