10 Use of Genetically Modified Organisms in Global Agriculture

M. Laura Rolon

Learning Objectives

At the end of the chapter, students will be able to:

 

  • Summarize the science behind GMOs.
  • Explain the process for regulatory approval of GMOs for use in agriculture.
  • Address the challenges facing GMO acceptance from the consumer’s viewpoint.
  • Debate the opportunities and challenges of applying GMOs in developing economies.

 

 

Definitions

 

There is much ground to cover when discussing the application of biotechnology to agriculture. This chapter uses definitions, acronyms, and biological concepts that you might already know. However, a refresher on the most important terms used throughout this chapter may be helpful.

  • Genetically modified organisms (GMOs), genetically engineered (GE) organisms, recombinant DNA organisms, and transgenic organisms: The World Health Organization defines GMOs as “organisms (i.e., plants, animals or microorganisms) in which the genetic material (DNA) has been altered in a way that does not occur naturally by mating and/or natural recombination.” Other terms commonly used to describe these organisms include genetically engineered (GE) organisms, recombinant DNA organisms, and transgenic organisms. There is a lively discussion in the scientific community about which term is best. In this chapter, we use GMOs, a term used throughout the literature and in policy documents.
  • Trait: A characteristic of an organism is called a trait. Examples of traits in the plant world include height, drought tolerance, and resistance to disease.
  • Genome and genes: The genome of an organism is all the genetic information stored in the DNA of the organism’s cells. Genes are discrete portions of the genome that encode proteins with a specific function in the organism, like the enzymes used for metabolism.
  • Chromosomes and plasmids: Genetic information is stored as long portions of DNA called chromosomes. Some organisms, like bacteria, may have additional genetic information stored as small circular segments that can independently replicate (plasmids).
  • Polymerase chain reaction (PCR): PCR is a laboratory technique used to obtain multiple copies of DNA from a single copy.
  • Homology: If two sequences of DNA or protein from different organisms have similar structures and functions, they are called homologs.

 

Introduction

 Humans have selectively bred plants and animals with the aim of obtaining better-quality varieties for agriculture and livestock production for millennia. When humans started to transition to an agricultural lifestyle around 10,000 B.C.E., they began to domesticate wild varieties of food plants and animals by selecting varieties with optimal traits such as improved yields and pest and disease resistance (Chassy, 2007). In traditional breeding, two individuals of the same species with separate desirable traits are bred to combine their traits into a new hybrid or variety. Similarly, interspecies breeding is when two closely related species are crossed to create an improved hybrid with traits of both species (Kinsbury, 2009). An illuminating example can be found in the evolutionary history of maize (corn) from teosinte. Teosinte is the grass from which the current maize plant evolved. Through a series of hybridization events, teosinte acquired desirable traits, such as larger ears, more seeds per ear, and seeds that do not break away from the plant or shatter as they usually would for dissemination (Hake & Ross-Ibarra, 2015). Breeding techniques always entail modifying plant genomes by crossing parent plants until the offspring exhibit the desired trait. Breeding new plants and animals to obtain a particular trait requires extensive time and resources.

 

The rise of biotechnology (i.e., the technology that allows humans to manipulate the genomes of organisms directly) and its use in agriculture is commonly referred to as the Second Green Revolution. Using molecular biology tools, scientists can modify the genome of an organism by incorporating specific genes from a different (and sometimes unrelated) organism to produce a desired trait. This results in what is known as a genetically modified organism (GMO), genetically engineered (GE) organism, recombinant DNA organism, or transgenic organism. The development of GMOs extends beyond the production of crops for agriculture. One of the first commercial applications of biotechnology was the insertion of the genes that produce human insulin into a bacterium, resulting in a high-quality and cost-efficient way of manufacturing insulin (previously, humans depended on insulin obtained and purified from hogs).

 

Genetic engineering in the agricultural sector is seen by some as a key technological innovation that can reduce food insecurity and generate crops resistant to the challenges of climate change (Dadgarnejad et al., 2017). Several GMO crops have been developed or are under development with the goal of improving the crops’ disease and pest resistance (i.e., Bt-eggplant, rainbow papaya), improving nutrition (i.e., Golden Rice), and engendering resistance to herbicides (i.e., Roundup Ready). However, there are concerns about the potential risks of the technology, including GMOs’ safety for human consumption, their effects on the environment, the potential for gene transfer, and consumer acceptance.

