by Lisa J Daniel

Lisa Daniel is a doctoral scholar supported by the Rural Industries R&D Corporation. After 8 years working with biotechnology in scientific research, she is currently researching the integration of biotechnology into industry through the Graduate School of Management at the University of Queensland. Lisa is the principal of Chrysalid Consulting, and the founder of BiotechWeb, an information platform on biotechnology. BiotechWeb welcomes questions, information and dialogue: info@biotechweb.net.au

Just as J.R.R.Tolkien’s Middle Earth was full of strange, wondrous and frightening things, so too is the world of biotechnology. Turning science on its head and forever ensuring biological understandings of micro-proportions (pun intended), biotechnology has created chasms in opinion of paradoxical proportions [1]. The most emotive of these come from the debate about genetically modified (GM) food. Attempting to find middle ground in the information on genetically modified food requires careful searching and a rational approach into swamps of steamy emotions, wild fears and corporate barracudas. The first step requires coming to terms with the science of biotechnology.

History

Biotechnology is just a new word for an old science. Humans have long recognized that biological organisms have a plasticity that enables change. This adaptability has contributed to the opportunities for improved survival. Humans have intentionally and unintentionally cultivated this characteristic. Brewing, baking, wine making, and plant and animal farming have relied upon selection and breeding of effective organisms for quality improvement and production increases. Biotechnology continues this tradition but through sophisticated molecular techniques. Biotechnology can be defined as the manipulation of biological organisms or parts thereof, at the cellular, sub-cellular or genetic level with the intention of producing unique changes for specific applications. Using biotechnology an organism’s characteristics are adapted, as its DNA is changed through genetic engineering, to produce an altered organism or a biological tool . (Altered organisms include microorganisms used in beer fermentation, cheese production and as biological factories for specific enzyme or hormone production. Biological tools include drugs developed from genetically engineered organisms - e.g. insulin, genetic probes for identification - e.g. in forensics, resistance triggers in plants e.g. Bt corn.)

Rosalind Franklin (1920-1957) first elucidated the structure of DNA in 1952 using x-ray diffraction crystallography. She identified that the negatively charged phosphates would push the sugar-phosphate back-bone to the outside of the molecule. This provided Watson and Crick with the evidence for their cardboard cut-out experiment that allowed them to determine that the DNA structure spiraled into a double helix (Watson & Crick didn’t conduct their own laboratory experiments but talked to other researchers and built chemical models. The historic model of DNA was first constructed with cardboard. [2]). Rosalind Franklin was not included in the publication that reported the structure of DNA.

Once the structure of DNA had been discovered it was still another two decades until scientists were able to strategically manipulate the molecule. Biotechnology had its contemporary beginnings with the success of two fundamental technologies; gene fusion with recombinant DNA (1973) and hybridoma technology i.e. cell fusion in 1975. Taken together with Mendel’s studies on heredity, biotechnology and genetic engineering have taken leaps forward. Applications in biological processes and product development include developments in medicine, agriculture, industrial chemicals and processes, and food production. Of all these current applications the debate over GM food is the most emotive.

GM Foods and the Consumer

Food is comfort. From the beginning this is what we know. Consumer and environmental concerns are undoubtedly the source of much of the angst in the GM food debate.

Potential for Transfer of Genes from GM Food

Genetic modification of food crops requires the introduction of a selected gene (to deliver the desired improved characteristic), together with a marker gene. Marker genes are often antibiotic or herbicide resistance genes that allow selection of plants that have successfully integrated the gene of choice. A popular topic in the debate is the use of antibiotic resistant genes in the production of genetically engineered crops.

There are fears concerning the possibility of transfer of the resistance characteristic. Such a transfer could potentially occur at a number of levels, such as into the surrounding environment, or into gut flora or across to our own cells in the gut lining. For such events to be possible a long and complex chain of events would be required. These include the replacement of the plant promoter (on/off switch) on the transgene (transferred gene) with a suitable host-specific alternative, availability of host cells competent for transformation (able to take up external DNA) and an environment conducive to the intact transfer of the naked gene segment into recipient cells. A variety of antibiotic resistance is naturally found in most bacteria, many of which are frequently present in foods that we regularly consume [3]. The chance of antibiotic resistance transferring from a GM crop to a human pathogen appears to be infinitesimally small [4]. The chance of the marker remaining intact following ingestion, to be taken up by gut bacteria then integrated and expressed would similarly be miraculous.

