Genetically Modified Organismes (GMO)
Ethics of Genetic Engineering
Genetic engineering has been a catalyst for discussion of ethical issues related to the modification of nature, and has been politically contentious because of the economic importance of the food industry.
This chapter aims to introduce:
- Basics of genetic engineering.
- Examples of genetically modified organisms (GMOs) and the purposes for which they are made.
- Ethical issues of genetic engineering.
What are genetic engineering and GMOs?
With many years of research, scientists have now discovered to some extent which genes do what functions in building organisms. With the help of this knowledge and new developments in scientific technologies, they are able to modify the genetic constitution of organisms for various purposes through genetic engineering. Genetic engineering or genetic modification is an all-inclusive term to cover all laboratory and industrial techniques used to alter the genetic constitution of the organisms by mixing the DNA of different genes and species together.
Genetic engineering or genetic modification is the process of recombining DNA. The living organisms made with altered DNA are called Genetically Modified Organisms (GMOs). However, the process is not so simple as precisely cutting out one gene and putting it into another place in the DNA, since genes are surrounded by other sequences in the DNA that determine whether or not a gene from one organism can function in another organism. So a careful study of the GMO is needed to be sure of its safety. Genetic engineering can be used for good causes. However, it can also potentially be misused.
Genetic engineering is considered special because often the techniques involve manipulating genes in a way that is not expected to occur ordinarily in nature, allowing characters to be changed, not just between the species but also between kingdoms. Technology is rapid and new ways of manipulation and experimentation are being made. Also it can be applied to the human species (see the Gene therapy chapter).
- Q1. Can you describe any examples of genetic engineering you have heard of?
- Q2. Give examples where you think the environment can influence the functions of the genes and the behaviour of organisms.
- Q3. Find the institutes in your area doing genetic engineering. In which areas are they researching and why?
Examples of genetic engineering in medicine
Many human proteins are now being commercially manufactured by the use of gene transfer to microrganisms such as bacteria or yeast, including blood clotting factors, interferons, lymphokines, growth hormone, erythropoietin, insulin and various growth factors, all of which have medical uses. One of the most common proteins in use is human insulin for diabetics, which has been licensed for many countries to use since 1982.
Recombinant DNA techniques are also being used to produce human vaccines, for example to produce cheap, easily stored vaccines against major childhood diseases. The logistics of the world-wide immunisation programmes are influenced more by transport, storage and delivery than production. Edible vaccines have also been made as foods, such as hepatitis B vaccine in lettuce or banana (or Plantain), which may avoid the need for medical staff to administer the vaccine, and make the plants cheap enough for third world countries. The degree of expression is not yet high enough for effective use, but is being improved.
A genetically engineered vaccine against cattle ticks is being mass produced in Australia, that should help control tick infestation. The tick is an external parasite, but ingests blood, and the vaccine is a modified version of a tick protein from the gut cells, which produces an immune response in the cattle which in turn prevents reproduction of the tick.
Modified proteins can also be made, using genetic engineering to alter the catalytic properties of natural enzymes, a process known as protein engineering. Many pharmaceutical products can potentially be made. The medical importance of these recombinant DNA protein products is growing, and the availability of these products makes therapies for a lot of previously untreated or uncured diseases possible.
Already there are successful attempts to transfer human genes which incorporate useful proteins into sheep and cows milk, so that they produce, for instance, the blood clotting agent factor IX to treat hemophilia or alpha-1-antitrypsin to treat cystic fibrosis and other lung conditions, also naturally occurring polyclonal antibodies for which at present there are only human donors.
Genetic engineering in medicine has been long researched for transplantation purposes, for example, to make organs or body parts like valves for the heart from pigs. There are still safety concerns about large organ transfer from other species (xenotransplants). The most controversial form of genetic engineering in medicine is the use of cloning technology to create organs for transplantation purposes so that they are immunologically compatible.
Q4. Do you know anyone who has diabetes? If you had a type of diabetes that could be treated by a daily injection of human insulin made by genetic engineering what sorts of side effects might happen from the treatment?
Q5. What do you think of genetically engineered vaccines taken through food rather than by injections?
Q6. Should we use cloning for organ transplantation?
Environmental use of GMOs
Bioremediation is a natural process occurring very slowly in which the bacteria and other micro-organisms breakdown oil into other harmless molecules.