 

As an introduction to the debate, watch these two TED talks, one in favor and one against using GMOs in agriculture and food production. Keep in mind that while this chapter focuses on plant GMOs, the technology is used in other organisms like bacteria (e.g., for the production of chymosin, the enzyme necessary to produce cheese), yeast, and insects (e.g., for the biological control of pests; Hokanson et al., 2014).

 

 

Additionally, consider watching a debate regarding GMOs’ use in agriculture organized by the nonprofit Intelligence Squared U.S.

 

The Science Behind GMOs

A simplified way to understand how GMOs are developed involves six steps:

  1. Identification of a gene that produces a trait of interest for a crop.
  2. Isolation of the gene and amplification.
  3. Introduction of the gene to host cells.
  4. Tests in controlled environments (i.e., greenhouses and field trials).
  5. Safety testing.
  6. Commercialization.

 

We illustrate the concepts underlying the development of a GMO crop with the example of the insect-resistant Bt-eggplant crop.

 

  1. Identification of a Gene That Produces a Trait of Interest for a Crop

    Eggplants (or brinjal; Solanum melongena) are a horticultural crop of importance for Asian countries such as India, Bangladesh, and Nepal. Eggplants are susceptible to an insect pest called brinjal fruit and shoot borer (Leucinodes orbonalis), a moth that feeds on the plants’ leaves and flowers. The moth can damage the fruit, culminating in a reduced crop yield. In Bangladesh, farmers depend on eggplant production as a source of income (Shelton et al., 2018) and rely heavily on the application of chemical insecticides to control the pest (Prodhan et al., 2018; Shelton et al., 2018). The desired trait to control insects has been found in Bacillus thuringiensis (Bt), a bacterium that can produce endotoxins known as Cry proteins. These endotoxins attack the guts of insects that feed on eggplant cultivars. Cry proteins become soluble in the alkaline environment of the gut of some insects, where they attack the epithelial cells producing pores (Sanchis, 2011). Cry proteins are nontoxic to humans as the human stomach is acidic and will not solubilize the protein. In addition, there is no receptor in the human gut for the alkaline product. Cry proteins have been shown to be effective against some insect pests and nontoxic to other beneficial insects (Prodhan et al., 2018). For more than 60 years, Bt-based insecticides have been used by farms, including organic ones, to manage pests without relying on chemical insecticides (Romeis et al., 2006). Obtaining an eggplant variety that produces Bt proteins by traditional methods is impossible as scientists cannot hybridize between bacteria and plants. However, it is possible to transfer the gene that encodes a Cry protein to the eggplant genome to create a pest-resistant variety and eliminate the need to apply the insecticide to the field. The India-based Maharashtra Hybrid Seed Company (Mahyco) developed the Bt-eggplant (Shelton et al., 2018).

 

Bt-based technology is not limited to eggplants in Bangladesh. Cry proteins have been incorporated into other crops, including maize and cotton (Romeis et al., 2006), to protect them from crop-specific insect pests.

 

  1. Isolation of the Gene and Amplification

After the DNA sequence that encodes for the trait of interest is identified, a high concentration of DNA by amplification can be produced using the polymerase chain reaction (PCR) technique. The PCR technique allows for the isolation and amplification of a specific gene sequence. The isolated sequence is then transferred into a plasmid before being introduced into plant cells.

 

  1. Introduction of the Gene to Host Cells

There are two main ways to introduce a gene into the genome of a plant: using bacteria to transfer the desired DNA into the host cells or coating metal particles with DNA and firing the particles through the cell wall (Ishii & Araki, 2016; Zhang et al., 2016). In the first method, the bacterium Agrobacterium tumefaciens is used for DNA transfer. This soil bacterium is known as a plant pest, causing the formation of galls in trees with open wounds. Agrobacterium’s genome consists of a circular chromosome, two small plasmids, and one large plasmid. The large plasmid contains the machinery Agrobacterium uses to infect plant cells and transfer its DNA to induce tumors in the plant. When scientists discovered this mechanism, they began to use Agrobacterium as the vehicle to inject a piece of DNA into plant cells. The tumor-inducing plasmid was modified to remove the genes that produce galls. Agrobacterium was subsequently modified to incorporate the genes containing the desired trait, the genetic mechanisms necessary to express the trait (i.e., promoters), and a selective marker to differentiate the modified plants. Today, plant cells are exposed to the modified Agrobacterium, which employs its invasion mechanism to inject DNA into the plant cell, incorporating it into the plant genome. In an alternative technique, the desired DNA sequence is coated on metal beads and fired using a cellular gun into the cell. (Yes, this is what it sounds like, but on a molecular level.) The metal beads can pierce through the plant cell wall, and the DNA then integrates into the genome of the plant cells. See this publication for more information on this process.

