Topic 1 - Genetic modification Flashcards
What are the 3 broad concerns or worry that GM products might be detrimental to human health?
There are at least three broad and overlapping areas of concern about GM crops. First, there is the very significant worry that GM products might be detrimental to human health. This includes concerns that:
The use of antibiotic marker genes might increase bacterial resistance to antibiotics.
New proteins manufactured in GM crops might provoke unwanted allergic responses.
Novel combinations of genes might have longer-term human health effects of an uncertain nature and severity.
Give some examples of potential environmental effects that crops have on the environment?
Second, there are concerns over potential environmental effects. Examples may include the following:
Insect-resistant crops may adversely affect benign insect species (so-called non-target species).
The adoption of herbicide-tolerant crops might encourage farmers to use greater quantities of broad-spectrum (non-specific) herbicides, with resulting detrimental effects on wildlife.
Genes might spread from the crop plant to wild relatives, to produce herbicide-tolerant weeds that are far more difficult to control; or insect-resistant weeds, which might affect a much wider number of non-target species.
Give some examples of broad political concerns of GM crops?
Third, there are a number of broadly political concerns. For example, there is the anxiety that GM crops are only one step further in the industrialisation of agriculture. By this logic, it could be that much of the dislike of GM crops stems from guilt by association; they are produced by agrochemical and seed companies and they are an element of ‘non-traditional’ farming. There are also real concerns about the level of economic control these large, frequently multinational, companies would have over our food systems if farmers worldwide became reliant on GM crop varieties.
What does peer review mean?
Peer review is the crucially important process at the heart of communication within the scientific community. Scientists submit research papers to scientific journals; the journals then recruit anonymous experts in the same field to thoroughly check the work before it is published.
The following card will inform you of different types of ways of communicating with the public.
Now think about the three items you read and watched. What strikes you about the style of communication, the approach taken to explain the issues, or the use of scientific evidence to back up any specific scientific claims made? Make some notes in the response box below to address these issues.
In Video 1.1, Shiva deliberately uses emotive language to tap into potential listeners’ existing concerns. It is clear that she has strongly held views on the issues and it is obvious what these are. In this context there is little attempt to back up statements with facts and where facts are given they are not corroborated (the source given). This is entirely appropriate for the role her video plays on a campaigning website, but it is not an impartial source of information. The language used is simple and accessible to all.
In the opinion piece in The Conversation the two authors use journalistic language to refute specific claims made by anti-GM campaigners (and Shiva in particular). The language used is reasonably accessible. Here too there is a clear sense of the authors’ opinions as pro-GM supporters and there is a feeling of a ‘campaign’ where the authors attempt to influence readers’ opinions. There is a greater amount of scientific fact (than in Shiva’s video) presented and this is referenced to other printed articles, which can be checked by the reader.
The piece in Nature is also written with a journalistic style but with a more specialist audience in mind. Although still accessible to the interested public, it is a tougher read than the other pieces. It is referenced to other journal articles and to some original peer-reviewed scientific papers and it includes specific data from reliable sources. The article in general presents argument from both sides of the GM debate on three key issues and draws on evidence. It tends to point out that conclusions on certain issues are not clear-cut where evidence is lacking.
Next is a card following my response on what i think of GMO crops?
1 Concerns about GM crops
Note down your opinions on GM in general here. You might like to revisit these notes when you have completed this week’s study.
Your response:
I can understand the reasons behind GMO crops and the need to do it. I feel it would only be an option for the wealthy farmer as you would need the funds to invest in the crops initially and keep on top of the herbicide products. There must be the gain to the farmer in terms of profit otherwise they wouldn’t do it. This means that the smaller farms would have to sell their crops for less if the bigger industrial farms are producing alot. The crops that contain pesticide is beneficial to the environement as it means less pesticides is put in to the environment. I would be against it because its not something that I would want to put in to my body and the full effects on the body are not yet understood. Forcing genetics into crops is not natural and surely this would affect the person or animal consuming it. People in third world countries would not benefit from this and would actually be at a disadvantage because they would also have to sell their crops for less. Although the idea is to feed more people it is not feeding the people that need it.
By applying lots of herbicide to herbicide resistant plants super weeds are created much quicker than what would happen naturally, so more herbicide needs to be used which costs more money, smaller farmers and poor countries will not benefit from this.
Suppose that a disease-resistant rice plant could be obtained either ‘naturally’ – i.e. via conventional plant breeding – or via the ‘engineered’ route. Which would be more acceptable to you and why?