Oil spills and oil in waste discharged into the sea from refineries, factories or shipping contain poisonous compounds that are dangerous to the welfare of all living beings, including plants and animals. With environmental pollution on the increase, scientists are developing genetically modified bacteria that can effectively and rapidly digest oil and that are well suited to particular environmental conditions. Others are used to remove algae from ponds and lakes, or to manufacture useful chemicals such as enzymes for plants or to provide renewable resources to make industrial chemicals from.
GMOs for environmental clean up have been used in various parts of the world. Not many ethical concerns have been raised against this purpose. However, what is interesting is that natural genetic engineering done by gene exchange between bacteria in the soil or water makes many different bacteria selected to use toxins for their energy source, and these bacteria are better suited to local environments. So usually by adding fertiliser to a polluted area, the already existing bacteria will be able to grow well and clean up the pollution instead of having to introduce new ones. There is still more research needed, but it shows that in nature genes exchange between different organisms, especially rapidly in microorganisms (against the general rule of inheritance discussed in section C1.1).
Q7. What kinds of genetic changes to organisms do you think would be helpful or harmful?
Q8. What kinds of genetic and non-genetic technologies and methods are alternatives which may be used to improve environmental conditions?
Ethical Concerns over Genetic Engineering
Given that the technology is new, has immense potential, is rapidly developing, and can be applied to all living beings, it can be used for beneficial purposes but there are also risks. It is a sophisticated technology and needs developed laboratory facilities and particular environmental conditions that require investment. Many kinds of GMOs are developed for environmental purposes and for health and medicine. Genetic engineering has been particularly successfully used and applied in food and agriculture to produce genetically modified foods (See a separate chapter C3).
Because genetic engineering is still considered a new technology, some doubts, fears, concerns have been raised. Let us consider extrinsic ethical concerns and intrinsic ethical concerns.
a) Extrinsic concerns are based on doubts about the technology, its potentiality, newness and applicability to all life forms. There are fears of human misuse of technology, for example for biowarfare or eugenics. There are fears of environmental damage to other organisms or ecosystems. The people in favour of technology think that genetic modification provides a great opportunity for feeding people or treating sick persons with new medical products. The novelty of the technology is one of the reasons people think there are many ethical issues, as they have concerns about health impacts and other potential dangers. In addition, there are concerns about the centralization of economic control over living things, such as the patenting of life.
b) Intrinsic concerns are based on how people view life, nature, religion, their personal emotions and values. There is a feeling that mixing up genes in the organisms for our use is “Playing God” and human beings should not intervene in God’s realm. Crossing natural species boundaries is creation of new life forms and inventing a new world through technology. Genetic engineering disrupts the beauty, integrity, balance of nature and might harm life. However, at the same time we can say that concrete cities and high tech medicines involves playing God, and agriculture was started by disrupting nature. Also hybrid plants and animals like mules are cross-species organisms which have existed for many years. In fact mules have been cloned and can reproduce in that way!
There are fears that it could be misused for cloning human beings or making genetically enhanced “designer babies”, so that parents can select, chose and improve the characteristics of their babies like blue eyes, fair skin, tall, boy or girl, etc. However, the success rate of cloning is very low and its applications are still in very early stages of research. (See later chapters on human gene therapy and on cloning)
Q9. Please write down your own ethical concerns about genetic engineering.
Q10. What is “playing God”? How much do you interfere with nature in your daily life?
Q11. Is it good for society to be cautious in the use of new technology? Can you think of existing technologies which are harmful?
Environmental Risks of GMOs
During 1973-1976 there was a voluntary moratorium imposed by scientists on the practise of introducing foreign DNA into bacteria, following an International Conference in Asilomar, California. The fears were that moving genes widely could have bad consequences, for instance it could cause the spreading in the microbial world of antibiotic resistance, or toxin formation; or that genetic determinants for tumour formation or human infectious diseases would be transferred to bacterial populations, which could then infect human beings. After discussions there was a declaration and development of levels of risk for different types of organisms, for example, so that dangerous pathogens would only be used in the highest level of biosecurity containment.