 

After the GMO eggplant was developed, the technology was transferred to the Bangladesh Agricultural Research Institute through a public–private partnership for incorporation into local varieties of eggplant, field testing, and distribution (Shelton et al., 2018).

 

  1. Tests in Controlled Environments (Laboratories, Greenhouses, and Field Trials)

Several tests are conducted on GMO plants under controlled conditions to verify the gene’s successful insertion, the protein’s production, and its effectiveness. The plant cells are initially grown in a laboratory to isolate those cells that have successfully incorporated the gene and now express the trait. This is achieved using a selection marker added to the plasmid, such as antibiotic resistance or sugar consumption. Next, the plants are cultivated in a greenhouse to evaluate the production of the protein of interest (e.g., the expression of Cry proteins) under ideal growth conditions. GMO and non-GMO plants (i.e., the experimental controls) are exposed to the pest to verify that the protein production results in the desired effect. The effect of the protein on other nontarget species (i.e., other insects) is also evaluated. Finally, the crops are tested in an open field to observe the effects of the environment (e.g., soil, water, other plants, insects) on the crops given the expression of the new trait. In the Bt-eggplant case, tests were used to determine the effectiveness of the new variety compared to the non-GMO crop. Scientists also measured the effect of the new variety on other beneficial insects important to the agroecosystem (Prodhan et al., 2018).

 

  1. Safety Testing 

Before widespread use, additional tests are necessary to verify that GMO crops are safe to be released into the environment. The number of safety tests depends on each country’s legislation. Environmental impact studies of GMOs are needed to establish the effect of a genomic modification on the environment. This includes the effect of the modification on soils and water, any possible transfer of inserted DNA into other species, and whether the target or nontarget organisms develop resistance to the modification (Zhang et al., 2016). These tests are conducted by comparing a GMO crop to a non-GMO variant. When Bt-eggplants were tested, two fields were planted: one with eggplants expressing the Bt gene and the other without the gene.

 

Finally, before a GMO crop is approved for release, it is tested and evaluated for any risks associated with human consumption. We discuss safety regulations related to human health in the next section. GMOs need to be approved by governmental agencies before the seeds can be mass-produced and commercialized. The specific approval process depends on each country’s particular agriculture biotechnology legislation. In Bangladesh, the regulatory system requires the approval of each variety of GMO produced independently (Shelton et al., 2018).

 

  1. Commercialization

This step is dependent on who develops the GMO crop variety. If for-profit corporations develop crops, they seek a patent for their products and sell the seeds through established seed companies. Patents allow the inventors and developers of the GMO variants to have exclusive control of their products for a limited time. This prevents competitors from using the new crops initially; patents encourage research and development while eventually making the technology part of the public domain. The purchase of commercial seeds may require farmers to sign a contract in which they agree not to save seeds for the following season and to remove GMO plants that may grow outside of their fields. These contracts are enforced by the companies that developed and commercialized the GMO seeds, and infractions may result in fines or lawsuits. Other GMO projects are developed by publicly funded research institutes or public–private consortia, providing GMO seeds to farmers at little to no cost.

 

The aforementioned public institute, the Bangladesh Agriculture Research Institute, deployed the Bt-eggplant in Bangladesh. The institute first distributed its seedlings to 20 farmers in January 2014 and continued distributing the seeds in increasing amounts over the following years, reaching 27,012 farmers in 2018 (Shelton et al., 2018). The institute continues to support farmers who adopt the technology by providing them with workshops and technical assistance while monitoring the development of pests with resistance to the Bt-proteins (Shelton et al., 2018).

 

 

Application of GMOs Around the World

According to the International Service for the Acquisition of Agri-biotech Applications (ISAAA; 2017), in 2017 there were 189.8 million hectares across 24 countries devoted to producing GMO crops. The 10 most prominent producers of GMO crops by area of production are the United States (40%), Brazil (26%), Argentina (12%), Canada (7%), India (6%), Paraguay (2%), Pakistan (2%), China (1%), South Africa (1%), and Bolivia (1%). Of the area devoted to GMO crop production, approximately 50% is planted with soybeans; 31%, maize; 13%, cotton; 5%, canola; and < 1% for all other biotech crops.

