Genetically Modified Organisms: Why All The Controversy? GMOs can generate substantial benefits for producers and consumers, but resistance to GMOs is likely to continue until questions are resolved concerning their safety for people, animals, and the environment. by Matthew P. Feldmann, Michael L. Morris and David Hoisington

"'\VJhy have genetically modified organ­ 1. What is a GMO? the gene responsible for tbe desired trait. W isms (GMOs) suddenly become a GMOs are living organisms (plants, ani­ After the gene has been identified and iso­ lighming rod for public debate? Proponents mals, bacteria) into which foreign genes lated, it is in serted into the cell of another of GMOs say that genetic modification of have been inserted. The foreign genes come organism using one of several techniques. plants and animals is nothing more than from various so urces and change the cha~­ The most widely known technique involves the latest in a long series of productivity­ acteristics of the recipient organism. Genet­ a "gene gun," a device that uses bursts of enhancing technologies that have helped ically modified crops, the focus of this arti­ helium to propel microscopic particles, increase the world's food supply. Oppo­ cle, are designed to do one of two things: coated with copies of the gene, directly into nents counter that GMOs are fundamentally (1) lower farm-level production costs, or the receptor cell. A second co mmon tech­ different from naturally occurring organ­ (2) enhance product quality. nique uses a bacterium to invade the recep­ isms - so different that they pose a threat tor cell and "pl ant" some of its DNA along to the character and quali ty of the food sup­ 2. How are GMOs produced? with the foreign gene that carries the desired ply. Who is right? We attempt to shed light GMOs are produced through genetic trait. In either method, the foreign gene is on the controversy by addressing 10 basic engineering, a process in which genes that not inserted into every potential receptor questions about GMOs. yield desirabl e traits are transferred from cell, so it is necessary to identify cells that one organism to another. Genetic engi­ have been successfully modified. This is neering begins with the identification of done by inducing the receptor cells to

8 CHOICES First Quarter 2000 develop into mature plants, which are then scree ned to determine whether the foreign ge ne is pres­ ent and functioning properly. Plants that have been successfully modified display the desired trai t.

3. Why are GMOs so controversial? Genetic engi n'eering diffe rs fro m conve ntional plant and ani­ mal breeding because it all ows ge nes to be moved across taxo­ nomic boundari es . W ith genetic engineering, genes can be trans­ ferred not only between cl osely related organisms (as from a wheat plan t to a ri ce plan t), but also between entirely different organ­ isms (perhaps from a fis h to a strawberry plant). In conventional breeding, nature imposes limits on genetic recombination by erecting barriers against crossing between biologically di stin ct organisms. With genetic engineering, these barriers do 6. What are the potential benefits Same plant, new not always have to be respected, which is why some peo­ of GMOs? t raits. Changing the ple consider GMOs to be "unnatural organisms" that Most transgenic crops currently being grown feature ge net ic makeup of an violate the laws of nature and are likely to be dangerous. trai ts designed to increase farm-level productivity by rais- o rganism requires the ing crop yields and reducing input use. Probably the bes t- desired gene to 4. Who produces GMOs? known example invo lves Bt, a ge ne from the so il -born e inserted eithe r by Most research on Q'ansgenics (another term for GMOs) bacterium Bacillus thuringiensis that induces plants to bacterium "planti ng" is carried out in industrialized countries, where the lead­ produce a pro tein that is toxic to insect pes ts. T he resis t- or by "ge ne gun" ing life-science companies that dominate the global seed ance co nferred by Bt can increase yields and reduce the t echnology. in dustry are investing heavil y in genetic engineering of need fo r chemical pes t control. Based on trials conducted Photo courtesy of the authors. crops. T he large m ul tinationals represent only the tip of in the United States, Koziel, et al. , es timate yield gains of the industry iceberg, however, as they are supported by up. to 8 percent in Btcorn . Reduced use of pes ticides fur- hundreds of smaller research fi rms, speciali zed equip­ ther increases profi ts, saving an average of $2.80 to $14.50 ment manufacturers, and universiry laboratori es. per acre in the United States (Carlson, Marra, H ubbell). Another input-reducing transgenic technology involves 5. Where are GMOs currently a ge ne th at co nfers res istance to glyphosate herbicides. being grown? Monsanto used this gene to develo p glyphosate- resistant Research on ge neti cally modified crops began decades varieti es of co tton, soybeans, and co rn, which are so ld ago, but only recently have products been available for com­ under the brand name Roundup ReadyTM. O ne ap pli­ mercial use. In 1990, China became the first co untry to ca tion of Roundup TM herbicide is usually sufficient to introduce a genetically modified crop, a virus-resistant achieve effective co ntrol of broadleaf weeds. Data fro m to bacco va ri ety. In 1994, a del ayed-ripening tomato became the first geneti cally modified foo d crop to be grown commercially in the United States . Since then, genetically modified crops have fo und their way into The worm has far mers' fi elds with increasing frequency. By 1999, .trans­ turned . GMO t raits ge ni c crops covered nearly 100 million acres in the United ca n ta rg et specific pests States, Argentina, Canada, China, Australia, South Africa, t hat are difficult to Mexico, Spain, France, Portugal, Romania, and Ukraine co ntro l.

