Transgenic technology- the good, bad and the ugly

Transgenic technology- the good, bad and the ugly

Transgenic technology has emerged as one of the major bio-technological innovations of our time. Diverse clients of transgenic technology include fields of medicine to environmental management and crop science. Notwithstanding the fact that this technology has remained in eye of fierce policy and public debate, particularly with respect to its application in agriculture, there is no denial that transgenic innovations have opened new horizons of possibilities that never existed before. The various things that it can help us achieve almost seem science fictional and if not bizarre at times-, but they are not. For the first time in the whole evolutionary history of life on this earth transgenic technology has given one its millions of species- man-, the power to create new life forms. This appears like browbeating the process of evolution itself. What is it all about? Are the products of this technology all good to cheer about or are there reasons for worries too? But before we take a close look into that, perhaps we should try to understand the basic biology of the Gene and how it works.

The Gene and the Central dogma:

Cells of an organism’s body are like the bricks in a building. Inside the nucleus of a cell are the chromosomes- the thread like structures that pass on to the offspring from both parents. These chromosomes are again made of double helical threads called the DNA (Deoxy ribose nucleic acid). Genes are the short sections of DNA. DNA is a complex molecule and is made up of four types of biological bases- Adenine, Guanine, Thymine and Cytosine. Combinations of pairs of these bases constitute a gene. Genes are called the ‘functional unit because each combination of the base pairs contain information for producing a particular ‘amino acid’. Amino acids are the building units of any protein and as we all know- proteins are vital ingredients of an organisms physiology and responsible for large number of fundamental traits of an organism. Quite naturally then since genes regulate what kind of proteins would be produced they are called the functional unit of life too.

But we should also know perhaps a little bit about the mechanism of production of amino acids from genes. This mechanism of production of amino acids from gene is not a reversible process (i.e. it is not possible to make a gene from an amino acid) and follows a fixed pattern that regulates the flow of information from a gene to amino acid. This mechanism is known as the central dogma in molecular biology.

The classic view of central dogma states that the coded genetic information hard-wired into DNA is transcribed into messenger RNA (m RNA). This process is called transcription. The DNA can replicate via a process called replication. Each m RNA contains the information for the synthesis of a particular protein (or a small number of proteins) which is carried out through a process called translation. The diagram below shows an illustration of the central dogma in molecular biology.

Fig: The central dogma in molecular biology

Transgenesis:

Transgenesis is the process of transfer of genetic material (foreign) into an animal or plant genome. Thus, a transgene is a genetic material that has been transferred either naturally or by genetic engineering techniques. This transfer process is called transfection. The introduction of a transgene has the potential of changing the phenotype of an organism.

Various vectors like plasmids are used in transfection. The plasmid is a small DNA molecule that is physically separated from and can replicate independently of the chromosomal DNA within a cell. These plasmids used in transfection commonly include p RSV for fishes, p BR322 (used as shuttle plasmid vectors). Other than plasmids various other vectors which are used include BPV vectors, Retrovirus vectors, Polyoma virus vectors, Vaccinia virus vectors, P element vectors (transposable element in Drosophila) and Bacculovirus vectors.

Transgenic Products- the Good:

Genes have been transferred into animals with an objective to obtain a large scale production of the proteins encoded by these genes in the milk, urine or blood of such animals. Such animals are called bioreactors and the approach is referred to as molecular farming or gene faming. For example, cattle, goat, sheep and swine are used for large scale production of proteins from human genes (such as alpha 1 antitrypsin, tissue plasminogen activator, blood clotting factor IX, and protein C) expressed in the mammary tissues of these animals.

