13 Genetically Modified Crops

Dr. Sunil Mittal

1. Introduction

2. Definition and Classification

3. History of Genetic modification and GM crops

4. Global Scenario of GM crops

5. GM crops in India: Research and Development and Regulations

6. Regulatory Framework for GM plants/crops in India

7. Benefits of GM crops

8. Limitations/Potential risks of GM crops

9. Concluding remarks

1.Introduction

The human population has increased very rapidly in the 20th and 21st century. This has increased the food demand at large scale. Since agriculture is the primary source of food, the crop improvement has become necessary to meet the food demands of ever increasing population. Many conventional techniques like mutagenesis, hybridization and polyploidy have been used by plant breeders to improve the crop production and quality. However these techniques are less effective, time consuming and desired results may not be obtained even after many generations. Therefore new techniques involving biological tools such as genetic engineering are gaining popularity. In this technique desired characters from other plants or any other organism are transferred in to the host (plant of interest) via genes. These are called genetically modified plants or crops. Genetic engineering tools are elegant as they merge numerous bioscience techniques. The most dominating tool of genetic engineering is recombinant DNA technology (rDNA). This technology simplifies the insertion of gene of interest into target cell irrespective of the phenomena whether they are having genetic similarity or not. However, this technology is not applicable everywhere. There are some products that have been developed using gene silencing method. For example, tearless onion and decaffeinated coffee. All genetically modified plants, animals and bacteria come under a common term that is known as genetically modified organisms. There are number of genetically engineered products that have been commercialized throughout the world in the field of agriculture, environment, medicine etc. At present, these genetically engineered crops and products are under strict rules and regulations so as to optimize their beneficial effects such as biosafety, bioefficacy, and environmental protection. On the other hand, the conventionally produced crops and their products do not undergo such kind of evaluation. Even the crops that are produced via artificial hybridization and induced mutations do not pass through these strict rules and regulations, despite of the fact that these can produce undesirable effects on human beings and the environment. Those crops or plants that contain foreign gene are termed as transgenic or genetically engineered plants. The broader term that has been used for transgenics and genetically engineered crops is “genetically modified organisms (GMOs)”. The present chapter summarizes the classification, history, global scenario, GM crops in India and its regulations.

2.Definition and Classification

Genetically modified organism (GMO), are those organisms that have been genetically engineered in the laboratory so that expression of desired physiological traits or the production of desired biological products can be favored (Encyclopedia Britannica).

Or

Genetically modified organism (GMO)’ means an organism, with the exception of human beings, in which the genetic material has been altered in a way that does not occur naturally by mating and/or natural recombination (EU Directive 2001/18/EC, article 2 and article 3).

Or

Microorganisms, plants and animals in which the DNA has been altered by means of gene or cell technology (Norwegian Gene Technology Act, Section 4).

The genetically modified (GM) crops have been categorized into three generations.

1.First Generation includes those GM crops that have been grown from the seeds developed via biotechnological tools. These seeds possess some peculiar properties such as resistant to various herbicides, pests and pathogens.

Examples: insect resistant maize and potato, herbicide resistant potato, herbicide resistant soybean.

2.Second generation includes those GM crops that display increased levels of healthy fats, proteins, flavor, micronutrients and carbohydrates.

Examples: rice (increased beta carotene), potatoes (calcium content), soybean (improved amino acid composition), tomatoes (high level of carotenoids), maize (increased vitamin C).

3.Third generation includes those GM crops that have traits for tolerance against abiotic stress factors such as thermal and drought resistance, and salinity. The GM crops included in third generation can also have traits that provide health profit.

Example: Recombinant antithrombin is the first human drug that is having biological origin from goat’s milk.

3.History of Genetic modification and GM crops: from early breeding to present biotechnology

The history of genetic modification began with Darwin’s theory of natural selection. Some key points regarding to the history of genetic modification is enlisted in Table 1:

4. Global Scenario of GM crops

Commercialization of genetically modified crops was started in 1996 on an area of 1.75 million hectares. Increase in the area and production of genetically modified crops represents the good adoption of these crops throughout the world by small and large farmers during the time period of 20 years (1996- 2016) (Table 2). In these 20 years, 2 billion hectares have been covered under genetically modified crops which comprise of 1 billion hectares of genetically modified soybean, 0.6 billion hectares of genetically modified maize, 0.3 and 0.1 billion hectares by genetically modified cotton and canola, respectively. It has been estimated that these genetically modified products provide food and shelter to 7.4 billion people. It is predicted that it would be up to 9.9 billion in 2050 and 12.3 billion in 2100. Top three countries USA, Brazil and Argentina have 39%, 27% and 13 % area respectively, under genetically modified crops (Table 3).