 

Herbicide tolerance has historically been the most prominent trait of GMO crops planted worldwide. The most widely used GMO crops are Roundup Ready crops, initially sold by Monsanto (now Bayer). There are other companies that sell similar products under different brands. These GMO crops have an introduced gene that encodes a protein that provides resistance to the glyphosate herbicide. After planting Roundup Ready seeds, farmers can spray their fields with glyphosate (Roundup) to kill weeds while their crops remain unaffected. Other traits commonly incorporated into food crops are disease-resistant genes.

 

An example is the virus-resistant papaya (also known as the rainbow papaya) cultivated on the islands of Hawaii. There is a trend among scientists of stacking traits to make GMO crops with combined resistance to herbicides, insects, and disease (International Service for the Acquisition of Agri-biotech Applications [ISAAA], 2017). The ISAAA has developed a comprehensive database of GMO crops, their traits, and commercial names approved for commercialization/planting and importation in any country.

 

Despite the potential of GMOs to increase agricultural productivity and improve food security, the application of the technology in Africa has been limited to a few countries, including South Africa and Sudan (Adenle et al., 2013). Development of GMO staple crops for Africa, such as disease-resistant banana, cassava, sweet potato, and potato; insect-resistant cowpea; biofortified sorghum; and drought-tolerant corn are currently in greenhouse and field-trial phases in some African countries (Adenle et al., 2013; ISAAA, 2017). The main limitation to the introduction of GMOs into Africa is the availability of effective biosafety regulations and the rigorous (but expensive) safety verifications needed for approval (Paarlberg, 2010). Furthermore, there are political and economic implications related to the international trade of crops with Europe, resulting in additional regulations to trade with the European Union (see Section 4.4.2; Paarlberg, 2010).

 

Safety of GMO Crops: Are GMOs Safe to Be Consumed by Humans?

 The first step to assess the safety of GMO crops is to conduct a risk assessment. For this purpose, it is necessary to identify the hazards (i.e., things that can cause harm or damage) that may arise from the consumption of GMO food, the probability that these events will occur, the outcome of each particular hazard, and the severity of the hazard (Varzakas et al., 2007). Risk assessment of GMO crops considers three main aspects: the effects of the physiology of the crops on specific hazards, the nutritional quality of the final food, and any potential health hazards upon consumption. Risk assessment in the food system can only be evaluated in relative terms (Chassy, 2007). Thus, GMO crops are always compared to their non-GMO counterparts that have been cultivated and consumed by humans for a long time without significant adverse effects (Food and Agriculture Organization [FAO]/World Health Organization [WHO], 2000). This comparison is known as “substantial equivalence.”

 

The toxicity of a GMO crop is determined by first evaluating the concentration of known toxins naturally produced by the plant. When insufficient information is available to conduct a thorough risk assessment, animal models may be used to determine the potential toxicological effects of the food product (FAO/WHO, 2000). If needed, sub-chronic studies are conducted for 90 days to assess the safety of the new product under repeated consumption. If an unexpected outcome occurs, further testing might be required to determine the cause (FAO/WHO, 2000).

 

Nutritional studies are conducted to verify that the added gene does not modify the nutritional quality of the food. These tests are intended to provide a complete nutritional picture of the GMO food and compare it to its non-GMO counterpart. Additionally, the nutritional quality of the final food product is evaluated by applying all the processes and cooking techniques consumers will use before consumption.

 

The introduction of new proteins into a crop may result in allergic reactions in some individuals. To determine if a food crop can produce an allergenic effect, the proteins produced by the inserted gene are first assessed by their origin (i.e., whether they came from a known allergenic source). Then the protein sequence and structure are compared to known allergens to identify any homologies (i.e., the similarity of the protein to others of known allergenicity). If needed, tests are conducted with blood from allergic persons to verify a positive reaction in vitro. To date, GMO food consumption has shown no adverse effects on humans (Tsatsakis et al., 2017; Valentinov et al., 2019; Yang & Chen, 2016).

 

Implications of GMOs in Policy

The introduction of GMOs to any country, their release in the field, and their control depend on the regulations and policies established by each nation. Internationally, the Cartagena Protocol on Biosafety signed on May 16, 2000, in Montreal and in effect since 2003 seeks to protect biological diversity from the potential risks of living GMOs (Dubock, 2014). The Cartagena Protocol is the main source of information for countries looking to import GMO products (Dadgarnejad et al., 2017). Other international organizations providing input and information include the Organisation for Economic Cooperation and Development, World Health Organization, Food and Agriculture Organization, European Food Safety Agency, and Codex Alimentarius Commission (Dadgarnejad et al., 2017). In the following sections, we look at two different approaches to policymaking regarding GMOs: process-based (as applied in the European Union) and product-based (as applied in the United States). These distinct approaches to the regulation of GMOs have impacted the legislation of other countries and the adoption of the technology worldwide.