A special case of gene transfer aims at alleviating or even eliminating the symptoms and consequent problems of genetic diseases. In this approach, normal and functional copies of the defective gene (that produced the genetic disease) are introduced into the patient. This is called gene therapy. The most logical step that scientists have taken is trying to introduce genes directly into human cells, focusing on diseases caused by single gene defects such as cystic fibrosis, haemophilia, thallasemia and sickle cell anemia. However, this has proven more difficult than genetically modifying bacteria, primarily because of the problems involved in carrying large sections of DNA and delivering them to the correct site on the gene. Today, most gene therapy studies are aimed at cancer and hereditary diseases linked to a genetic defect.

Specific transgenic animal strains or lines are created to fulfill specialized experimental and/or biomedical needs. Often used is the “knock out” mice strain in which specific genes have been replaced or knocked out by their disrupted counterparts through a process of homologous recombination.

It is now believed, that in the next two decades 300 000 lines of transgenic mice will be generated. Of particular interest is the application of such transgeny in the medical field. The  study of the function of the human genome is now carried out using transgenes -- adapting animal organs for transplantation into humans, and the production of pharmaceutical  products such as insulin, growth hormone, and blood anti-clotting factors from the milk of transgenic cows. One of the most promising avenues of transgenesis is the possibility of the treatment of genetic diseases to which many succumb. In this regard, gene therapy will hold particular value in the years to come. Even though it is not a widely accepted remedy, the lives of the people who fall prey to genetic diseases like haemophlia and thallasemia lie in the hope of this promise.

Transgenic products: the Bizarre:

A recent transgenic plant project, known as the “glowing plant project,” incorporated a gene from a firefly into a houseplant, creating plants that display a soft illumination in the darkness. One of the proposed goals is to create trees that could illuminate streets and pathways, thereby saving energy and reducing our dependence upon limited energy resources. However, the public release of such plants has sparked a heated debate centered around potential environmental impacts of introducing highly genetically engineered plants into natural ecosystems.

BioSteel® is a high strength, resilient silk product created by inserting the genes from a silk-spinning spider into the genome of a goat’s egg prior to fertilization. When the transgenic female goats mature, they produce milk containing the protein from which spider silk is made. The fiber artificially created from this silk protein has several potentially valuable uses, such as making lightweight, strong, yet supple bulletproof vests. Other industrial and medical applications include stronger automotive and aerospace components, stronger and more biodegradable sutures, and bio-shields, which can protect military personnel and first responders from chemical threats such as sarin gas.

Transgenic Products: the Bad and the Ugly:

Alongside the applications of transgenic in medicine and bizarre attempts to produce light with glowing plants attempts are on to apply this technology in crop science. One would see a novel initiative in this as answer to existing and growing demand for food. But there are perhaps more than that meet our eyes in this initiative. In our country itself market approval has already been given to transgenic cotton (Bt Cotton). There was an attempt to market Bt Brinjal too but a moratorium was slapped on its commercial release after large sections of the society including scientists and farmers raised serious objections.

Through rest of the sections we shall have a close look at the transgenic crops or Genetically Modified (GM) crops and why are there so much of debate on this. There is a major view within the progressive movement that the GM crop technology should not be opposed as such since there is nothing wrong with the technology and opposing it would be anti-science & technology. This view suggests that progressive movement should press for freeing this technology from the hands of monopoly trans-national agencies like Monsanto and DuPont and should fight for increased indigenous engagement in GM crop research. It is hence all the more important to analyse what might not be all that right with GM crop technology after all and  we shall try to argue the position people’s science movement should adopt with regards to the issue of GM crops.