The possibility of transfer of transgenic DNA across the gut and insertion into the human genome has been debated. Schubbert et al [5] were able to show in mice that the intestinal tract is not an impermeable barrier to foreign DNA, however integration of transgenic (or other) DNA into the genome with requisite promoter for functional transcription has not been demonstrated. The fact is that we eat millions of genes every day; many that we have not been exposed to before. Such new genes include those produced in new plant varieties through conventional selective breeding programs [6].

Levels of Genetic Modification

There are varying levels of genetic modification associated with the food production process. We can consider these at three levels; 1) production, 2) manufacture and 3) principle applications.

Production application can be considered to be the least direct involvement, utilising GM food products as ingredients in the production of the final food item e.g. GM corn starch in sauce. Manufacture applications would be closer to the final product and uses GM components or processes (such as fermentation) in the manufacture of the food item e.g. the genetically engineered enzyme ‘chymosin’ used in cheese making. This genetically engineered enzyme has replaced the natural product (traditionally extracted from calves stomachs). Finally, the modification as principle application in foods would be as part of the final product eg. GM fruit and vegetables.

There is no doubt that the potential benefits of GM foods are profound. The opportunity to complement an inadequate diet with nutritionally improved food products offers health benefits in developed countries as well as subsistence economies.

The numerous studies of transgenic organisms and food products undertaken prior to commercial marketing in many countries (e.g. the EU, US, UK, Japan, Canada and Australia) have revealed there is no substantial evidence to suggest that approved GM foods are any more dangerous than conventional foods [7, 8, 9]. In fact they are so well scrutinized they are probably safer!

While it is commonly acknowledged that with proper distribution the global abundance of food would solve third world famine problems, realistically the complexity of social, political, religious and economic problems of these countries require alternative solutions to be sought when redistribution is just not possible. Provision of hardy, high yielding varieties of crop seeds may help address this issue. Crops resistant to drought and disease have the potential to provide a substantial agricultural alternative where otherwise famine would reign.

GM Foods and the Environment

The possibility and consequences of unintentional gene transfer to other plant species is a concern for many considering GM food crops. With respect to cross-pollination, every species has differing abilities and in Australia each crop is subject to case-by-case assessment by the Genetic Manipulation Advisory Committee (GMAC).

Potential for Transfer of Plant Genes

The transfer of herbicide resistance characteristics via cross-pollination with wild relatives has been demonstrated. The fact is this gene flow is unlikely to improve the adopter’s survival chances outside the agricultural area [10]. The resulting characteristic would only be successfully maintained where selection pressure renders its presence advantageous. Importantly this would not provide protection against other herbicides and is a similar scenario to the evolving antibiotic resistance of human pathogens. As we continue to develop methods of crop protection so too will the evolutionary processes change the susceptibility patterns of the target. The answer is to ensure diversity of treatment and avoid the development of resistance characteristics through proactive engineering and selection. As Dröge (1998)[11], eloquently points out, the issue isn’t the likelihood or the frequency of transfer since these possibilities are established, but rather it’s the nature of the genes transferred and the implications of possible transfer that should be the focus of biosafety considerations.

The prediction of rare hybridization events that may emerge in massive agricultural plots requires monitoring crop gene flow. These events also occur in conventionally bred crops and agricultural situations are subject to standard international requirements to prevent unwanted gene flow between selectively bred crop species [12]. Although the WHO considers the possibility of horizontal gene transfer to be vanishingly small, many research institutions are now responding to consumer concerns and removing herbicide or antibiotic marker genes or using alternatives in products intended for commercial use. Horizontal gene transfer is a proven phenomenon in the domains of bacteria, archaea and eukarya however transkingdom lateral gene transfer appears to be an extremely rare event [11]. It appears no one has been able to show that native bacteria are able to take up transgenic plant DNA in normal circumstances. However, when conditions and species are maximized in laboratory conditions to induce such transfer, it can be demonstrated that such mechanisms exist that would make the event possible [13].