Your answer might be one or the other, both, or neither. This is not a question anyone else can answer for you. However, do make sure you have written down the reasons underpinning your choice; it will be useful to come back to them later on. Do you think your choice is based on logic or feelings?
I would say naturally because I feel this is made to its purest form without any intervention but if the chemical components are exactly the same engineered then there is probably no difference.
Would you say modern foodstuffs are natural or unatural?
It is perhaps overly simplistic to take the line that only natural foods should be commended and that GM plants are unnatural. Arguably, very few of our modern foodstuffs can be termed natural, as they are not derived from naturally evolved crops. Tremendous changes in genetic make-up have been achieved by conventional (i.e. non-GM) breeding methods. As you learnt in Week 1 of this topic, traditional plant breeding involves selection of individuals seen as superior, and then crossing; that is, transferring the pollen of one superior plant to the female parts of another superior plant of the same species. Whilst those suspicious of GM crops do not argue against this form of production of new crops, it is hard to argue that it is in any way natural.
What is intraspecific or withing species breeding?
So far in this topic, plant breeding has been discussed in terms of intraspecific or within-species breeding; that is, crossing plants of two varieties from the same species.
How could you argue that intraspecific or within species breeding is natural?
It is possible to argue that this type of cross-breeding could at least have some chance of happening naturally in the environment by normal pollination methods. More recent plant breeding methods include interspecific and intergeneric crosses.
An organism is classified as living if it is capable of breeding with one another describe how the latin name helps to identify this.
Recall that living things are classified into groups based on the observable characteristics they share with other organisms. A species is defined as a group of organisms capable of breeding together to produce fertile offspring and is denoted with a Latin name consisting of two parts. The first name is the genus that the organism belongs to and the second name denotes the exact species within that genus.
The scientific name for the maize (corn) plant is Zea mays. What genus does this species belong to?
The genus is Zea. Species that belong to the same genus have lots of similarities but they are not sufficiently alike to successfully breed together under natural conditions. If you need further refreshment on scientific classification and the binomial naming system, then go to the relevant section of the Primer.
Within the genus Zea there are in fact five species of which Zea mays is just one.
Suggest what the term interspecific breeding means.
Cross-breeding plants from different species, so in the Zea spp. example, this would mean artificially crossing plants from two of the five different species together to produce hybrids.
What is intergeneric breeding? give an example?
Intergeneric breeding crosses plants from different genera (plural of genus). These plants are even more dissimilar from each other than plants from different species but can be artificially bred together to produce a range of so-called man-made crops. One example is Triticale (Figure 2.1), which is a hybrid between wheat from the genus Triticum and rye from the genus Secale. Triticale is used in animal feeds and (without any level of public concern) in the manufacture of multigrain bread for human consumption.
What is haploid breeding?
Haploid breeding (also known as doubled-haploid breeding) involves the treatment of normal (diploid) plants so as to produce haploid offspring, which have only one chromosome from each pair in the nuclei of their cells.
What are chromosomes and what is their role within cells?
The chromosomes consist largely of molecules of DNA. These store the cell’s genetic information, which instructs the cell how to make specific proteins. Chromosomes are found in the nucleus of every cell and their number is characteristic of a given species. Ordinary plant and animal cells contain the diploid number of chromosomes, where the chromosomes are found in pairs. Gametes (sperm/pollen and ova) contain a single set of unpaired chromosomes and this is the haploid number. If you need to revisit these concepts, go to the relevant section of the Primer.
How are haploid crops produced?
The haploid plants are treated with a chemical that induces each single chromosome to double, producing an identical copy. This means that the plant is homozygous for all traits. The method produces true-breeding crops more quickly than traditional plant breeding, and commercial varieties of around 300 plant species, including barley (Figure 2.2) and maize, have been produced in this way.
What is mutation breeding?
Mutation breeding is a technique that involves exposing crop plants to appropriate doses of ionising radiation, or another mutagenic agent. This increases the rate of mutation, and may knock out one or more genes.
Almost all of the resulting mutations are deleterious, and lead to unhealthy and/or infertile plants. Occasionally, a previously unknown feature, such as disease resistance or high yield, arises that may be beneficial, and this can be exploited and a new strain developed.
How common are mutated crops (through mutated breeding)?
Mutant varieties of crops are used throughout the world. In China, three mutant rice varieties cover more than 30 million hectares of agricultural land. And in the USA, the mutation-bred ruby red grapefruit, selected to be sweeter and darker in colour, is a massive commercial success.