Both physical and biological containment are used when we do not know the environmental or health safety of a novel organism. “Biological” containment advocated the use of “crippled” host cells and vectors, such that these would have no success in colonising any environment outside that of the contained laboratory even if they managed to escape from it (e.g. E. coli K12). Since the initial categories of physical containment were decided upon there has been widespread experience gained in the practise of these experiments, which has resulted in a decrease in the assessed hazards and thus the type of containment judged necessary. The principle of biological containment is still used for most laboratory experiments, especially when dealing with human genes and/or tumour-promoting agents. Physical containment is not so strict, but is still maintained for work on tumour or disease-promoting agents.
Q12. If you read the book or saw the movie Jurassic Park, can you describe what methods of biological containment and physical containment were used to control the genetically rebuilt dinosaurs? (See also the Movie Guide)
Before the appearance of genetically modified organisms (GMOs) there have been harmful effects from some of the accidental releases of organisms from laboratories. In 1958 tobacco blue mould (Peronospora tabacina) was brought into the UK for a research institute. In that year the mould spread to four other institutes, including one in the Netherlands, and to a commercial tobacco crop in England. In the following year the disease appeared in the tobacco fields of Belgium and the Netherlands, from where it spread quickly across the rest of Europe (advancing in Germany at the speed of 5-20 km per week). After several years of crop breeding resistance was increased, but it is a powerful example of the risks of accidental release of new organisms.
There are many more common examples of ill effects from the introduction of novel species into Australasia, for example rabbits and cane toads. The deliberate environmental introduction of any new organism, including GMOs, should be only undertaken within a framework that maintains appropriate safeguards for the protection of the environment and human health. Natural habitats already contain their own indigenous populations of organisms, organised in a delicate web of nature, which needs to be maintained. Recent introduction of biological pest control agents has been more successful due to better ecological assessment. We should also note that most food crops and ornamental plants are introduced species, although they are also essential for the economic prosperity of most regions of the world.
The environmental release of genetically modified organisms (GMOs) is now assessed by regulatory authorities and trials are common in many countries. Only small scale agriculture can be conducted in semi-closed environmental systems, though some important products used today are produced in that way, such as eggs from battery farming of chickens (which raises ethical questions of farming methods). There have been many field trials since 1984 when Canadians field tested a transgenic plant. There is public concern about the free release of recombinant organisms into the environment, and the degree of care required depends on the potential risk to the ecological balance and humans. Scientific methods and experiments are being used to look at the risks, which include gene transfer and the cross-breeding resulting in new weeds. These are sometimes called “superweeds”, if they include genes for tolerance to herbicides. International transport of GMOs is regulated by an international Convention, the Cartegena Protocol to the Convention on Biological Diversity, which entered force on 11 September 2003.
Q13. Can you think of any species that were introduced by human beings into your country? Do they have positive and/or negative effects on your society, economy and environment?
Genetically Modified Foods
Since 1995 people in the U.S.A have routinely eaten food made from plants that have been modified by genetic engineering. The economic importance of the food industry is one of the reasons why some other countries have placed limits on import of genetically modified (GM) food, as well as health concerns to the public.
This chapter aims to introduce:
1. Issues of genetically modified food.
2. Ethical issues of labeling genetically modified food.
Genetic engineering and Food
Genetic engineering or genetic modification alters the genetic constitution of organisms by mixing the DNA of different genes and species together. The living organisms made with altered DNA are called Genetically Modified Organisms (GMOs). Genetic engineering is considered special because often the techniques involves manipulating genes in a way that is not expected to occur ordinarily in nature, that characters can be changed between species.
Many kinds of GMOs have been developed for environmental purposes and for health and medicine. Genetic engineering has been particularly successfully used and applied in food and agriculture to produce genetically modified (GM) foods.
Use of genetic engineering technologies in food and agriculture to produce GM food has been very controversial. Genetic engineering has been used to produce transgenic plants that carry several enhanced characteristics by inserting genes from various organisms, for example, plants with increased yield, disease resistance, and pest resistance with inserted Bacillus thuriengensis (Bt) insecticidal protein genes which selectively kill pests that eat crops. There have also been fruits and vegetables modified for long term storage or delayed ripening that remain fresh for a long time, which is also useful during transportation to the market. Over 15 countries of the world used GM crops for general food production by 2004.