Transgenic plant was first produced in 1982 was a herbicide resistant tobacco and the field trial of this plant was carried out in  France and the USA in 1986. In 1987, a Belgian company named Plant Genetic Systems first developed genetically engineered pest resistant tobacco plants that bore toxin producing genes from a soil bacteria (Bacillus thuringensis) by expressing genes encoding for insecticidal proteins. The People’s Republic of China was the first country to allow commercialized transgenic plants, introducing a virus-resistant tobacco in 1992, but this was withdrawn from the market in in 1997. Subsequently, in 1994 a genetically modified tomato (FlavrSavr) with longer shelf life was approved for sale in USA. Approval for transgenic crop in European Union first came in 1994 for herbicide resistant Tobacoo that was the first transgenic developed in 1982. In 1995, Bt Potato was approved for marketing in USA. Subsequently marketing approval in USA also came for a rape plant variety canola with modified oil composition (Calgene), (Bt) corn/maize (Ciba-Geigy), herbicide resistant cotton (Calgene), Bt cotton (Monsanto), soybeans resistant to the herbicide glyphosate (Monsanto), virus-resistant squash (Asgrow), and additional delayed ripening tomatoes (DNAP, Zeneca/Peto, and Monsanto). As of mid-1996, a total of 35 were marketing approvals were given for 8 transgenic crops and one flower crop of carnations, with 8 different traits in 6 countries plus the EU. In 2000, a variety of rice that can synthesise Vitamin A- the prevention for blindness was developed. This was termed the ‘Golden Rice’!

Genetically modified plants and evidence of scientific uncertainties 

The main limitation of this technology is the availability of preliminary knowledge about the role of gene in determining a given trait and is, at present, only applicable for traits that are ‘determined’ by one or a relatively small number of genes. To date, most applications that have reached the field involve the use of heterologous genes (i.e. genes from other organisms) to engineer various adaptive traits as herbicide and insecticide resistance where the window of opportunity has been limited by the operation of biology / nature prevailing over the resources of farmer in practice sooner than the state of art in genetic engineering expects the problems to hit back.  

Further, it is necessary to recognise that delivery methods like the “gene gun”, or more or less scattered shot technologies, are still being used in genetic modification technology. The place of insertion of new genes into the plants’ genome is not the result of a finely targeted process yet and hence the probability that the target gene would carry along extra genetic load when it gets inserted. Furthermore, the biological activity of newly inserted gene sequences has to be enforced artificially. The plants’ own gene regulation has to be knocked out (partially) to avoid silencing the additional gene constructs. As a result, it has been observed that unintended biological interferences can also have various effects at the level of the genome, cell metabolism and or the whole organism[1].

Toxicological and health impacts can be serious. One has to take into account unintended components caused by occasional interference of the plants’ metabolism. Environmental impacts cannot be taken lightly. The relevant risks are not of a steadily fixed nature, they involve dynamic processes involving factors like the growth of the plants and various environmental influences. Exposed to external stress factors, genetically engineered plants can also exhibit unexpected effects not noticed before (Matthews et al, 2005). There is also the problem of unintended gene transfer; special cause for concern is the fact that the spread of the artificial gene constructs via and other escape routes cannot be prevented.  All in all one has to deal with a complex matter of ecological, biological and health related issues which is dependent on a broad range of additional external factors which are not fully understood in all details.

In a much talked about piece in Science, Dominigo (2000) showed that while there are many opinions on the GM crop issue, data on the potential health risks of GM food crops are rare; even though these should have been tested for and eliminated before their introduction. Our present data base is woefully inadequate. As this article pointed out then, there are hardly any scientific literature on the the GM related health risks published by the scientists working in the Biotech companies. If they have tested for the toxicity and allergenicity of GM crops, then why haven’t they been publishing it? Since Dominigo’s article is a decade older, we looked for the current status of the same using the same search procedure as Dominigo’s and found the same pattern in more contemporary published literature. Quoting Dominigo-, “Moreover, the scientific quality of what has been published is, in most instances not up to expected standards. If, as claimed, our future is dependent on the success of the promise of genetic modification delivering wholesome, plentiful, more nutritious and safe GM foods, the inescapable conclusion of this review is that the present crude method of genetic modification has so far not delivered these benefits and the promise of a superior second generation is still in the future.” Obviously then quoting Dominigo again, “We need more science, not less”.

