1! Farmers have been genetically modifying plants for 1000s of years Artificial selection propagates bad traits with the good Most recently, trying to eliminate bad traits! Modern technology allows for the insertion of desirable genes into target organism genomes (recombinant DNA) 2! 1) Agriculture A) resistance/tolerance to insects B) resistance/tolerance to herbicides C) resistance/tolerance to pathogens! 2) Public Health Production of vaccines (ex. insulin) or protein products (ex. Growth hormones)! 3) Forestry Production of tree varieties resistant/tolerant to pathogens or of increased quality (ex. Lignin production, pollution tolerance)! 4) Other Industrial biomaterials, environmental rehabilitation organisms 3 1
! First products: bacterial gene insertions to create human protein products Insulin Growth hormones No societal resistance whatsoever! First products intended for human consumption: Plants resistant to pesticides GMO tobacco in field studies from 1986-1989 4! Why resistance against pesticides?! Traits associated with yield (seed quality, early maturation, nitrogen fixation etc.) are often multi-gene complexes, therefore molecular techniques are too complicated! Traits for resistance are often associated with only one gene in particular 5! Nutraceuticals Medicinal properties Added value! Transgenic animals Milk with added nutrition/medicines Less susceptible to disease Limit pollution from manure! Plants tolerant to wider range of conditions Dessication, salt, better PS 6 2
! Increase yield/decrease losses! Decrease external costs! Increase value of crops! Reduce environmental damage! Improve quality of life by eliminating deleterious genes (ageing, cancers etc.) 7! 1) Subjective Ethical, political, theistic, social, economic! 2) Rational/scientific A) poses no danger upon consumption Ex. Human or animal food B) poses no danger to the environment Ex. Perturb ecological processes Ex. Resistance 8! Much confusion, ignorance and disinformation exists! Most people lack the basic understanding required to discuss the topic Ex. a UK poll demonstrated that 60% of respondents did not realize that non-gmo tomatoes also contained genes! Other problem: there is no consensus on the definition of a GMO 9 3
! 1) over the process Unnatural, playing God Due to molecular homology we already share most of our genes across very distant taxa what s one more? Pork gene in a tomato Can it be eaten by jews/muslim? What if the gene already exists in tomatoes? For non-food GMOs (insulin or cystic fibrosis enzyme from bacterial gene insertion and cloning) Most people are ok with this form of GMOs so they are not inherently against the process itself! 2) over the products (potential) Creating monsters Haven t yet seen any problems 10! Genetic modification = genetic engineering = recombinant DNA (rdna) A series of technologies and processes Ex. Molecular analysis, gene identification, gene extraction and cloning, gene splicing and gene transfer Most people consider only the latter to be GM We end up by creating an organism with novel traits (Canada s regulation applies at that level) 11! In Canada, a GMO: All organisms with traits that do not exist in the natural varieties (organism with novel traits) This applies to organisms created by traditional methods of selection Most of our food (microbes, plants, animals) are currently genetically different from their natural cousins 12 4
! As a function of their inherent properties Ex. Canada Control is based on the product, not the process! As a function of their mode of production Ex. USA! As something completely different Ex. EU 13! Selection! Crossings! Emasculation Prevent paternity in non-desirable plants! Genus crossings Ex. Triticale: wheat and rye! Haploid selection Forcing double haploid embryos to develop 14! Mutant selection Expose plants to mutagens to see what is created >1400 cultivars from several spp.! Somaclonal variation Provoke genetic changes during micropropagation in cultures! Cell selection Growth of cultured cells and mutants are selected for propagation Selection for resistance is based on applying noxious chemicals or poisons to remove normal cells 15 5
! Risk: probability that something poses a danger! To public health: Increase in toxicity, allergens or decrease in nutritional quality Risk for toxicological profile is calculated using a) biological activity of the product, b) the frequency, intensity and duration of exposure 16! 1) Modification of the rhizosphere by gene transfer 17! 2) Diffusion of GMOs into the environment Super-Weeds could become invasive In W Canada, natural populations of Canola have become resistant to herbicides Margin of security: artificial selection has weakened hardiness of agricultural crops Herbicide resistance not really an issue in nature, other forms of tolerance could be problematic 18 6