Herbicide Resistance

Genetic modification of agricultural crops can achieve many goals. The most common to date include conferring resistance to disease and insects; tolerance to climatic extremes; improving quality handling and yield characteristics; and promoting herbicide resistance. Of all modified characteristics the last one has been a focus of concern. First consider the situation for crops without this GM resistance. These require a combination of alternative more toxic herbicides and more frequent spraying thus increasing the toxicological load in the environment. This has resulted in the massive loss of soil quality and associated biodiversity that is evident in the global deterioration of agricultural land.

Crops with the genetically modified herbicide resistance to Glyphosate (“Roundup”; Monsanto) enable early spraying that eliminates the need for any pre-planting herbicide treatments and greatly reduces the need of further applications during the growth period. This is achieved by giving the crops a head start over the weeds in the competition for sun, water and nutrients, where the weeds (by nature) would otherwise gain an aggressive advantage. As a herbicide Glyphosate is relatively innocuous, readily deactivated and degraded in the soil and crops. The WHO has listed glyphosate in the least precautionary toxicological category available for human and wildlife exposure. The point remains that all herbicide accumulation in the environment remains a cause for concern.

Traditional hybridization and selection techniques have already significantly narrowed the gene pool of many commercial species. Some discussion abounds regarding the even greater loss of diversity in genetic resources due to specific trait selection and the rapid selection techniques of genetic engineering. Genetic modification introduces new genetic material without disturbing the genetic makeup across the whole genome as in hybridization. In this way gene transfer can prevent the suppression of natural genetic exchange by allowing inherent diversity to be realised, so actually increase diversity within these species.

Preserving Diversity

Diversity in the gene pool is the cornucopia for the biotechnologist and as such the implicit imperative is its conservation. Genetic techniques are enabling the preservation of threatened and rare species. Natural resources can no longer be taken for granted. Many environmental concerns appear to be based on biotechnophobia as problems being raised are essentially equivalent to or less than those presented by conventional breeding or organic farming methods [14]. As research continues there is a growing international consensus that GM crops pose no greater threat than those produced by traditional breeding [7]. The terminator technology that induced embryonic abortion in GM plants produced wild opposition. However the non-reproductive outcome of these plants is little different to the sterile hybrids that are already in commercial use. Although this technology is not acceptable for the commercial market, the opportunity exists to learn from it and develop future useful applications [15].

GM Foods in Australia

In Australia the research, development and use of all genetic modification techniques is overseen by the Genetic Manipulation Advisory Committee (GMAC) under the auspices of the Commonwealth Government’s Interim of Office of the Gene Technology Regulator (OGTR - http://www.health.gov.au/tga/genetech.htm). Agricultural investigations include assessment of the crops to be modified and gene(s) to be inserted, including potential for unintentional impact on non-target and beneficial organisms. At present there are three GM crops grown commercially in Australia, insect-resistant cotton (INGARD) [16] and two flowers (Florigene’s “Moondust” and “Moonshadow”). Field trials of various other GM crops have been established under the guidelines of GMAC and the OGTR.

The Regulatory Environment

All GM food commodities grown or imported into Australia are subject to rigorous safety assessment to ensure they are as safe as their conventional counterparts. The Australia New Zealand Food Authority (ANZFA- http://www.anzfa.gov.au) is responsible for assessing GM foods under food standard A18 of the Food Standards Code. The assessment considers the genetic modification by examining the consequences of new gene products in the food; altered levels of existing gene products; data on host, donor and vector organisms; nutritional data and toxicological data. The safety assessment also considers the possible indirect effects of new gene product(s), possibility of gene transfer from ingestion, and potential adverse health affects [17]. Although many of these possible hazards may also be associated with conventionally bred food products, in most countries, including Australia, foods consumed for generations are not equivalently assessed on the basis that they have previously been assumed to be safe for consumption [10].