(James). Photo courtesy of the authors.

First Quarter 2000 CHOICES 9 the U nited States suggest that Roundup Ready soybeans resistance. To date, no evidence has emerged to show increase farmers' profits by an average of $5.65 per acre that consumption of geneticall y modified feeds has (Carl son, Marra, Hubbell). affected animal health, although few long-term feeding Unlike the first-generation transgenic crops that were trials have been carri ed out. designed to lower production costs, seco nd-generation Environmental impacts transgenics will feature enhanced nutritional qualities. Probably the most controversial set of iss ues sur­ Plant breeders have tried for decades to develop crop vari­ rounding GMOs relates to their possible long-term eties with added vitamins and minerals. Recent advances impacts on the environment. Any crop (transgenic or in genetic engineering methods should all ow rapid not) that has been bred to resist pests or diseases carries progress in this area. N utritionally fortified crops should the risk that the targeted pests or diseases may themselves prove especially valuable in developing countries, where develop resistance to the crop's defense mechanisms. Some millions of people suffer from chronic dietary deficien­ scientists believe that insect resistance to Bt-produced cies. They should also be attractive in industrialized coun­ toxins will emerge fairly quickly, since insects will be con­ tries as a means of reducing consumption of unhealthy oils, tinuously exposed. The recent discovery that several insect proteins, and starches. species have developed resistance to Bt (as a result of exposure to Bt sprays, not to transgenic Bt crops) has 7. What are the potential risks raised renewed questions about the longevity of the resist­ associated with GMOs? ance. Human and animal health Another risk linked to the potential emergence of No evidence shows that genetically modified foods resistance in insects is that Bt might lose its effectiveness are injurious to humans. Even so, there are lingering fears as a topical pesticide. Bt-based sp rays and powders are that consuming GMOs might lead to an increase in dis­ used to control pests in a number of fruit and vegetable eases that are r~sistant to several antibiotics. This con- crops. Since Bt occurs naturally, these pesticides are espe­ cially popular among organic farmers. If the widespread planting of transgenic Bt crops fosters the emergence of As with any new product, Bt-resistant insects, farmers who currently rely on Bt­ it is important that the based topical pesticides could suffer im portan t losses. While some worry that genetically engineered Bt crops potential risks be evaluated may not be effective enough, others worry that they wi ll before any GMO is approved be toO effective by killing insects orner than the targeted pests. The highly publicized Cornell University monarch for commercial use. butterfly study, which showed a heightened mortality rate among monarch larvae fed on transgenic Bt corn pollen, raised the possibility that non-pest insects could cern developed when some genetically modified crops be harmed (Losey, Rayor, Carter). After the Cornell study were found to contain antibiotic resistance genes left over was published, researchers at Iowa State University cau­ as residue from the bioengineering process. Even though tioned against extrapolating ftom findings obtained under the antibiotic resistance genes are not active, health spe­ laboratolY conditions to the actual conditions faced by wild cialists worried that, if present in sufficiently large num­ monarchs (Rice). bers, they could accumulate in rhe bodies of consumers. Environmental concerns have also been raised about This concern has recently been allayed, as researchers transgenic herbicide resistance. Herbicide-resistant genes have devised gene-transfer techniques that avoid the use could conceivably jump from genetically modified crops of the antibiotic resistance genes. to other wild or domesticated species, producing "super Another potential risk posed by GMOs is that people weeds" that resist conventional control methods. In order with allergies could suffer reactions after unwittingly con­ to control these super weeds, farmers might have to switch suming modified food co ntaining allergenic substances to more powerful herbicides. Studies are underway to introduced from external so urces. Proponents ofGMOs evaluate the potential environmental co nsequences that argue that sin ce very few genes produce harmful com­ might ensue should herbicide-resistan t genes acciden­ pounds, the likelihood of this happening is extremely tally spread from domesticated crops. low. And even if an inserted gene were to result in pro­ duction of a harmful compound, the chances of it reach­ 8. Why do consumer attitudes about ing consumers are negligible, because it would be found GMOs differ so much around the by food safety inspection and testing. world? GMOs are also feared by some li vestock producers Consumers have diverse attitudes about GMOs - who worry that until the use of antibiotic resistance genes especially genetically rl10 difled food. The Arlan tic Ocean is completely discontinued, animals fed on genetically apparently represents a major fa ult line in public senti­ modified grain co uld experience a buildup of antibiotic ment: GMOs seem to have been tacitly accepted in the