! 2) Diffusion of GMOs into the environment Gene flow between GMO populations and natives 12/13 of the most important plant crops are grown in proximity of their wild cousins (ex. wheat, rice, corn, soya, cotton, barley) How to control? Dispersal by pollinators, seeds 19! 2) Diffusion of GMOs into the environment Ex: Starlink Corn (B.t.) Protein product Cry9C (similar to many allergens) Banned from human consumption Approved pour industrial nonfood uses, animal feed and the production of grain Contamination has been documented in food products (requires recalls, inquiries, compensations etc.) 20! 3) Risks of insects developing resistance to GMOs Many species already show B.t. resistance in laboratory One case observed in nature: Diamond-backed moth (Plutella xylostella) on crucifers in FLA and NY! Selection pressures are more intense because expression is continuous in GMOs 21 7
! Strategies to reduce the potential for resistance Mixed cultures Non-GMO refugia around GMO crops EPA (2000): no more than 80% of a crop can be GMO B.t. 22! 4) Negative effects on biodiversity Agriculture is already among the human activities that leads to biodiversity losses UNEP: biodiversity loss has been accelerating since 1600, has reached 100x the natural rate A) genetic homogenization of parental stocks B) effects on non-target organisms and up the food chain 23! Pleiotropic effects Genes rarely act in isolation Many interactions exist between genes and the genome Ex. Regulators of the expression of other genes (amplitude) Ex. Initiators or terminators of the expression of other genes 24 8
! Reduction of pesticide use Australia: noticed a reduction of 50% in 2 years with B.t. cotton USA (1998-1999): reduction of 21% with B.t. cotton USA: reduction of 10-30% with GMO soya USA in general (FDA): pesticides were reduced in 7/12 regions, but not in the other 5/12 25! Why no reduction in 5/12 regions? Herbicide resistant GMOs created to be specifically used with a particular pesticide Ex. Monsanto Round-up Ready plants can only be used with glyphosate 26 Target Species Source: G Frisvold, University of Arizona 27 9
! Proposed at the Rio Earth Summit in 1992! Signed at the UN conference on the Environment and Sustainable Development! if an action or policy has suspected risk of causing harm to the public or to the environment, in the absence of a scientific consensus that harm would not ensue, the burden of proof falls on those who would advocate taking the action. 28! UN convention on biological diversity in Montréal in 1993! Strategies aimed a maintaining biological species and ecosystem diversity! Addition to the PP in order to include the risks associated with biotechnologies (GMOs)! PP and CP: international guidelines for the evaluation and standardization of food products 29! GMO creation is under rigorous and elaborate scrutiny at every step Many more varieties are created by genetic engineering than by conventional methods We have no idea what genes are created by mutation but we know exactly with gene transfer 30 10
! Different processes are often confused with one another Ex. Herbicide-resistant Canola coming from Canada (GMO) are banned in the UK, but not those coming from Australia (conventional) Ex. Whole organisms and derived products are often considered as equivalent - tomatoes (intact DNA) vs. paste (denatured DNA) Some refined products contain no genes or protein products (oils, sugars etc.) 31! Have been growing experimentally for 35-40 years Thousands of generations of GMO plants! GMO products have been consumed by humans since 1994! No pronounced effect has been observed in public health or on ecosystem functioning to date! When unintended effects have been discovered, those strains have been scrapped Ex. Beans with nut gene 32! GMO plants must be exactly the same as cousin plant, except for GM! Must be considered Substantially Equivalent Agricultural, environmental and public health parameters 33 11
GMO plants World cultivated surface (M ha) % of all GMOs % of this plant s production globally Soya 25,8 58,4 36 Corn 10,3 23,3 16 Cotton 5,3 12 11 Canola 2,8 6 7 Total 44,2 99,7 16 34 35 USA Canada UK Corn 12 15 1 Canola 7 15 5 Tomatoes 6 3 4 Cotton 5 5 0 Potatoes 4 4 0 Soya 3 1 1 Beets 2 0 0 Gourds 2 2 0 Radishes 1 0 0 Papaya 1 0 0 Linseed 1 1 0 Total 44 42 19 36 12
Country 1999 2000 % change USA 28,7 30,3 +5,6 Argentina 6,7 10,0 +49,3 Canada 4,0 3,0-25,0 China 0,3 0,5 +66,7 S Africa 0,1 0,1 +100 Australia 0,1 0,2 +100 Other <0,1 <0,1 - Total 39,9 44,2 +10,8 37 Canada Ontario Quebec Wheat 20 695,3 1 222 116,9 Corn 7 550 4 750 2 800 Barley 11 103,3 387,5 485 Oats 2 838,3 74 210 Rye 201,5 54,6 3,2 Soya 2 040,1 1 660,1 380 Canola 4 788,8 31,3 10 Mixed Cereals 375,8 208,7 3,2 38 Sales R&D Syngenta (Swiss) 5 888 745 Monsanto (USA) 3 885 588 Aventis (France) 3 701 469 DuPont (USA) 2 511 1776 Dow (USA) 2 271 892 Bayer (Germany) 2 252 2208 BASF (Germany) 2 228 758 39 13
! Gouvernement du Québec. Conseil de la science et de la technologie. 2002. OGM et alimentation humaine: impactes et enjeux pour le Québec. 178p.! McHughen, A. 2000. Pandora s picnic basket. Oxford University Press, NY. 277p. 40 14