It has been estimated that more than 32 000 improved crop varieties in more than 200 different species (e.g. see Figure 2.4), have been developed through mutation breeding in the past 50 years, with no evidence of public concern and with very little regulation. Indeed, the current regulatory environment controlling the introduction of new GM crops is driving many biotechnology firms back to this old staple from the biotechnological toolbox`
What is marker assisted selection and how is this a step up from traditional methods?
Marker-assisted selection (MAS) is a relatively new technique that uses sophisticated genetic and biotechnological techniques to detect new varieties of plants with useful traits. It relies on an indirect selection technique, which follows the inheritance of a selected marker associated with the desired trait.
Using traditional techniques, finding varieties of a crop plant possessing the characteristics the plant breeder is interested in was a slow and expensive process. For example, looking for rust resistance in wheat would involve growing hundreds of plants, infecting them with rust, then selecting those plants most resistant to the disease and using them for further breeding.
With MAS the idea is that a specific, measurable marker is associated with the inheritance of the trait the plant breeder is interested in; in this case, rust resistance. Frequently, DNA-based markers are selected. These are easily identifiable genes that are located in close proximity, on the same chromosome as the gene or genes thought to govern rust resistance. Being located close to the genes of interest for rust resistance means there is a very good chance they will be inherited together from parent to offspring. Recall from previous studies that the closer two co-located genes are on a chromosome, the greater the chance of them being inherited together. See the relevant section of the Primer for a refresher on this. Hundreds of seedlings of different wheat varieties can therefore be cheaply and quickly screened for the presence of the marker in the laboratory; there is no need to grow the plants to maturity and check for rust resistance in the adult plant, since the presence of the marker indicates that the seedling is likely to be rust-resistant. If the marker cannot be found in a seedling, then the plant is discarded.
How can marker assisted selected crops be beneficial to the environment?
MAS is already reaping significant rewards. The first drought-tolerant rice variety, MAS 946-1, nicknamed aerobic rice, developed via MAS was released to the market in 2007. It was a product of cross-breeding between a deep-rooted variety of Japonica rice from the Philippines and a high-yielding Indica variety. The plant requires 60% less water than former varieties. Unlike many rice varieties, it doesn’t need to be planted in paddies, with its roots submerged in water. So it is perfect for growing in drought-afflicted countries or where groundwater supplies are overexploited. The development team at the University of Agricultural Science, Bangalore (Figure 2.5) claim that aerobic rice uses 3000 litres of water less than other varieties for every kilogram of rice produced.
Why is the breeding of these types of drought-resistant crop plants so crucial?
With the onset of climate change, new varieties of crop will be required to withstand more extreme environmental conditions. As you will see in Topic 2, water will become an increasingly scarce resource in parts of the world where food is grown today.
What is distinctive about GM as opposed to these more orthodox methods of plant breeding?
It can bring about the selective and specific transfer of one or more genes from one species to a radically different organism.
What is the downside to more convetional plant breeding?
With more conventional plant breeding, crossing generally requires the combination of two entire genomes. This means that in addition to what may be the single gene of interest, others are brought along in the process, as many as 30 000 from each parent. Take a conventional wheat-breeding programme, where the intention is to introduce a foreign gene from a distantly related cultivar into an existing commercial cultivar. By conventional crossing, not only would the new useful gene be introduced, but also a whole range of other genes. The overwhelming majority of these new genes are unlikely to be advantageous to the cultivar. Some could bring unintended disadvantages. Recall from Week 1 of this topic how time-consuming repeated backcrossing is to dilute in the offspring the effect of deleterious genes from the distantly related cultivar.
What is meant by the term ‘reductionist mode of thought’?
A reductionist mode of thought is one that argues that complex phenomena can be explained by analysing the system at a more basic or simple level.
What do critic of GM argue in terms of changing genes?
Critics of GM claim that the process involves genetic transformation of a type and degree that is unprecedented. They emphasise factors such as the extensive breaking and joining of the DNA of the host genome and what some call illegitimate recombination and scrambling of both foreign and host DNA at the points where transgenes become inserted. By this logic, GM technologies are imprecise and inefficient. It is claimed that removing genes from their normal context and randomly inserting them in a totally new genetic environment could lead to position effects, resulting in variable levels of transgene expression as well as disruption of host gene function. Critics of GM claim that many of the enthusiastic proponents of GM are following the traditions of genetic determinism and adopting simplistic reductionist modes of thought about the science of genetics
What two committees have to assess GM crops to be field tested?