The underlying principle of GM crop risk assessment has been a so-called “comparative approach”, which tries to draw a comparison between the genetically engineered organisms and their counterparts produced in conventional plant breeding. In this approach, conventional protocols use the concept of “familiarity” for the risk assessment of the cultivation of transgenic plants and “substantial equivalence” for the risk assessment of food and feed. The problem with such an approach is that if-due to insufficient scientific methods-no substantial differences can be found between the transgenic plant and its comparator, the product is likely to be categorised as being safe. It is important here to know that methods especially relevant in the analysis of the proteom and the metabolom have not yet been developed sufficiently to be used as standard procedures in risk assessment (EFSA, 2007 a), despite these methods having been seen as decisive tools.

‘Substantial equivalence’ (SE) between the transgenic crops and conventional crops (meaning, two varieties are so similar to one another that they can be taken to be same) are often argued by the proponents of universal value of GM crop technology. The objections to this SE argument are the following:

1. There is no specific, statistical basis for the standard (Brunner and Mayer 1999). Substantial” is an adjective rather than a statistical parameter like an F value or a p value, which begs the obvious question: How different is acceptably different versus unacceptability different?
2. GM and conventional crops cannot be compared for the possible consequences to food quality and composition due to unintended effects, either predictable or unpredictable ones. How can one investigate unintended effects using directed testing methods?

It can hence be argued that, instead of making the GM varieties the only subject of analysis, we require a deeper understanding of naturally occurring variations that would also represent the range of consumer acceptable variation.

A completely different concept of risk assessment would apply if the underlying hypothesis took into account the fact that transgenic plants are derived from a technical process that cannot be compared to methods used in conventional breeding. The basic difference between conventional breeding and genetic engineering is becoming more and more evident because it can be shown that the mechanism for regulation of the genome is far more complex than was estimated some years ago. Today the organization of the genome is much more defined by networks and (quantitative) synergies of gene clusters than by the function of single genes. Wentzell et al. (2007) for example indicate this development including its consequences in the case of plants when they state “Most phenotypic variation present in natural populations is under polygenic control, largely determined by genetic variation at quantitative trait loci (QTLs). These genetic loci frequently interact with the environment, development, and each other, yet the importance of these interactions on the underlying genetic architecture of quantitative traits is not well characterized”. In the light of such advances in scientific understanding, we understand that this uncertainty would be better reflected in the development of hypotheses on the risk assessment of the transfer of isolated genes in the precautionary approach.

This new insight matters also because in the case of GM crops the new genetic information and its expression in the cells is forced into the plants by such technical means that knock-out partially the normal mechanisms of gene regulation. Invasive methods like this are not used in conventional crossings or mutation technologies. New genetic information obtained in conventional breeding gets used if it fits with the existing genetic background of the plants. But for the risk assessment of genetically engineered plants it is crucial not to deny the basic distinction between methods for breeding and technical construction of genetically engineered plants. While conventional breeding uses existing biodiversity and its potentials developed by evolution over a long period of time, genetic manipulation tries to enforce a technical program without obeying the rules of normal gene regulation. The changes associated with genetically engineered plants are not restricted to specific regions in the genome. The findings of Batista et al (2008) show that the assumptions that changes in genetically engineered plants to be restricted only to the specific trait inserted, are not based on scientific facts.

Horizontal gene transfer (HGT) problem looms large

The transgenic technology is essentially a technology wherein genes are transferred across non mating species. This transfer is essentially horizontal as against vertical transfer of genes from parents to progeny through sexual reproduction within the same species. The issue is not whether such horizontal transfer is unnatural as some voices against GM crops that Purkayastha and Rath mentions, but the point precisely is that-, it is not. The point is different; HGT is known to have affected the evolutionary process in the past (Syvanen 1985, Doolittle et al. 2003, Rivera and Lake 2004, Bapteste et al. 2005, Koonin 2007, Richardson and Palmer 2007, Keese 2008). Therefore, HGT can significantly impact genetic diversity at least among phylogenetically close species and can promote novel adaptations among organisms, thereby also tinker with the natural evolutionary process. It has also been said that in the short term HGT has been a major contributory factor behind rapid spread of antibiotic resistance amongst pathogenic bacteria in the last 50 years (Mazel and Davies, 1999). There is a growing body of literature that attributes incidences of increased virulence to HGT (Derbise et al., 2007; Friesen et al., 2006; Mild et al., 2007). Following table illustrates some short term and predictable adverse impacts of HGT from GMO (after Keese 2008):

Table 1.