Under Standard A18 GM foods that differ significantly in terms of nutrition, allergenicity or food use must be labelled to indicate these differences for consumers. In August 1999 Health Ministers on the Australian New Zealand Food Standards Council (ANZFSC) resolved, in principle, to extend mandatory labelling requirements to all GM food, even those which are not significantly different to their conventional counterpart foods, in order to provide consumers with an informed choice in the purchase of food. In taking this decision, Ministers emphasized they had no concerns that GM foods pose a risk to human health and safety as there is a mandatory pre-market assessment of all GM foods by ANZFA. The Council is expected to decide on the form and extent of the labelling system in July 2000 following after considering public submissions on the issue and a full cost-benefit analysis [18]. It is unclear if the future Australian labelling system will differentiate between the levels of GM application in food, however there have been suggestions that a minimum threshold level of GM material may be applied above which labelling is required [19]. Regulations to this effect are in place in the EU for food products that attempt to avoid the use of ingredients derived from GM commodities [18]. How the Council will assess this level has not yet been revealed. A pertinent criticism of the regulations and debates of genetically modified products is their treatment as a homogeneous group [20]. For example in the U.S. products made from GM soybeans are not labelled as GM food as the final product is substantially equivalent to the non-GM product. However there is widespread support in many countries for comprehensive labelling of food where GM techniques have been used at any level of production regardless of whether there are any GM ingredients in the final product [21].

International Influences and Global Knowledge

There is no doubt that gene technology has the potential to change the future of global agriculture. Fundamental knowledge of genes and their products has substantially increased over the last decade. As knowledge continues to grow exponentially we are accruing a platform of information on the nature of genes, cell biology, genetically modified organisms and population ecology with respect to both human and environmental impacts. International standards are being introduced such as the code of practice of the Organisation for Economic Development (OECD) and protocols and principles of the World Health Organisation (WHO) and the Food and Agriculture Organisation (FAO) [4].

The protocols and principles of these organisations are the basis of guidelines used by ANZFA and the Office of the Gene Technology Regulator (OGTR – currently the Interim OGTR) in establishing Australian regulations and safety assessment of genetically modified products and processes. This growing body of knowledge, together with the global nature of scientific research and communication, ensures that genetically modified foods and components are scrutinized at a multitude of levels and from a multitude of perspectives. The Australia Consensus Conference on Gene Technology in the food chain [22] and the activities and consultation processes being pursued by Biotechnology Australia and the OGTR have provided Australians with an avenue to express their concerns and be heard.

Australia is at the beginning of the GM revolution. ANZFA had less than 2 dozen applications for GM crops at November 1999. These applications were for modification of 6 crops: soybean, canola, corn, sugar beet, potato and cotton. Foods on sale in Australia that use GM ingredients are derived from these six crops. However, not all ingredients derived form these crops are from GM crops. At this stage GM foods (derived from these crops) that have already been imported and are on sale in Australia have met the requirement of one or more of the following countries; USA, Canada, Japan and the European Union. Presently these products aren’t distinguished from their non-GM counterpart, however once the Australian labelling requirements are ratified, even ‘substantially equivalent’ GM foods will carry mandatory labelling. GM food products that are novel or substantially different, such as iron fortified rice or soybeans rich in oleic acid, will continue to require specific labelling as current law indicates.

Corporate Motivation

Concern has been expressed that the onus is on the food technology companies to provide scientific information on their genetically modified products. And the public has a right to be concerned about mass food production techniques following numerous other food (non-GM) scares such as salmonella and bovine spongiform encephalopathy (BSE). But biotech’ food companies are subject to domestic certification and approval, and their activities are scrutinized by ANZFA to ensure safety and regulatory criteria are met and following this public comment is sought. ANZFA can request additional information from the company at any time and may seek independent studies to confirm the accuracy of the product information. While opportunity exists to subvert safety regulations, both with GM and non-GM food, the cost to the corporation of market exclusion and community recompense hardly offers justifiable reward. Indeed, even companies like Monsanto are now supporting labelling criteria in the hope that transparency will reassure nervous consumers [23].

Research into the perception of the consuming public in Australia reveals ambivalence to GM foods [24]. It is a matter of choice and control. Many have concerns that stem from fear of losing fundamental decisions in our food choices. The control of food production by multi-national profit driven corporations is a commonly expressed concern. Ironically, it was this motivation that recently caused Gerber, Heinz, Kellogg, Nestlé and others to pull out of the GM market. The multi-national seed corporations are already grounded in trade with the primary producers; the GM product offers diversification as an alternative rather than an arbitrary purchase.

