Genetically Modified (GM) crops are in the limelight again as the Genetic Engineering Approval Committee (GEAC) in India recently permitted commercial cultivation of Bt-brinjal. This brinjal contains the pesticide gene from Bacillus Thuringiensis and has been developed by Mahyco Monsanto Biotech, a joint-venture between Maharashtra Hybrid Seed Company and the US seed colossus Monsanto. GEAC is supposedly India's highest regulatory body for genetically engineered plants, but its very name proclaims its charge - to give approval to genetically engineered substances, as opposed to being a disinterested regulatory body.

Given all the confusion regarding GM crops let us recapture a few lessons we have learnt and know for sure in the area of food security and agriculture. Biodiversity is critical to sustainable, healthy agricultural ecosystems; a farmer's ability to control agricultural productivity through ownership of seeds, access to markets and reasonably secure livelihoods is important; and to ensure food security, storage, distribution and purchasing power have to be part of the picture. For instance, India imported lentils recently to tide over its needs. Some agricultural experts suggest that improved storage methods would have made these imports unnecessary.

In essence, we need a systems approach to agriculture and food security instead of viewing them as requiring mere technical fixes. Thus while various technologies and innovations - such as better rural credit systems, improved methods to capture and store rainwater, and development of implements to enable women to work more easily in the fields - will remain crucial to agriculture, these developments must support the critical elements.

Science vs. anti-science?

What has been of particular interest in this and past debates on the subject is the way in which those who oppose GM crops are painted as being against science (see for instance, the editorial in The Hindu on 21 October, 2009 or Starved for Science by R Paarlberg). There is a blatant attempt by GM promoters to polarise the discussion and manufacture a science-vs.-antiscience debate. All those who oppose GM crops are neither anti-science nor luddites. Indeed, many scientists have been, and still are, critical of GM for a number of good reasons. Scientists and scientific academies, including the National Research Council of the US National Academy of Sciences, have expressed serious concerns regarding the scientific rigour of experiments and the impacts of GM crops, especially on biodiversity.

Those who support GM crops generally believe that science and technology can solve most problems, and see crops as requiring tinkering to improve agriculture. It is such short-term and piecemeal thinking that led to the excesses of the Green Revolution causing damage to soils, depletion of ground water and other harms to ecosystems. There are other supporters of GM who continue to believe that private production of goods and services is inherently superior to public ones, even as governments have been bailing out the private sector in the last year! And then there are those who have financial gains to make if the GM industry prospers.

Let me compare the GM debate with the other major scientific debate - global warming. While scientists who work on climate change and global warming rightly embrace the precautionary principle, many who work in the area of GM plant technologies abandon it altogether. A charitable explanation is that this may have to do with differing perceptions of risk in each case. Perhaps global warming is seen as a serious threat to the entire world, and GM crops may not be understood in the same way. Moreover, some benefits have been attributed to these crops by promoters, making it harder for people to reject them.

But while the naysayers of climate change have now been marginalised through more research and data, those who are concerned about GM crops have been silenced through smear campaigns launched against them. Some of the scientists, like Arpad Pusztai, who raised questions regarding the health effects of GM crops, have had their careers turned upside down. In order to learn about the tentacles and might of agribusiness, one must ask Ignacio Chapela from UC Berkeley about his gut-wrenching tenure battle, which followed his publication in Nature on the contamination of wild strains of Mexican maize by GM maize

The mere use of technology does not make an approach scientific, but this is a common fallacy even among scientists. Good science is characterised by transparency and falsifiability. These do not figure in GM. Instead, faith, the antithesis of science, features in a big way. There are few peer-reviewed journal articles on GM crops. When companies make claims about various positive contributions from their engineered crops, their statements cannot be verified or tested independently. Policymakers and even other scientists who work in the same area have to accept the results on faith.

Earlier this year, an anonymous public statement was signed and submitted to the U.S. Environmental Protection Agency (EPA) by 26 leading scientists, entomologists who work with insects that infect corn. It stated that scientists are unable to conduct independent research on GM crops as patents prevent full access to research materials and the ability to grow and study these plants. As a consequence, the scientists state, the data that the Scientific Advisory Panel of the EPA has available to it is unduly limited. This means the claims of GM proponents cannot be verified independently or indeed be falsified.

GEAC is supposedly India's highest regulatory body for genetically engineered plants, but its very name proclaims its charge - to give approval to genetically engineered substances, as opposed to being a disinterested regulatory body.

