Genetic modification: the science behind it
A gene is a code that governs our appearance and characteristics. When a scientist genetically modifies (GM) a plant, s/he inserts a foreign gene in the plant’s own genes. What makes it possible to transfer genes from one species to another is the fact that all genes are created from the same material DNA. Beneficial genes are transferred into plant cells using a soil bacterium, Agrobacterium tumefaciens, which can produce tumour-like growths in plants and has the ability to alter plants’ DNA. For example, when a gene from a bacterium that is resistant to pesticide is inserted into a plant’s gene, the plant will be able to withstand pesticides. Genetic modification does not always involve moving a gene from one organism to another. Sometimes it means changing how a gene works by ‘switching it off’ to stop something from happening. For example, the gene for softening a fruit could be switched off so that although the fruit ripens in the normal way, it will not soften as quickly. This can be useful because it means that damage is minimised during packing and transportation.
In traditional processing, characteristics can only be exchanged between species which are the same or very similar. By genetic modification, however, it is now possible to add a fish gene to a tomato. By this, researchers created a frost-resistant tomato plant by adding an antifreeze gene from a cold-water fish to tomato. However, the research has not made substantive headway.
Source : CAI, Cotton statistics new (No. 40 ) and CICR
GM food experiments and trials in India
India produces Bt cotton, which contains a biological pesticide that kills the common pest bollworm. The approval for the use of Bt cotton has been there from 2002 and since then it has helped make our country the second largest cotton manufacturer in the world. As a result GM seeds account for over 90 per cent of cotton sown in India. However in 2015, GM cotton plants in Punjab and Haryana suffered a whitefly attack resulting in massive losses (Fig 1). This episode has created a sense of negativity towards GM in India. It is generally believed that adopting GM technology would lead to higher crop productivity solving the food problem of a burgeoning India. Currently, a food supply deficit is pushing prices up and India has been forced to import pulses to plug the gap between demand and supply.
In India, experiments have been carried out in GM crops, such as golden rice, which was originally produced in 1982 as an initiative for the Rockefeller Foundation. Beta-carotene gives golden rice its ‘golden’ or ‘yellow’ colouring. White rice, on the other hand, does not contain carotenoids, pro-vitamin A. Golden rice contains the β-carotene which either accumulates in our fatty tissues or is converted into vitamin A. In fact, young children are the most vulnerable to vitamin-related deficiencies. It is approximated that 1 million children die of a vitamin A deficiency each year. One of the main problems with the original form of golden rice was that it did not contain enough vitamin A to reduce the disease risks. Another problem could be low absorption. This problem was rectified when the new Golden Rice 2 was developed in 2005. In 2009, it was found that golden rice was just as beneficial and effective as supplementing with vitamin A (Tang et al 2009).
Greenpeace, a non-governmental environmental organisation vehemently opposes the production and use of golden rice citing that such genetically modified crops would further encourage the induction of more such developments in the future. This may cause the degradation of foods to the point where everything that we eat will be artificial and genetically engineered. In the long run these types of non-natural foods might cause a variety of health problems.
A new form of pigeon pea that is pest-resistant was developed at the International Crops Research Institute for the Semi-Arid Tropics, predicting that it can increase output by 30 per cent. Perhaps the most promising GM crop, developed in Delhi University, is the hybrid mustard that yields 25-30 per cent more than the original seed. The GM mustard seed could be a huge money saver and could lower the country’s dependence on edible oil imports. It is worth mentioning here that in 2014-15 India imported 14.5 million tonnes of edible oil, worth over 10 billion USD.
Though India has resisted GM food production till now, it is suspected that there have been instances of GM food being imported into the country—corn, baby food and breakfast cereal, which have been introduced without adherence to relevant labelling laws. While a Directorate General of Foreign Trade notification in 2013 addressed the issue of labelling by requiring those importing GM food to explicitly mention it in their labels, in the case of home-manufactured products like edible oils, there are chances of GM cottonseed oil being mixed with other edible oil without any labelling. Though no state government in India has permitted commercial cultivation of GM food till now, field trials for 21 GM food crops, including GM vegetables and cereals, have been approved by the government (Venkat, 2016). An agreement to develop Bt brinjal was signed in 2005 between Mahyco-American agricultural biotech giant Monsanto’s Indian Bt cotton partner, and two Indian agricultural universities. However India’s potential propelled Monsanto to also include GM corn in their research. Other companies pursued rice, mustard, peanuts, potatoes and sorghum. Following the study of bio-safety data and field trials by two expert committees, Bt brinjal was cleared for commercialisation by India’s top biotech regulator, the Genetic Engineering Appraisal Committee (GEAC), in 2009. But nothing came of it, due to moratoriums imposed by the then government.