10 CHOICES First Quarter 2000 Food f or t hought . In developing countries - where millions go to bed hungry and where food prices directly affect a large propor­ tion of the the popula­ tion - GMO potential to feed and pay many people cannot be ignored.

Photo courtesy of the authors.

United States, whereas they have inspired wides pread protect them from unsafe foods, but European regula­ protest in Europe. T he differences in attitudes appear to tory agencies are viewed with suspicion (Gaskell, Bauer, be due to two main factors. Durant, Allum). The skepticism in Europe stems from First, public awareness of the prevalence of geneti­ recent incidents in which regul atory agencies initially cally modified foo d varies greatly. European retailers are failed to detect the seriousness of food safery problems and required to label products co ntaining GMOs. This then tried to downplay their likely consequences. requirement has helped alert co nsumers to the prolifer­ ation of genetically modified food. American retailers do 9: Are GMOs appropriate for not face this requirement and have fought hard to pre­ developing countries? vent labeling. As a result, most American consumers are Although the debate over GMOs is taking place mainly not aware that many of the products they consume con­ in the United States and Europe, developing co w1rries tain genetically modified ingredients. T his lack of aware­ have an important stake in the outcome (Nuffield Coun­ ness has w1questionably co ntributed to the relative com­ cil on Bioethics). Many developing countries still depend placency of American co nsumers. heavily on agriculture and stand to benefi t dispro por- tionately from any technology that can increase fo od production, lower In places where there is not enough food food prices, and improve food qual­ to go around and where food prices ity. Prince Charles may be correct when he says that GMOs are unnec­ directly affect the incomes of a large essary in Britain, where the cost of proportion of the population, the potential raw commodities makes up a small fraction of the final price paid by productivity gains offered by GMOs cannot consumers for h eavily processed, easily be ignored. elaborately packaged, and extensively adve rtised food. It is hard to make the same argument in developing Second, consumers on either side of the Atlantic dif­ co untries where millions go to bed hungry because food fer in their trust of food safery regulation sys tems. Amer­ is unavailable or unaffo rdable. In places where there is ica ns in ge neral have faith in the government's abi liry to not enough fo od to go aro und and where food prices