• Too risky to tolerate • Genetically engineered spin There is general agreement among scientists and academics on the adverse effects on biodiversity as a result of cross-pollination from engineered to non-engineered crops. Still, field trials for GM crops in unmarked areas blow caution and engineered pollen to the winds in closely cultivated fields in India.

The potential damage to human health from GM crops has been shown quite clearly in a few animal systems, but perhaps needs further study. There is good peer-reviewed published evidence to show that Bt toxins are both immunogens (a substance that provokes an immune response) and immunoadjuvants (a substance that enhances immune response) for mammals. Moreover, studies have shown that Bt toxins bind to the mammalian small intestine and have effects on its proper functioning. The concerns raised by the use of viral promoters, which are hotspots for genetic recombination, the use of antibiotic resistance genes, and strong gene promoters (sequences that facilitate the transcription of a gene) to ensure that the foreign genes are expressed, have already been highlighted by many scientists.

The science behind genetic engineering of plants is itself outdated as it continues to view a gene as a single self-contained unit of DNA sequence that transfers information linearly to RNA (ribonucleic acid) and then to proteins. It has now become clear that this picture of gene expression is simplistic and incorrect. There is a complex array of interacting factors that influence gene expression. For instance, even sequences of DNA located at a distance from the gene in question can be involved in regulating it as can other cellular and environmental factors. Further, RNA and protein play a far more important role in gene expression than previously believed.

What this implies is that simply introducing a DNA sequence into a plant and expecting a complex trait to be successfully transferred is not justified. This explains why even after decades of experimentation with numerous traits, only a couple of characteristics (the pesticide gene and herbicide tolerance) have been transferred to plants and that too, many would argue, unsuccessfully.

By any means necessary

The truth is that agribusiness has been doing its best to gain control of food security for profit using many different tactics and it is supported from various quarters. While political coercion and economic pressure have been working to open some European markets to a few GM crops, the vast majority of the people and most of the countries in Europe remain doubtful about GM foods. In case of large-scale industrial farms (which receive generous subsidies from public coffers) in the US, GM crops seem to make farms easier to manage.

The conversion of farmers to using engineered crops in other parts of the world may work for a few seasons, but most of them find that pests grow resistant to the Bt gene compelling the application of more chemicals. This is reported to already be happening in the case of Bt cotton in India. The companies are beginning to respond to the problem by inserting more Bt and other pest-resistant genes.

The debate in GM plants is even more deeply suffused by vested interests than that on global warming. In addition to impeding research, companies also exert their influence on review and approval by way of revolving doors between agribusiness and regulators. Furthermore, outright threats came to light in the UK in 2003 when the government decided to hold panels to review GM foods. According to The Guardian "Dr Andrew Stirling, of Sussex University and a member of the Government's GM science review panel, was warned by a leading member of the scientific establishment his career would be ruined unless he stopped questioning the technology's safety. The pro-GM scientist tried to get Stirling removed from a research project by approaching its funders."

Another leading academic reported that he resigned from the science review after fearing that his funding might be withdrawn. "Professor Carlo Leifert, of the University of Newcastle, also felt it was improper that an employee of GM giant Monsanto had been allowed to draft a key chapter on the safety of GM foods for the science review." Individuals from biotechnology companies often occupy key decision-making positions in regulatory agencies. In India conflicts of interest and straightforward charges of corruption have been made in the appointment of GEAC members.

The battle lines are drawn, but not as visibly as they have been in the case of global warming. Developing countries such as India with its large population and huge potential for markets are very attractive to agribusiness. In India where the vast majority of the people still depend on agriculture for their livelihood, and where diverse ecoystems and crop varieties still thrive, control over food security needs to be a top priority that is not be handed over to anyone: corporations, governments or even civil society for that matter.

The state of Orissa has come out and taken a stand against GM crops. Orissa has over 100 varieties of local brinjal and those may be affected by GM contamination. India might be where the fight for control over food security between corporations and farmers now lies.

Although it seems important to demonstrate that the science and alleged benefits of GM crops are untrue we shouldn't have to invest a whole lot of money to show that GM crops don't cause harm. There is enough evidence to show that they do not increase yield consistently, that they are a serious threat to biodiversity, increase the use of chemicals over time and do not benefit consumers or small farm holdings.

Would we invest a lot of effort to counter claims by oil companies such as Exxon who have poured money into research to show that global warming is not taking place? We have enough work to do mitigating and adapting to climate change. Similarly, we need to focus on the challenge at hand-food security in an uncertain future. And we can do that without GM plants by using proven agricultural practices and other innovations that improve food security.

Sujatha Byravan06 November 2009

Dr Sujatha Byravan writes on Science and Technology Policy. She is based in Chennai.