 

Regulatory Situation in the European Union

The European Union has “process-based” legislation, which means that the use of genetic engineering to create a new crop results in a regulatory approval process that is more stringent than that which is applied to non-GMO crops (Sandin et al., 2021). New laws, institutions, and procedures had to be created to regulate approval for the production, import, and consumption of GMOs within the European Union (Paarlberg, 2010). Before any GMO product is approved, the product must undergo an extensive risk assessment conducted by the European Food Safety Authority. Some member states also require approval from their ethics committee (Sandin et al., 2021) before the GMO can be introduced or even imported into the country. The European Union follows a “precautionary approach” in which approval can be denied if a hypothetical risk due to the use of the technology has not been sufficiently tested (Paarlberg, 2010). Furthermore, to provide transparency, European legislation requires a special label for all food products that include a GMO ingredient (Paarlberg, 2010; Sandin et al., 2021).

 

Regulatory Situation in the USA

The United States follows “product-based” legislation: the traits of each product determine the legislation that applies (Sandin et al., 2021; Yang & Chen, 2016). In 1988, the U.S. National Research Council decided that the final product, not the process by which it was made, should be the focus of environmental impact and human health risk assessments (Dadgarnejad et al., 2017). In the United States, three governmental agencies are responsible for overseeing biotechnology-derived food products: the Environmental Protection Agency (EPA), Department of Agriculture Animal and Plant Health Inspection Service (USDA-APHIS), and Food and Drug Administration (FDA). Each agency regulates a specific aspect of GMOs: the EPA determines whether pesticides incorporated into crops through biotechnology are safe for human and animal consumption; the USDA-APHIS assesses whether the GMO can become a pest risk to other plants; and the FDA evaluates the final food product’s safety (Yang & Chen, 2016). Following the “substantial equivalence” principle, most GMO crops are considered equivalent to non-GMO crops and do not require pre-market approval (Yang & Chen, 2016). Nonetheless, there is a voluntary food safety assessment by the FDA that most GMO crops go through before commercialization (Yang & Chen, 2016). The United States does not require food manufacturers to inform consumers of the use of GMO-derived ingredients in their products.

 

Social Implications

 The introduction of biotechnology into agriculture has resulted in a complex scientific and political debate that involves different stakeholders throughout the food supply chain: ecologists, environmentalists, politicians, activists in nongovernmental organizations, and consumers (Tsatsakis et al., 2017; Valentinov et al., 2019). The media plays a vital role in distributing information to consumers and amplifying the voices on both sides of the GMO debate, whether regarding GMOs’ environmental impact or their long-term safety (Yang & Chen, 2016). In this section, we focus on two critical aspects of the social implications of biotechnology in agriculture: consumer acceptance and labeling of GMOs and the anti-GMO movement.

 

Consumer Acceptance and Labeling

The first few generations of GMOs aimed to improve the production of food crops by the incorporation of herbicide-, insecticide- and disease-resistance traits that would directly benefit farmers. These modifications are invisible to consumers and may not be perceived as adding value to the final food. Thus, in the initial days of GMO production, communication of the benefits of GMO technology was targeted directly at farmers but not consumers. During this time, there was an escalation in the public debate on the risks and benefits of purchasing and consuming GMO-derived foods. There are four identified sources of fear for consumers: a lack of clear scientific communication regarding the technology’s capability; inconsistent labeling of GMO-derived foods; ethical concerns regarding the genetic manipulation of organisms; and a sense that the safety evaluation of the products is inadequate (Zhang et al., 2016). Public trust, or the lack thereof, in the companies and organizations that develop and commercialize GMO seeds also plays a major role in consumer acceptance. To address consumer concerns and increase transparency, some countries have adopted voluntary or mandatory labeling requirements for food products containing GMO ingredients (Ishii & Araki, 2016). The development of new GMO crops that directly benefit the consumer, such as biofortified foods, will require addressing the ingrained concerns of consumers regarding the consumption of GMOs.

