Genetic modification of food: yes or no?

What are genetically modified organisms?

A genetically modified organism (GMO) is a micro-organism, plant or animal whose genes have been deliberately altered using genetic engineering techniques.

Genes

A plant or an animal is made up of billions of tiny cells. Each cell contains a nucleus, which in turn contains DNA. DNA is passed from one generation to the next. It holds the information an organism needs to grow, function and reproduce after its kind.

DNA is an information library. A gene is an instruction book within that library. The instructions in genes allow them to make proteins. Proteins are the building blocks of life. An organism is comprised mainly of proteins and molecules made by proteins (e.g. fat, fibre, oil, starch, etc.). Although genes total less than 0.1 percent of the weight of an organism, they control everything else.

Genetic modification

Genetic modification (GM) is the use of modern biotechnology techniques to change the genes of an organism. This can be carried out within the organism (e.g. turning down the activity of certain genes) or between organisms (transgenic genetic engineering) by taking genetic material from one or more organisms and inserting it into another. This creates a plant or animal with completely new properties.

Traditional breeding (aka genetic selection)…

The traditional breeding of plants and animals – or genetic selection – differs from genetic engineering. In genetic selection, half of the genes of an individual come from one parent and half from the other. In genetic engineering, one or more specially selected genes are artificially added to the genome of the plant or animal that is being modified.

Genetic selection is a natural process, designed to enhance certain characteristics in offspring (e.g. resistance to a certain disease, tolerance of specific weather conditions, etc.) by harnessing the genetic resources of that organism. Individuals with favourable traits are crossed with each other over a number of breeding cycles to diminish undesirable attributes and foster desirable ones. The final plant variety or animal breed should hopefully possess the desired traits, along with the associated genes for those traits.

Genetic selection is a vertical process: it can only occur between closely related forms of life (i.e. dogs with dogs, not dogs with ducks; apples with apples, not apples with aardvarks; etc.).

…versus genetic modification (GM)

Although proponents of genetic engineering sometimes equate GM with genetic selection, genetic modification changes an organism’s genes in ways that are not possible via traditional breeding. In transgenic GM, artificial gene units are created in a laboratory, then inserted into the target plant or animal to re-programme its DNA with completely new properties.

GM is a horizontal process: genetic material from one species is inserted into an unrelated species, a process that does not happen in traditional breeding because the organisms are not genetically compatible. Transferred genes are called ‘transgenes’. They can come from another plant or animal species, or from bacterial or viral genes.

The genetic engineering of plants, for example, often uses a bacterium with a natural ability to transfer DNA to certain flora. When the bacterium infects the plant, it penetrates the plant’s cells and transfers its modified DNA to that plant. Transgenic DNA can also be introduced physically by shooting it into the plant nucleus with a ‘gene gun’. Once in the cell nucleus, it inserts itself at random into one of the host chromosomes and can express the desired characteristic. The GM plant is then grown from the altered cell.

Most GMOs contain patented transgenic genes from viruses and bacteria plus DNA from a plant and/or an animal (e.g. tomatoes with fish genes, potatoes with spider genes, pigs and rice with human genes, etc.). The GM gene in the most common herbicide-resistant soya bean variety, for example, contains genetic material from a plant virus, a soil bacterium and a petunia plant.

GM-gene escape (or horizontal gene transfer in the environment)

A very serious – and heretofore underestimated – consequence of horizontal gene transfer is so-called GM-gene ‘escape’. The ‘escape’ referred to is horizontal gene transfer in the open – the spread of GM genes by infection and multiplication (much like a virus), regardless of species barriers; the rate of spread is thus much faster and the extent of it virtually unlimited. At issue is what the consequences could be. New combinations of genetic material, created at unprecedented speed, affect fast-reproducing species the most, i.e. bacteria and viruses, which potentially cause disease.

Horizontal gene transfer and recombination is a major route for generating new strains of bacteria and viruses that cause illness. Genetic modification and the release of GMOs into the environment has created highways for horizontal gene transfer and recombination where previously only the occasional laneway existed. Concerned scientists have long considered horizontal gene transfer to be the most grave hidden and underestimated danger of genetic engineering and have alerted regulators to it time and again since GMOs were released. Please read this report for further information.

Controversy

Genetically modified organisms to date include patented viruses, bacteria, algae, fungi, seeds, crops, trees, insects, fish, crustaceans, poultry and livestock that have been infected in a laboratory with foreign DNA from viruses, bacteria, plants and/or animals.

Currently, much of the controversy regarding genetic modification centres on GM crops, such as soya, maize, cotton, oilseed rape (Canola) and others.

According to GreenFacts, ‘a number of economically valuable characteristics have been introduced into plants by genetic engineering. Most of the genetically modified crop plants used so far have transgenes that provide resistance to herbicides or insects. To improve crop production and soil management, research is now exploring how to increase the variety of transgenic characteristics to include resistance to drought, heat, cold, acid soils, and heavy metals. These characteristics will increase the range of soils and climates that are able to support agriculture.’