Impact category	Impacts	References
Adverse Environmental Effects	Enhanced pathogenicity or virulence in people or animals	Kleter et al 2005
Unpredictable & unintended effects	Introduced genes from a GMO to multitude of other species, some of which are potential pests or pathogens, and many organisms are yet to be identified and characterized. Introduced gene might escape to indigenous bacteria and can alter its ecological niche characteristics. Difficult to predict the outcome but is a strong possibility.	Prescott et al, 2005, Heuer and Smalla, 2007
Genomic disruption	More complex genomes, e.g. that of higher organisms are more intolerant of change and may lead to genomic instability. Possible to measure.	Ho et al 2000, Woese 2004
Uncontrollable management	HGT from GMO would create new GMO. This new GMO might lead to adverse effects that are not controllable through management measures permitted in the license while releasing the original GMO	Keese 2008

HGT and Centre of Crop Genetic Origin

HGT assumes added importance when it comes to genetic modification on crops at the site of its origin. Crops at the centre of their origin are likely to have more number of phylogenetically related species. HGT has been seen to be increasing with decreasing genetic distances and vice versa (Beiko et al 2005, Majewski 2001, Fraser et al 2007, Bonnet et al 2005) meaning crops at the centre of its origin will have more chance of transferring novel genes into its related species and landraces. The most noteworthy case in support of this apprehension is that of GM maize in Mexico, where fragments of CaMV 35s promoter from genetically modified maize, commonly used as a construct to boost up gene expression of inserted gene in plant genetic modification, was found to be contaminating Maize landraces. This discovery by Quist and Chapela, two University of California, Brakeley scientists was reported in Nature (Quist and Chapela 2001). An independent study by Mexican government later corroborated this finding.

HGT and Public Health concerns

There is a growing body of evidence to suggest that the genetic material from CaMV virus (Cauliflower mosaic virus) mentioned in the Mexican incident, as a transgenic construct for plant genetic modification is potentially hazardous due to a number of reasons and has serious public health bearing. The CaMV 35s promoter is found across the living world and is even found in humans. In 1999 it was discovered that this promoter has ‘recombination hotspots’ where it tends to break and join up with other DNA (Hull et al. 2000, Ho et al. 2000). It is now understood that CaMV 35S promoter will be extra prone to spread by horizontal gene transfer and recombination and can even interact with human genome. Hence, so far the present state of technology goes; search for a safer gene expression promoter is definitely in order even if genetic modification technology in plants is to be pursued. The health risks associated with this are the following:

1. Antibiotic resistance genes spreading to pathogenic bacteria.
2. Disease-associated genes spreading and recombining to create new viruses and bacteria that cause diseases.
3. Transgenic DNA inserting into human cells, triggering cancer or hitherto unforeseen and uncertain other expressions.

Genetic stability

Evidences from a number of studies indicate that transgenes are inherently unstable compared to natural DNA and are more likely to break up and rejoin. Transgenic DNAs are also designed to break species barrier through flanking them with recombination sequences which enable them to jump into genome and is hence potentially more prone to horizontal transfer. Worse, since they come from a wide variety of sources, e.g., pathogens, allergens etc., in case of these fragments sitting pretty in the host get into any homologous arrangement with the donor genome due to similarity in base sequence, the probability of HGT increases many fold, since homology enhances HGT (Primrose & Twyman 2006). The recent discovery of ‘recombination hotspots’ both in plant as well as in human genome is indicative of the risk of inserted DNA fragment around these hotspots and hence would be further prone to expressions that were not intended primarily.