Fi rst Quarter 2000 ' CHOICES 11 ognize the validity of others' concerns and take steps to resolve unanswered questions. Finally, decisions abour me future ofGMOs should be based on facts, nor unsubsranriated claims or half-rruths. Many of those engaged in the debate over GMOs use information selectively, glossing over gaps in the knowl­ edge base or bolsrering their arguments with misinfor­ mation. If the concerns that have been raised are to be resolved, politically motivated rhetoric must give way to serious discussion based on credible, science-based infor­ mation. T he srakes are roo high ro waste more time on use­ less posruring .•

A more comprehensive version ofthis article can be found at the CIMMYT website. Point your Internet browser to http://www.cimmyt.cgiar.org then link to "Research Pro­ grams, " then to "Applied Biotechnology Center. " "WC would like to be genetically modified to taste like Brussels sprouts. » • For More Information Carlson, G.A., M.C Mara, and B. Hubbell. "The Eco­ Everything but the directly affect me incomes of a large proportion of the pop­ nomics of First Crop Biorechnologies." North Carolina "moo." Consumer­ ulation, me potential productivity gains offered by GMOs State University, Raleigh, 1997. oriented messages cannot easily be ignored. use the "genetically Gaskell, G., M.W. Bauer,]. Durant, and N.C Allum. modified" terminol­ 10. What are the long-term prospects "Worlds Apart? The Receprion of Genetically Modified ogy but often skirt for GMOs? Foods in Europe and rhe U.S." Science, vol. 285 , no. around the real Despite the current uncertainty over the future of 5426. Washington, DC: American Associarion for the debate over biotech­ GMOs, several mings are clear. Advancement of Science, 1999. nolgy. First, genetic engineering is toO important to ignore.

C The New Yorker Collection 2000 Given recent advances in biotechnology, the process by James, C 1999. "Preview: Global Review of Commer­ Sam Gross from cartoonbank.com. which humans breed better crop varieties has changed All rights reserved. ciali zed Transgenic Crops: 1999." ISAAA Briefs No. 12. forever. Although it may not always be possible to iden­ Irhaca, NY: International Service for me Acquisition of tify genes of interest and move mem around at will, in cases where economically valuable genes can be identified and Agri-biotech Applicarions, 1999. manipulated, using conventional breeding methods may be inefficient. Koziel, M. G.; G.L. Beland; C Bowman; N.B. Carozzi; Second, the possi bility of making gene transfers R. Crenshaw; L. Crossland; ]. Dawson; N. Desai; M. between and among completely different species of plants, Hill; S. Kadwell; K. Launis; K. Lewis; D. Maddox; K. animals, and bacteria opens the door to crearing organ­ McPherson; M.R. Meghji; E. Merlin; R. Rhodes; G.W. isms mar differ from rhose that occur naturally. Whemer Warren; M. Wright; S.V Evola. "Field performance of the differences are differences in kind or merely in degree elire transgenic maize plants expressing an insecticidal does not really matter. As wirh any new producr, the prorein derived from Bacillus rhuringiensis. " BiolTech­ impacts of GMOs on people, animals, and the environ­ nology4 (11 )(1993): 194-200. ment are difficulr to predict, so it is important that the potential risks be evaluated before any GMO is approved Losey, ]. E., L.S. Rayor, and M.E. Carter. "Transgenic for commercial use. pollen harms monarch larvae." Nature, vol. 399, no. 6733 Third, given the importance of food, policies regard­ (1999). London, UK: Macmillan Magazines Ltd. ing GMOs must be based on an open and honest public debate. In hindsight, it is clear that the agri-biorech indus­ N uffield Council on Bioethics. "Genetically Modified try miscalculared by arguing that genetically modified Crops: The Ethical and Social Iss ues." London: Nuffield foods are no different' from other foods. This attitude Council on Bioethics, 1999. served to heighten suspicions that the industry is seeking to increase profits by promoting a technology that has Rice, M. "Monarchs and Bt Corn: Questions and few benefits and may pose some dangers. In order to Answers." Integrated Crop Management. Department move forward, all parties in the debate will have to rec- of Entomology,.I. ow a State Un iversity, Ames, Iowa, 1999.

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