GM Watch, however, cites two papers that raise serious concerns about the genetic stability and safety of GM plants: ‘The GM transformation process of plants is crude, imprecise, and causes widespread mutations, resulting in major changes to the plant’s DNA blueprint.1 These mutations unnaturally alter the genes’ functioning in unpredictable and potentially harmful ways… 2 Adverse effects include poorer crop performance, toxic effects, allergic reactions, and damage to the environment.’

Common arguments

Proponents of genetic modification claim that GM crops:

  • are safe to eat and more nutritious
  • benefit the environment
  • reduce the use of herbicides and insecticides (either because the plant is bred to be resistant to certain proprietary weed killers or because it is bred to produce an intrinsic insecticide)
  • increase crop yields, thereby helping farmers and providing a solution to the world food crisis
  • create a wealthier and more stable economy
  • are just an extension of traditional breeding (genetic selection) and carry risks no different from naturally bred crops

However, a large and growing body of scientific research and direct farming experience indicate that GMOs are failing to live up to these claims. Instead, GM crops:

  • can be toxic, allergenic, or less nutritious than their natural counterparts
  • can disrupt the ecosystem, damaging vulnerable wild plant and animal populations and harming biodiversity
  • increase chemical use (pesticides and herbicides) over the long term as weeds and insects develop resistance to chemicals
  • deliver yields that are no better – and often worse – than conventional crops
  • cause or exacerbate a range of social and economic problems
  • are made in the laboratory and, once released, cannot be recalled from the environment – particularly problematic if the GMO proves to be harmful in its effects

For a detailed but clear and well-referenced discussion of these points, including how organic and low-input farming methods – rather than GM – genuinely improve yields, food security and farmer incomes in developing countries, please see GM Crops: Just the science.

Contamination

Although GMOs are novel organisms, untested by evolution, they can replicate and be inherited. Plants containing transgenes have been known to breed with conventionally and organically grown crops. As a GMO gene is a dominant gene, it will render any seeds or plants it contaminates genetically modified.

This suggests that co-existence between GM and conventionally/organically grown crops is not viable if non-GMO plants are to remain GMO-free, as per the wishes of their growers and buyers. Once GMOs are released into the environment, it is impossible to control the pollen drift, weather patterns and human, insect and animal activity that spread them far and wide, and they cannot be recalled.

Quite apart from experimental GM plants, such as pharma crops, traitor crops and terminator crops, genetic modification is itself a giant experiment. The function of genomes is still only partially understood, yet foreign genes are introduced into crops with no precise knowledge of what is going to transpire when the plant is grown and used or consumed. The long-term health and environmental impacts of GMOs are scientifically impossible to predict.

Contamination incidents in 39 countries have proven that GMO crops can infect related species, unrelated species, agricultural seed supplies and the human food chain (please see the GM Contamination Register).

Patents

Ninety percent of GM crops belong to the corporate agriculture group Monsanto. The rest are owned by Syngenta, DuPont, Bayer and others. Farmers who have gone the GM route, believing promises of better yields, have instead experienced yields no higher than normal crops, plus mounting costs for annual supplies of patented genetically engineered seeds and proprietary herbicides. After a while, some weeds become resistant to herbicides, and pests to pesticides, meaning that more has to be used to keep them at bay, resulting in damage to non-target wildlife, soil and groundwater. Please see this short video for more information (once you reach the page, scroll down): Genetic engineering: The world’s greatest scam?

Biotech corporations have also sued conventional and organic farmers for allegedly growing GM crops without a licence, even though the farmers insisted their crops were contaminated by GMOs against their will. Many farmers have lost their entire livelihoods (including non-GMO contaminated seeds and crops) to biotech corporations, thanks to the enforcement of complex trade-related intellectual property laws (TRIPS). The case of Canadian farmer Percy Schmeiser and Monsanto covers many issues relating to biotech corporations, patents, and corporate efforts to dominate seed supply.

Politics: GM and Ireland

Thanks to a loophole in the law, genetically modified animal feed can enter the food chain unlabelled. This is particularly insidious, given that the majority of European citizens have consistently stated that they would not eat GM-labelled food by choice.

According to GM-Free Ireland, most Irish beef, lamb, pork and dairy produce is made from livestock fed on imported genetically modified feed, especially GM soya, in spite of the growing rejection of GMOs by leading European food brands and retailers. The only way to be sure of avoiding GM-fed animal products is to buy organically raised flesh foods and dairy produce.

Latest news

22 March 2011

Welsh scientist and anti-GM campaigner Dr Brian John of GM-free Cymru has persuaded the EU Parliament to call for an investigation into the alleged industry bias of the European Food Safety Authority (EFSA) on GMOs: Anti-GM scientist wins probe into food safety by Steve Dube

References

1.The Mutational Consequences of Plant Transformation. Latham J.R. et al. J Biomed Biotech. 2006, Article ID 25376, 1-7, 2006.
2.Transformation-induced mutations in transgenic plants: Analysis and biosafety implications. Wilson A.K. et al. Biotechnol Genet Eng Rev., 23: 209-234, 2006.

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