Towards a Precautionary Assessment Principle:

We have a choice to make from the four different approaches to assessment; each approach being designed to gather the information necessary for making adequate and prudent governance decisions in different contexts.

1. If a significant harm is expected with almost certainty, then, subject only to consideration of any over-riding justification, they are assigned directly to preventive measures.
2. If the threats in question are minor and quantitative data about probabilities and magnitudes is either available or is to be produced, then they should be assigned directly to the approach of risk-based assessment.
3. But if we are unable to allocate threats to straightforward preventive measures or to risk-based assessment, then more comprehensive assessment procedures are recommended. If any scientific uncertainty has been identified, then the subsequent approach to assessment is precautionary assessment.
4. If socio-political ambiguity has been identified, where the problem lies not with probabilities, but in agreeing on the appropriate values, priorities, assumptions, or boundaries that apply in defining the possible outcomes, then a process of concern assessment is adopted in subsequent assessment.

Both conditions (uncertainty and ambiguity) can apply at the same time and for the same assessment candidate. We argue that in the case of Bt crops, both approaches, i.e. the precautionary assessment approach and the concern assessment approach need to be combined.       

The technocratic way of framing the assessment protocol of risks involved in the case of GM crops (wherein “objective science” is seen to directly inform policymaking), is quite inadequate and ethically inappropriate. The introduction of GM food crops cannot be handled in terms of merely the conventional risk assessment approach that refers to a situation where it is possible to confidently quantify both the magnitudes of and the probabilities for a defined range of outcomes (such as forms or degrees of harm). If the intractable circumstances include also conditions of ‘uncertainty’ (where possible outcomes are clear but difficult to quantify probabilities), ambiguity (where the problem lies not with probabilities but in agreeing on the values assumptions and boundaries that apply in defining the possible outcomes), and ignorance (where neither probabilities nor outcomes are fully or confidently characterized); then the precautionary principle based technology regulation is a must in our view. Conventional risk assessment would leave residual uncertainties unaddressed. A more comprehensive approach to assessment is preferable to unconstrained reliance on conventional risk assessment methods.

Since the precautionary assessment approach can address a set of more intractable circumstances under which various forms of incertitude render such quantification incomplete or problematic, it is far more appropriate to adopt this approach for the regulation of technology of GM crops in India. Argument that familiar safety testing protocols are sufficient to serve societal needs well because GM crops carries non-catastrophic consequences, is certainly not an appropriate objection. As far as the demand for the implementation of precautionary assessment approach based regulation is concerned, it is not pertinent that the technology of GM crops carries non-catastrophic consequences. What is important is that there are areas of uncertainties, ambiguity and elements of ignorance in the case of GM food technologies.

Although the basket of technologies to be championed by the progressive movements deserves to include certainly the technology of agro-biotech and genetic engineering (which might also involve genetic modification for the development of transgenic technology); the progressive movements should not reject or overlook the precautionary approach to commercial introduction of the GM crops. The people’s science movement need to struggle for a comphrensive framework for the assessment, management and communication of technological risks to mobilise their own basic classes in a sustainable way. This framework is essential because we are going through a neo-liberal phase when system of public-private partnerships (PPPs), the new trend in the division of the innovative labour between public and private entities is becoming all pervasive in agricultural research; and the public sector in science and technology (S&T) is being made to come under the greater influence of big business and global corporations.