In the UK, for a GM crop to be even field-tested requires assessment by two committees: the Advisory Committee on Releases to the Environment and the Advisory Committee on Novel Foods and Processes. Before commercial cultivation, the trial results are examined by the European Food Safety Authority, and member states in the European Union have the opportunity to veto any crop on any grounds
What is the only GM crop to be approved in Europe?
Only one GM crop has been approved for use in Europe since 1998. (This crop is Bt insect-resistant maize; 90% of all the Bt insect-resistant maize grown in Europe is grown in Spain.)
Even though the growing of GM is banned in UK and europe. HOw do they get in to our food system?
It may come as a surprise to note, however, that GM animal food (soya bean in particular) is freely imported from parts of the world where GM crops are approved, and fed to European livestock.
What may the political considerations of GMO food in europe be?
Public opinion in Europe in 2015 is firmly anti-GM, so political parties proposing relaxing GM-related regulation risk losing their popular support.
Why do anti GM campaigners approve of marker assisted selection?
How do anti-GM campaigners feel about non-GM biotechnology? Greenpeace and GeneWatch UK are currently vigorously endorsing marker-assisted selection (MAS) as a superior alternative to genetic modification. They believe that because MAS can be used in a way that respects species barriers (meaning that no genes are transferred between species), it is both ethically sound and as safe as conventional plant breeding. Many scientists working in this area feel that MAS and GM are on the same technological continuum; they rely on the same techniques in genetics and molecular biology and find it bizarre that the regulatory framework treats the products of these two types of related breeding programmes in a completely different way.
What is likely the most deleterious effects of GMO’s?
It is likely that most deleterious effects of genetic modification, like those of conventional breeding, result in unhealthy or infertile plants, which are not developed further. Commending natural sexual reproduction methods above others might be seen as being more problematic. Natural processes are often error-strewn and may give rise to unexpected outcomes.
Why do some GM critics believe it is wrong to interfere with nature at all?
For some GM critics, however, the premise that other methods of selective plant breeding are not truly natural either does not hold much sway. Many believe that it is intrinsically wrong to treat the natural world in an industrial fashion, focusing on our needs and wants, even if the outcome is broadly beneficial. Such anti-GM campaigners view the environment as an object of ethical concern and feel that any interference is morally wrong. This resonates firmly with the idea of sustainability and sustainable agricultural practices, with the overriding aim to ensure that the environment is undamaged for future generations of both people and other species.
The 1999 report of The Nuffield Council on Bioethics, Genetically modified crops: the ethical and social issues, suggests that what guidelines should be followed reagrding ethical priciples when considering the evaluation of any new technology and its benefits and risks?
This report suggests that it is important to be guided by the following ethical principles when considering the evaluation of any new technology and its benefits and risks:
The principle of general welfare: governments and policy-making institutions should act in the best interests of the citizens.
The principle that people’s rights should be maintained – for example, the right of consumers to have freedom of choice as consumers.
The principle of justice: both the burdens and the benefits of particular policies and practices should be shared fairly between those affected.
If you were to apply these principles to the GM debate, this would quickly raise the question: would the new technology increase food security for the global population? What other specific questions would you need to ask to help determine if the three principles were adhered to by the implementation of GM technology?
The Nuffield Council on Bioethics in their report (1999) selected the following broad questions around GM technology. You may have included some of these or thought of others:
Will the technology promote general human welfare, for example by improving food safety or reducing the use of chemical pesticides in agriculture?
Does the technology pose unknown risks for consumers and the environment that will impact on general welfare?
What implications does the technology have for the rights of consumers, for example the right to be informed about the food one is eating?
What implications does it have for the rights of scientists to be free to conduct their research in ways that protect their intellectual integrity?
Who will be the principal beneficiaries from the introduction of the new technologies and what obligations do they have to compensate the losers?
Trying to use guiding principles of this type does not make assessment straightforward. Such principles can’t be applied rigidly in an abstract way as they reflect absolutes such as what is right or wrong. Their operation depends on the context under consideration.
What is precautionary principle?
Current regulation concerning GM crops in the EU is framed to make sure that no harm is done. This is the so-called precautionary principle, which puts the avoidance of harm, to any degree, to the consumer or the environment ahead of any benefits of the implementation of a new technology.
What are the implications of a rigorous implementation of the precautionary principle for the deployment of new technology in agriculture?