Soybean, cotton, canola and maize have been reported to be the most planted biotech/GM crops in 2016. Biotech soybean occupied 91.4 million hectare area and the area occupied was 78% of the worldwide soybean production. Thirteen percent increase in adoption of biotech maize was recorded from 2015. Global scenario showed that biotech maize occupied 60.6 million hectares. The area occupied by GM maize was 64% of the worldwide maize production. However, plantation of biotech cotton decreased by 7% from 2015. The area under biotech canola increased by 1% i.e., from 8.5 million hectares to 8.6 million hectares during 2016.

Global value of biotech/GM crops

During the year 2016, the market value of biotech/GM crops was reported to be US$15.8 billion throughout the world. However, the market value in 2015 was US$15.3 billion. There was a difference of three percent in the market value of GM crops for the year 2015 and 2016.

Source: International Service for the Acquisition of Agri-Biotech Applications (ISAAA, 2016)

List of commercially approved GM crops

There are some crops that have been modified genetically and approved by GM approval database (Table 4). T Table 4 enlists the names of some approved GM crops.

5.GM crops in India: Research and Development and Regulations

It is an unfortunate thing that the business of GM crops in India is captured by top multinational companies. Moreover, there are certain reports which suggest that the use of GM crops may head to mono-culturing. If this happens, the biodiversity can get devastated and can serve as bio-weapon for the target nation. Trials are going on with GM crops in India, but still the farmers have to rely on the traditional practices and knowledge of farming.

Case study of Bt cotton in India

In 2002, Monsanto and Mahyco (Maharashtra Hybrid Seeds Corporation) got clearance from Genetic Engineering Approval Committee for the plantation of Bt cotton in central and southern India. Aproximately, 55,000 farmers decided that they will grow Bt cotton. During the initial months, the crop grew very fast and farmers were happy. Moreover, there was no attack of worms on the leaves. Suddenly, the Bt cotton growth and new buds production was stopped in the fourth month. At the peak stage, the crop displayed the symptoms of wilting, leaf drooping and shedding, and the plants dried up. Moreover, there was heavy infestation of bollworm. This resulted in 79% and 100% crop loss in Andhra Pradesh and Madhya Pradesh, respectively. The cotton crop was totally destroyed by bollworm in Gujarat. The farmers suffered heavy losses and around 200 farmers committed suicide. Loss of twenty million Euros was recorded across the country due to failure of Bt cotton in one cropping season. According to the law, if the company is held responsible for variety failure, it will provide reimbursement to the farmers.

Despite of rules and regulations, Monsanto didn’t provide any sort of compensation. In contrast, Monsanto-Mahyco provided Indian government with the data that showed that plantation of Bt cotton was great success. Decreased production of Bt cotton produced havoc in Indian economy.

6.Regulatory Framework for GM plants/crops in India

Biosafety concern has led to development of rules, regulations, guidelines, and policies for safe use, handling, and research and testing of the GM plants and products. In India, three main ministries deal with biotechnological applications in agriculture.

1. Ministry of Agriculture
2. Ministry of Environment, Forests and Climate Change (MoEFCC)
3. Department of Biotechnology (DBT), Ministry of Science and Technology (MST).

The rules and regulations amended by these three ministries cover wide area of GMOs and products across the country. There are six authorized bodies that are associated with the framing of regulatory network are as follow:

• Recombinant DNA Committee (RDAC)
• Review Committee on Genetic Manipulation (RCGM)
• Genetic Engineering Approval Committee (GEAC)
• Institutional Biosafety Committees (IBSC)
• State Biosafety Coordination Committee (SBCC)
• District Level Committees (DLC)

1) Recombinant DNA Committee (RDAC): This committee comes under DBT and This committee recommends safe rules and regulations regarding the research of recombinants, their uses and applications.

 2) Review Committee on Genetic Manipulation (RCGM): This committee includes DBT, Indian Council of Medical Research (ICMR), Indian Council of Agricultural Research (ICAR), and Council of Scientific and Industrial Research (CSIR). Its function is to supervise safety related issues of those projects that involve GMOs. Keeping in view the environmental safety, it frames down certain procedures with respect to the production, import and sale of GMOs. This committee can also form sub groups that can assist RCGM in the preparation of new guidelines.

3) Genetic Engineering Appraisal Committee (GEAC): Earlier, this committee was known as Genetic Engineering Approval Committee. This committee comes under MoEFCC. This committee is concerned with the mass release of GMOs and their commercialization.