In 1996 a new tomato variety was sold in the U.S.A. made by a technology involving use of antisense RNA sequences to bind to the mRNAs of undesired proteins. The concentration of an enzyme (poly-galacturonase), which is produced by ripening tomatoes causing softening of the tomato, was reduced by up to 99%. This enzyme degrades the cell wall in the tomato, so its absence leaves the fruit firmer longer. These tomatoes have been developed to improve shelf life (about 300% longer) and taste since growers can leave the tomatoes on the plant longer. It is also useful to transport to the market, especially in developing tropical countries where it is very hot. The so-called tasty tomato, Flavr Savr (Flavour Savour), was not however very commercially successful when sold in supermarkets in the USA.
The second wave of GM plants includes those with high nutritional content and improved food quality like golden rice, or plants that can tolerate high salt levels in the land or are modified so that they can grow in harsh conditions like drought. Some GM food such as golden rice or bananas with vaccines are being developed for health purposes. Golden rice has increased levels of beta-carotene, considered to be especially beneficial for people with vitamin A deficiency.
Q1. Are there any GM foods in your country?
Q2. Which food in the supermarket is not modified in some way?
Q3. What other benefits can you think of from tomatoes which do not go soft quickly? What other agricultural uses of genetic engineering do you know?
Q4. Do you think golden rice is a “good” GM food? What other information do you need to make a judgment?
Ethical issues of GM Food
Some people think that products made from GMOs are unnatural. Some call them as Franken-foods. We need to think about whether they are different from existing food varieties. It is not possible for the consumer to differentiate GM food from other conventionally grown foods since both look the same, may even taste the same, unless it is mentioned on the labels of the packets. It is difficult to say that the food is unsafe given that in some parts of the world, like in the USA, people have been eating GM food for a decade. In other parts of the world, especially in Europe, many people are not willing to accept GM food because of fears of health risks and other ethical concerns.
We can find people with allergies to many foods, and there will always be some people who have an allergy. That is another reason why people may need to know what is in the food. In the modern supermarket however, most foods are processed containing some compounds from many different plants, especially soybeans.
In the USA, the Food and Drug Administration (FDA) has said it is not necessary to label food containing products of genetic engineering. This is against the views of many public groups who argue that it is best to have more information available for the consumer and that food origin is of interest to consumers. In Europe or Saudi Arabia for example, any food with more than 1% from each GMO must be labeled, and in Australia, Japan and New Zealand it is any food with more than 5% from each GMO.
As discussed in the chapter on genetic engineering we can consider these types of concerns as extrinsic ethical concerns. The people in favour of technology think that genetic modification provides a great opportunity for solving hunger, food insecurity, and malnutrition in the world since it can be made for all environmental conditions and help in increasing quantity and quality of food. It is these arguments which have led the United Nations Food and Agriculture Organization (FAO) and United Nations Development Program (UNDP) to support the selective applications of genetic engineering for food production. At the same time, there are fears raised about the safety of the food and risks to health since it is considered a new technology and people fear that some genes will be transmitted to them.
Many NGOs in the world have also raised the concern that growing genetically modified crops will be harmful for the environment and genetic modification will result in “superweeds”. For example, if herbicide resistance genes from canola will flow into weedy relatives to make them resistant to herbicides. Scientific studies are still being conducted to evaluate the actual risks.
It is also said that GM crops are unsafe for other organisms that feed on them, for example, some people claimed Bt toxin kills Monarch butterfly larvae. Extensive scientific studies found this was not true, however, these stories are still found on the Internet and in some NGO circles. In general farmers growing Bt crops use less pesticides and less dangerous pesticides than they used to use in “conventional” agriculture. This can be beneficial to the environment, especially if GM can target specific pests more effectively than the broadly toxic pesticides which devastate many non-pest invertebrate groups.
There is a fear that GM crops and foods will result in the loss of our biodiversity. Also, since the technology is new and needs lots of investment, it would be unfair to small farmers in poor countries. These are valid concerns and demand scientific investogation. However, the scientific studies have not been conclusive, and there may be benefits in some environments and societies and not in others. There have been contradictory reports both in favour of and against genetic modifications which are confusing people.
Q5. Do you think GM food will be an appropriate method for eradicating hunger and malnutrition from the world? How else can we eradicate hunger and malnutrition in an ever increasing global population?
Q6. What is a safe food? Would you eat GM food?
Q7. How much information should be on food labels? Bring some examples to class to discuss.