Middle Ground

The world is currently still discovering and coming to terms with the past transgressions of industrialization, and the possibility of global impact through new technologies is frighteningly real. Arguments swing from acknowledgements that we are all made from the same stuff, as intelligent creatures we can choose to enhance our environment with the best resources available, to the alternative view that this level of tampering with nature is unacceptable and it’s time we stopped interfering. The environmental impact of transgenic plants and the debate regarding trans-kingdom transfer of genetic information remains an ethical hotcake.

Consumer Power

Organic growers and non-GM growers have a new opportunity to provide untreated or conventional alternatives, and new market strengths will undoubtedly emerge in these areas. We can be sure that the conventional range of food products will continue to appear alongside the new GM and organic alternatives. The supermarket shelves will remain ever bountiful as the food corporations capture every niche of the food market in one way or the other. Control of the GM food market is by the purchasers, from the farm to the supermarket, and the choice is clearly the consumers.

The enforcement by the Australian regulatory bodies of mandatory labelling of all GM products is confirmation of this. The irony is that although the potential for toxicity and detrimental effects of additives and selective breeding is equivalent in conventional food production, similar labelling remains absent despite proven adverse effects from these methods [3].

It’s very difficult to consider the immense social impact of GM crops in a subsistence economy when one comes from a well-fed society. Similarly, poverty can only truly be understood when one is powerless to change their situation. It is this asymmetry of needs in the developing and developed countries, as commented on by Crompton [25], which requires serious attention in developing constructive agricultural advances. Agricultural biotechnology is not a panacea; it’s an opportunity to contribute to sustainable small-scale agriculture of developing countries [15].

Knowledge Sharing and the Consolidation of Excellence

As science continues to inform us we realise that the only absolute truth is that there is no absolute. The need for diligent testing and monitoring of genetically modified processes and products in the food domain, as in all other applications, requires that research is not compromised, regardless of ethical intentions.

That research will uncover adverse effects is not doubted – that is the point – to ensure thorough examination of potential commercial products. There is a place for activists - to ensure governments, industry and regulatory bodies are not slack. But clearly their responsibility extends beyond gratuitous publicity, to ensuring establishment and maintenance of thorough research programs rather than the destruction of the same. There is no denying an element of risk will always remain in genetic manipulation. Pleiotrophy (combined gene effects) works in strange ways and unpredictable combinatorial effects aren’t restricted to the level of the genome or to genetic manipulation. Continuing research and monitoring will ensure increasing knowledge and understanding in these areas. The debate over GM foods has produced a thoroughly delicious smorgasbord of opinions, emotions and facts. (Current benefits and problems of biotechnology in food production are summarized in a table at the end of the article.) The outcome is the international awareness of both consumer sensitivity to food issues and mistrust of regulatory procedures. To the credit of the activists, the outcry has ensured that international regulatory and safety standards for GM foods will be established which far exceed standards of conventional food evaluation, and help to ensure the pragmatic, responsible and safe integration of genetically modified foods into the global diet [25].

It is a reassuring situation that GM foods receive such thorough and ongoing examination although it is disappointing to see the media continue to sensationalize extremist opinions for the sake of a story. One can only hope that such awareness can stimulate attention and regulatory enforcement of other health issues that lurk in the shadows of the global community.

While Henry Ford may never have imagined the death and destruction the motor vehicle would cause, gene technologists are not in a position of such ambivalence. There is not much left (if anything) in the world that has escaped human impact.

The imperatives are now shifting as the earth moves towards its holding capacity. Improving practices to halt the loss in biodiversity and land degradation, to improve crop quality and yields are the drivers behind informed agriculture. Now is the time for proactive reconciliation with the earth through the consolidation of knowledge and excellence in agricultural farming and breeding techniques. The opportunity is here to harvest the best from organic growing and selective breeding that utilizes the full continuum of our knowledge.

Acknowledgements My sincere thanks to Prof. Ken Reed of the Queensland Agricultural Biotechnology Centre (QABC), Dr. Dennis Bittisnick of the Australia New Zealand Food Authority, Dr. Helen Kerr and Dr. Fiona Bisshop for their help in reviewing this article.

The references and tables for this article are not currently available online at this location.

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