4) Institutional Biosafety Committees (IBSC): This committee comes under DBT and It aims at the preparation of site-specific strategies for the use of GMOs. Any institute that is handling microorganisms or GMOs must constitute this committee. The committee will include

• Head of the institute
• Scientists working with rDNA
• Medical expert
• Nominee from DBT

 5) State Biosafety Coordination Committee (SBCC): This committee comes into action when the safety and control measures are violated while handling GMOs. Its main function is to inspect, examine and take disciplinary action in case of violation of safety measures. It acts as nodal agency for the damage assessment and to take control measures.

 6) District Level Committees (DLC): This committee works under the supervision of district collector. Its main function is to monitor the installation of those safety rules that are employed in the use of GMOs.

In short, one can conclude that RDAC performs the advisory function whereas IBSC, RCGM, and GEAC perform regulatory function. SBCC and DLC perform the process of monitoring.

Recombinant DNA Guidelines

Recombinant DNA Guidelines, 1990: During the advancement of biotechnology sector in various institutes and industries, recombinant DNA guidelines were formulated by Department of Biotechnology in1990 and further revised in1994. These revised guidelines were regarding the research and development of GMOs, transgenic plant, animals and effect of their products on environment.

Revised Guidelines for Research in Transgenic Plants: DBT brought separate new guidelines for carrying research in transgenic plants during 1998. These guidelines include the guidelines for toxic and allergenic properties of transgenic plants, plant parts like seed and fruit. Also provide the information regarding the import and export of GMOs for research purpose.

Seed Policy, 2002: This policy deals with the varieties of transgenic plants. According to this policy, GM crops will be tested under the Environmental Protection Act (EPA), 1986 for the biosafety and environment. GM plants are imported for research purpose only through National Bureau of Plant Genetic Resources as per rules of 1986. GM crops are monitored for 2 seasons under coordinated project trials of ICAR. After this, environment and Biosafety clearance seeds are released for commercially use and monitored for 3-5 years by Ministry of Agriculture and State Departments of Agriculture.

The Food Safety and Standards Act, 2006: Ministry of Food Processing Industries introduced Food Safety and Standards Act, 2006. It includes laws related to food and food safety and standards authority of India which provide scientific standards for food products and maintain their manufacturing, storage, distribution, sale and safe import and export of food products. Food Authority also regulates the limits of food additives, pesticide contaminants, heavy metals concentrations, mycotoxins and many more active substances.

Plant Quarantine Order, 2003: This order came into force on 1st April, 2004. It deals with permission of imported transgenic plants seeds. Permission of imported transgenic seeds is essential to detect the impacts of seeds on environment and agriculture of any nation. National Bureau of Plant Genetic Resources (NBPGR) act as Competent Authority that gives import permit for the transgenic seeds to people and private sector for research purposes after getting permission from DBT and MoEF under 1989 rules.

Regulation for Import of GM Products under Foreign Trade Policy: Ministry of Commerce and Director General of Foreign Trade formulated the new regulation for importing of GM products. This policy deals with the importation of GM plants, products and living modified organisms and new conditions were also formulated.

National Environment Policy, 2006: This policy states about the new processes for the living modified organisms and information regarding them like health, economic, environment effect. This policy mainly focuses on the environment awareness, information and education. It also includes suggestions for mainstreaming scientifically valid content for environment in curriculum of formal education in all levels.

7.Benefits of GM crops

a) Insect Resistance: Genetic engineering has been used to make insect resistant plants. It was achieved by the insertion of Bt gene into host plant. This gene confers resistance against insects due to the production of toxins. These toxins bind to the gut of insects upon ingestion and eventually get killed. Such type of genetic modification makes the process of crop production less expensive and manageable.

 b) Herbicide resistance: Crops such as corn, soybean and cotton have been developed via genetic modification. These crops possess a particular trait of herbicide resistance. Since these crops are already resistant to herbicides, therefore there is no need of herbicide application. Herbicide resistant crops require less tilling and also prevent the topmost soil from erosion.

 c) Disease resistance: Genetic engineering has also gifted some disease resistant plants. For example, papaya, tomatoes, potatoes etc.

 d) Enhancements in nutritional quality: Crops like Golden rice with higher content of vitamin A have been produced by genetic engineering technology. Application of genetic engineering can also be used to amend the carbohydrate and protein content of amino acids. Example of alteration in carbohydrate content includes the production of Amflora (potato variety). Similarly, sweet lupine presents a good example of modification in protein content i.e., enrichment in methionine.

 e) Up-gradation of food processing: Genetic modification can also be used to make food processing smoother. Flavr Savr produced by Calgene (US company) is the best example of this technology. The tomato produced by Calgene shows delayed ripening and longer shelf life. Similarly, gene editing has been used to alter the composition in potato bulbs. As a result, the potatoes exhibit striking appearance and brightness.

f) Production of edible vaccines

The technique of genetic engineering has made it possible that bacterial and viral antigens can be expressed in edible part of plant cells. Therefore, transgenic crops/foods may serve as oral vaccines. These vaccines have the capacity to induce the production of antibodies and stimulate the immune system.