The precautionary assessment approach requires to be pressed for as other choices do exist for immediate purposes and can be selected suitably from the basket of technologies being developed with the efforts of modern science and technology. Efforts going on in the field of ecological approaches to agriculture are equally modern and can even serve the basic classes better whom the people’s science movements hope to mobilize for a better future for the agriculture sector in India. It is time now for the

Further, the implementation of precautionary assessment approach based regulation means more directed research, improvement in quality of risk assessment and participation of the people in assessment, evaluation and management. There is nothing to be feared from the use of a wide variety of broad based approaches at the earliest stages in innovation or policy making process, extending beyond conventional quantitative, expert-based techniques of risk assessment. The precautionary assessment does not bar introduction of technology of GM crops per se forever. We are not asking the Government of India to stop scientific and technological research on the development of technology of GM crops. Decisions regarding the introduction of GM crops are required to be undertaken case-by-case, which is fully permitted by the precautionary assessment approach to regulation. Given the basket of technologies that are becoming available in respect of habitat management, systemic application of cultivar mixtures in integrated farm systems, agro-forestry and biological control that can potentially address even the issue of productivity; there is no reason to rush into genetically modified crops without a going through a case by case precautionary assessment protocol.

Advancement of molecular biology has allowed us to delve into a great many mysteries of life on earth and everyone sees the potential of this science breaking new frontiers in solving problems that has plagued humanity for centuries. But obviously the objective approach would be to weigh options that are less hazardous, more certain and at the same time are potential technologies that can solve problems at hand including the present crises in agriculture. We need to compare any new technology with the best available technology or practice at hand before we clutch on to it. A good example would be marker assisted plant breeding; a technology option that also makes the best use of our progressing knowledge of molecular biology but is essentially devoid of the hazards associated with GM.

Marker aided breeding and other approaches

Traditional plant breeding has essentially involved incorporation of desirable traits in a plant through phenotype based selection. Genotype based selection would involve zeroing on the gene of interest and incorporating the gene in the desired plant race through hybridization. However, this potential could not be realized due to lack of marker genes. Discovery of a wide range of genetic markers since the late 1970s has made this possible since it is now possible to detect genes of interest with the aid of their associated markers (Ruane and Sonnino 2007). Pioneering work by Peterson and his colleagues (Paterson et al 1988) in tomato led the way. For example a plant having a gene that provide resistance to a particular disease can be selected with the help of the particular disease resistant gene’s markers and can then be hybridized to bring about disease resistance in the desired plant variety. An excellent overview of this technology and its potential can be found in the FAO publication on Marker assisted selection (FAO 2007).

Learning from the experience of other countries

We can also learn from the practice of the member countries of European Union which have been made to deal with the genetically engineered maize (MON810). More than eleven countries have chosen to withdraw the permission for the commercial introduction of MON810 on the basis of the new doubts about safety that have now surfaced after allowing the cultivation of Bt toxin producing maize for a period of about ten years. It is however to be noted that so far this Bt toxin producing maize has been the only genetically engineered crop allowed to be commercially cultivated within the EU. MON810 was granted market authorization for the EU in 1998. The German government prohibited the cultivation of MON810 in April 2009. It was done on the basis of the new publications that showed negative effects on organisms such as ladybird larvae and water fleas.

An overview of recent publications shows that the effects observed on these and other non-target mechanisms in the case of MON810 indicate a general problem. Until now it was supposed that the toxins as produced in the plants can only fulfill their deadly mission under conditions as met in the gut of the larvae of certain insects (Lepidoptera). Specific receptors, described as ‘target organisms’, occurring in the gut of these pest insects (and in the case of MON810 the corn borer especially), are needed to activate the toxin. In contrast, so called ‘non target organisms’ are supposed not to be endangered because those receptors cannot be found. Recent publications show that the toxin produced in the plants is different in its structure from the natural occurring Bt toxin and thereby also changed its biological activity. Several publications show that a coherent theory for the mode of action of Bt toxin (and the role of receptors) is missing. Recent research shows that the selectivity and the efficacy of the Bt toxins can be quite substantially influenced by external factors. 