Although the precautionary principle provides maximum reassurance of safety, it is unlikely that any fully reliable data set could ever fully quantify the level of risk to human health or to the environment in all possible circumstances. Absolute proof of no risk is not possible. Most technologies have associated elements of uncertainty and if the principle is rigidly adhered to there is the risk that significant benefits are forgone and opportunities to make improvements to food security and safety are lost.
What would be a sensible approach to making an ethical assessment using the principle general welfare with the use of GM crops?
One sensible approach in making an ethical assessment using the principle of general welfare is to try to weigh up the benefits of a technology against its potential to do harm. Deciding whether GM technology is acceptable, in ethical terms, then involves a judgement about the plausibility and moral weight of competing sets of claims. Individuals may make widely different judgements based on the same information, exposing different underlying values and different views on how scientific information ought to be applied. Nevertheless, any judgement should begin with an assessment of the possible benefits and risks.
From your viewpoint, in the response box, list two or three potential benefits of GM crop technology and two or three potential risks.
In terms of benefits, you may have suggested that GM techniques could:
raise agricultural productivity
increase food provision to poorer developing nations
lead to the production of safer, more nutritious foods.
In terms of potential risks, you may have suggested that GM crop technology may:
harm human health
damage the environment, including other organisms
favour the interests of large multinational companies, at the expense of smaller providers.
Considering the second ethical principle that consumers should have freedom of choice what is mandatory when it comes to GM food in the EU?
Considering the second ethical principle – that of the rights of the consumer to have freedom of choice – for many consumers, this is the right to avoid GM food. Labelling of GM food is mandatory in the EU and in quite a few other countries (Figure 3.1). In the USA and Canada this is not the case, despite the demands of popular opinion (Figure 3.2). However, there is a balance to strike here between the choices the consumer demands and the limits that this places on the supplier to comply. This takes the debate into the realms of the third ethical principle – that of justice.
What if labelling was inexpensive, the manufacturer rich, and there was strong public demand for it and yet the likelihood of harm was no greater. Would the argument for labelling be more compelling?
Surely many would argue that a just outcome in this case would be one requiring labelling.
Why would policy makers agree to not put GMO on labeling?
Justice might be considered to involve directing the benefits of a new technology to those who need it most. At the same time, the role of policy-makers is, arguably, to strike a fair balance between the competing rights and welfare of individuals, groups, industry and the state. But achieving justice in this way is again not straightforward. The compulsory labelling of the products of GM crops provides choice to the consumer. But suppose that labelling was very expensive to a relatively poor farmer marketing GM crops, and that the likelihood of harm was generally agreed to be minimal. Many people might take the line that any gains from labelling would be outweighed by the damage to the farmer’s livelihood. Achieving justice in this case might involve taking the side of the farmer.
How does impracticality affect ethical principles? and what are the limits that is allowed of contamination with organic products in the UK and EU?
It is also true that firm ethical principles are of limited value if they are impractical. For example, the segregation of non-GM and GM food is beset with practical problems, and very modest levels of GM contamination are allowed even in food labelled as organic. Organic food is produced under a strict code of practice, which forbids use of most pesticides, herbicides and artificial fertilisers and above all the use of GM crops. European law allows up to 0.9% contamination, while the Soil Association, the body that ratifies organic food in the UK, allows up to 0.1%.
Generally, dissemination of GM technology in low-income countries by not-for-profit research centres and foundations is seen as a good thing. Can you suggest which of the ethical principles this adheres to and why?
The third principle, the principle of justice which suggests that the benefits of the practices are shared by those affected. By removing the effect of large multinational corporations and their requirement to make profits for shareholders, the benefits of the adoption of new technology are more equally shared and the risks of exploitation reduced.
In 2014 how much calories per head did the world produce?
Most people are aware that more equal distribution of existing supplies could resolve food shortages. In 2014 the world produced enough food to supply an average of 2800 kilocalories per head of the global population, exceeding the average daily requirement of 2100 kilocalories. Clearly, the problem is not one of insufficient food but of unequal access to food. Should this point be used to argue against supporting technological progress in food farming in developing nations?
The agricultural yields of which countries/continents are likely to be most seriously affected by climate change and which the least?
How does this compare with the areas of rapid population growth?
Most of the Southern Hemisphere will be adversely affected to some extent: sub-Saharan Africa, India, Pakistan and Bangladesh, most of the Middle East, most of Australia, and most of South and Central America.
Unfortunately, with the exception of Australia, these are the same areas of the world where the population is likely to rise the most.