In addition to crops and vegetables as well as oilseeds, experiments are also underway on several species of fish. In fact, such is the desperation that scientists are trying to insert a Bt gene into any crop they can lay their hands on, not knowing whether it is desirable or not. This race for GM experiments could be due to available funding from the biotech companies as well as support from the World Bank, Food and Agriculture Organisation and the Consultative Group on International Agricultural Research.
Source : international service for the acquition of agri- biotech
Impact on environment and health—a major concern
There are too many unintended impacts on environment, health, markets and environment like harming non-target and/or beneficial species in the case of crops with engineered insecticidal properties as well as the development of new strains of resistant pests. In addition, there is a concern that pollen from GM herbicide-resistant crops could reach wild, weedy relatives of the crop and create so called superweeds.
With regard to health, there is no evidence to suggest that GM foods are unsafe. At the same time there are no absolute guarantees either. Unintended health impacts from genetically modified organisms (GMO) include allergens, antibiotic resistance, decreased nutrients, and toxins. The International Agency for Research on Cancer (IARC) classified glyphosate, a herbicide that goes with Monsanto’s Roundup Ready product, as ‘probably carcinogenic’ in 2015. However, food scientists did not agree with the result. According to them, the herbicide ensures that only the weed dies and not the crop itself as the GM food is modified to resist glyphosate.
In a review paper of GMO safety assessment studies, Cuhra (2015) has shown that glyphosate-tolerant GM food plants accumulate glyphosate residues at unexpectedly high levels. Glyphosate is a powerful synthetic antibiotic and blocks mineral absorption. Glyphosate herbicides are endocrine disrupters and mitochondrial toxins and have been linked to birth defects.
Trend in other countries
The US cultivates eight crops using GM technology. Further to that US Regulators last year blessed genetically engineered potatoes, apples and a salmon that grows faster than conventional versions and represented the first biotech animal cleared for human consumption. A list of GM crops allowed worldwide is provided in Figure 2.
There were complaints on pricing and yield regarding Bt cotton resulting in closing down the sales by Monsanto in Indonesia in 2003 (www.lobbywatch.org). With highly critical reports of regulatory mechanism coming in force from independent institutions, the trend in USA was also towards still more tougher regulations compelling biotechnology companies to grow the next generation of GM crops in isolation using artificial lighting and air filtration in order to avoid pollen movement and contamination. In America, opponents launched state-by-state efforts to make GMO-food labelling mandatory. Following the USDA’s 2015 approval of genetically modified apples and potatoes, companies including McDonald’s Corp, and Wendy’s Co. said they did not plan to use them. The European Union unveiled a new opt-out programme in 2015. Ukraine and Russia have also ruled out using GMO seeds. China, which permits some biotech cotton, papaya, sweet peppers and tomatoes, is not expected to approve new GMO crops until the domestic seed industry shows it can compete against western rivals. Nineteen EU countries have stated that they will not allow their agricultural systems to be destroyed by growing harmful GM crops. Thirty eight countries worldwide have officially banned the cultivation of GM crops and only 28 actually grow GM crops.
It is assumed that there will be 1.8 billion Indians by 2050. It is suggested that GM crops could be the only way to feed them all. Farm economists might also join hands for using GM technologies in India. The Indian environmentalists believe GM crops to be toxic and hazardous to human health arguing that the GM being a pretty recent technology, the effects of consumption of the same over generations are not predictable now. At the same time it should be borne in mind that although the industry claims that no humans have been hurt by consuming GMOs, it is necessary to have scientific monitoring of human health effects.
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The authors are Scientists and Former Director from Defence Food Research Laboratory, DRDO, respectively. email@example.com