It is but to be noted that although Chinese Agriculture ministry has certificated two strains of GM rice, it would still take a considerable time before the Bt rice grains are found on the shelves (Shan Juan and Wu Jiao, 2010). As has been announced by Chen Xiwen, a member of the Chinese People's Political Consultative Conference (CPPCC) and deputy director of the Central Rural Work Leading Group of CPC, the products would need to be certified by government agencies from the health and quality inspection sector, any of which might stop the entry of the food grains into the market. As has been asserted out by Xiwen, “the certificates, based on fair safety evaluation, won't mean GM rice would be commercially planted immediately. It will require production trials and registration.” Wei revealed that the applications for the two rice strains were filed 11 and 6 years ago respectively.

Are we saying no to GM then?

The controversy over Bt brinjal brought to the fore the issue about the choice and selection of a technology in tackling serious concerns in Indian agriculture. Bt technology was pushed to tackle a biotic stress namely the pest problem. This technology was pushed at a time when the nation was also taking notice of the phenomenal success of non pesticidal management (NPM) in Andhra Pradesh. Through NPM, a package of ecological techniques of tackling pests, about 420 villages in A.P. successfully managed pest in about 23000 acres covering 10 districts. This experiment has shown that a range of biotic stresses can be overcome through ecological management of natural biological resources. But there are issues involving abiotic stresses like drought, water logging etc for which answer may still be sought within GM technology. For example, instilling the vigour of the drought tolerant C4 plants like sorghum in C3 cereal crops like paddy or wheat through genetic modification will definitely be a welcome intervention.

Keeping these in view, risk assessment of genetically engineered plants should be conducted without preconditions such as assumptions of similarity (familiarity, substantial equivalence) between transgenic plants and plants derived from conventional plant breeding. Transgenic plants have to be seen as technically derived products with specific risks and have to be subjected to comprehensive risk assessment per se.

A mandatory step-by step procedure, as it is now being evolved in EU, with screening process introduced for the purpose of framing of criteria and threshold of evidence required, should be introduced. To avoid unnecessary feeding and field trials, testing in contained systems should be given enhanced weight. Tests need to be recommended where considered necessary, for stress exposures of transgenic plants under defined conditions (crash tests), for metabolic compounds profiling under different stages of plant growth and environmental conditions, simulations of different ecological systems and interactions with different external factors. Needless to say, case by case method has to remain in vogue for the risk investigations required to be undertaken each time.   

Finally, let the mastery of technical construction program based on scientific advances that we have referred to be allowed to mature. Precautionary approach based risk assessment is consistent with the development challenge that the progressive movement faces today in India.  Risk governance includes matters of institutional design, technical methodology, administrative consultation, legislative procedure, and political accountability on the part of public bodies, and corporate responsibility. It also includes more general provision on the part of government, business and civil society groups for building and using scientific knowledge, for fostering relevant technical competences, and for promoting social and organizational learning. It is quite clear to us that the demand is growing in the country among very different kind of publics for a more effective, efficient and, at the same time, a balanced and fair regulatory process which is also characterized by more transparent and participatory decision making procedures. Let the people’s science movements champion the democratic agenda and not fall into the trap of productivist and technocratic approaches to assessment.

In conclusion, we understand that the ideological debate is not just limited to the anti- and pro-transgenic camps. It is also a debate around how the decision regarding the introduction of genetically modified (GM) transgenic food crops needs to be approached by the people’s science movements.

Notwithstanding the fact that areas under GM crops is on the rise, the scientific concerns that were raised way back at Asilomar conference on Recombinant DNA technology in 1975 are still alive and valid. As long as these concerns, categorized broadly into environment and public health, are not addressed and a consensus is not arrived at within the progressive scientific community, these issues would definitely deserve to be revisited over and again and would have to be reviewed against fresh scientific literature.

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[1] The changes associated with genetically engineered plants are not restricted to specific regions in the genome. This process impacts the genome and cell regulation on several levels. See for details Batista et al., 2008, Clark et al., 2007, Wilson et al. 2006, Wentzell et al., 2008.