8.Limitations/Potential risks of GM crops

 a) Health risks: If GM crops have beneficial effects, they also have certain negative effects which mark their limits. GM crops have great potential to induce allergic reactions. Digestive stability of these crops/foods should be examined to prevent allergenicity. 

Other health risks associated with GM crops is toxicity and genetic hazards. The potential sources of these risks include

1. Gene of insertion and its expressed protein
2. Pleiotropic effects of proteins
3. Disruption of existing/natural genes in the modified organism

Example: Starlink variety of maize was genetically modified with gene from Bacillus thuringiensis to provide insect resistance. The inserted gene expresses Cry9c protein. This protein possessed pesticidal properties. However, consumption of this variety induced strong allergic reaction in consumers.

Example: soybean production with higher content of methionine. The gene that was responsible for the increased content of methionine was isolated from Brazil nuts. Consequently, the consumers those were sensitive to these nuts, developed allergy after consumption of transgenic soybean.

b) Gene Transfer: Transfer of DNA from GE foods inside human body cells or bacterial cells in gut is also a matter of concern. DNA of the ingested GM food doesn’t undergo complete digestion. As a result, DNA fragments are absorbed by the gut bacteria or somatic cells of the intestine via the process of horizontal gene transfer. Most of the researchers claim that the ingested DNA of GM crop would be digested totally. However, persons suffering from gastrointestinal diseases should be more concerned as it is not clear whether the DNA of GM crop would be fully degraded inside the gut or not.

c) Outcrossing: The process of gene transfer from genetically modified plants to other plant species is known as outcrossing. If GM crops are planted in close proximity of related plants, then there are maximum chances that new traits will be exchanged via pollen.

Similar situation was created in case of Starling variety of maize. Therefore, various strategies were adopted by different countries so as to minimize mixing and to separate GM crops from traditional crops.

d) Enhancement in the content of anti-nutrients: There are certain reports that prove an increase in the levels of anti-nutrients on the insertion of foreign gene. These anti-nutrients create interference with the consumption of nutrients.

Example: Roundup ready soybean.

e) Disruption of food web

Development of insect resistant plants via genetic modification is a boon to the farmers. There would be a drastic reduction in the number of major pests. However, minor pests will increase in number. Consequently, the food web will get disrupted.

9.Opposition and Controversies related to GM crops

1. Scientists cannot conduct autonomous research on seeds. They have to obtain prior permission from Seed Company like Monsanto, DuPont and Sygenta, and patent holder. As a result, scientists get frustrated because of the restrictions imposed on them by industries.
2. Crop scientists are worried about the efficacy of herbicide resistant plants against glyphosate.
3. Since public funds are shrinking day by day, therefore scientists are totally dependent on research grant from funding agencies.
4. A report stated that greater part of GM crops is not developed for poor people of world. However they are used in rich countries for the production of highly processes foods or as biofuels and animal feed.
5. There is a lack of studies that are focused on the safety assessment of GMOs. Moreover, the current safety assessments are insufficient to grab a large amount of the injurious effects of GM crops. In addition to this, risk assessment of GM crops has never been made thoroughly under Indian conditions.
6. Professional and financial conflicts of interest are associated with those studies that are displaying favorable results for GM crops.
7. Several health hazards such as swollen faces, skin itching is associated with Bt crops. Researchers are also studying the reason of infertility and decline in cattle’s milk yield due to consumption of Bt cotton.
8. Impact of Bt cotton has not been studied intensively on soil ecology. Farmers complain of decline in soil productivity after sowing of Bt cotton.

Concluding remarks

The chapter led to the conclusion that GM crops have been grown for the past 20 years. These crops are associated with several beneficial and negative effects. There are certain rules, regulations and guidelines for the handling of GM crops. Lethal effects of GM crops are shown on fertility and gastrointestinal tracts. There should be no restriction on scientists for seed testing prior to any authorization. Monitoring and surveillance of GM foods should be carried out intensely.