 

The Anti-GMO Movement

The anti-GMO movement, primarily led by nongovernmental organizations such as Greenpeace, Friends of the Earth, and the European Consumer Organization, advocates eliminating GMOs from agriculture. Anti-GMO organizations state that the technology is harmful to humans and the environment, that it benefits corporations at the expense of farmers and consumers, and that research on the long-term effects of the consumption of GMOs is inconclusive (Valentinov et al., 2019). Opponents of GMOs do not believe that GMO technology can address food security issues or that the need to increase the food supply justifies its use (Yang & Chen, 2016). There is concern among activists that there may be unknown consequences of modifying an organism’s genome by adding DNA from unrelated organisms (Yang & Chen, 2016). Additionally, activists worry that the availability of the technology will exacerbate income and access inequality between those farmers who choose to adopt GMOs and those who continue to use traditional techniques (Yang & Chen, 2016). Furthermore, activists are concerned about the environmental impacts of increased resistance to new traits, preservation of genetic biodiversity, and ethical issues related to the human manipulation of living organisms (often referred to by activists as “creating unnatural organisms”). Protests against GMOs have been amplified by the media’s use of terms like “Frankenfoods” to provoke fear among the public (Roberts, 2018). Over the years, activists have conducted multiple demonstrations against biotechnology seed companies, lobbied local legislatures, and destroyed GMO crops in fields where safety trials were being conducted. For example, activists destroyed GMO wheat in field trials conducted by the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Australia in July 2011 and research fields of Golden Rice in the Philippines in August 2013 (Zhang et al., 2016). The anti-GMO movement frequently uses scientific studies to show the alleged side effects of the technology. Often, these claims come from studies that are later retracted, or have already been retracted, by the scientific community due to a lack of scientific merit or other problems with the experimental design (Ishii & Araki, 2016). To date, there have been no reported adverse effects of the consumption of GMO foods in humans. In fact, compared to conventional crops, GMOs use lesser amounts of toxic pesticides (Tsatsakis et al., 2017; Valentinov et al., 2019; Yang & Chen, 2016). Nonetheless, activism against GMOs in agriculture has impacted legislation and policy throughout the world (Valentinov et al., 2019).

 

 

Use of GMOs for Delivering Micronutrients: The Case of Golden Rice

Micronutrients such as vitamins and minerals are essential for human life. Beta-carotene, an orange-yellow pigment found in plants like carrots, is a nutrient necessary for the human body to synthesize vitamin A. Deficiencies of vitamin A may result in blindness, especially among young children. Rice is a staple crop in Asia and the primary source of calories in the region (Dubock, 2017). Rice cannot store beta-carotenes in the endosperm of the grain (the edible part). To provide an additional source of pro-vitamin A to vulnerable populations that consume rice as their main source of calories, since 2006 the International Rice Research Institute (IRRI) has been working on the development of Golden Rice. This genetically modified rice can produce and store beta-carotene in the endosperm, thus giving the rice its golden color.

 

The first proof-of-concept in the development of Golden Rice was obtained in 2000 when Ingo Potrykus and Peter Beyer modified the rice genome to introduce the biosynthetic pathway of beta-carotenes. They added the genes that code for phytoene synthase from daffodil and phytoene desaturase from a bacterium (Ye et al., 2000). The inventors donated the license to the Golden Rice technology with the humanitarian intention of improving the nutrition of communities with a high incidence of vitamin A deficiency. The terms of the license included provisions to ensure farmers would be free to grow, sell, save, and replant the seeds of Golden Rice and that other transgenic traits could be added to address other nutritional deficits (Dubock, 2017). In 2006, the IRRI acquired the second-generation Golden Rice (GR2). The gene that encodes phytoene synthase was replaced with a version that comes from maize, coupled with phytoene desaturase from a common soil bacterium (Paine et al., 2005). Further testing resulted in the selection of the GR2E event, which had been bred into traditional tropical varieties of rice grown in the Philippines and Bangladesh. The beta-carotene produced in the Golden Rice endosperm is sufficient to provide 30–50% of the estimated average requirement (EAR) for a range of vulnerable demographics, including young children and pregnant and lactating women.

 

The safety of Golden Rice was evaluated following international guidelines for transgenic products. These tests sought to verify that Golden Rice grows in a manner similar to its non-GMO counterpart. The tests also examined the new proteins produced by the GMO rice after each step of processing, cooking, and digesting the grain. Toxicology and allergenicity were investigated by comparing the enzymes introduced into the rice genome with known toxins and allergens. An external organization conducted an animal model study to determine the toxicity of the additional enzymes produced. The study showed that a small amount of the protein remains in the grain after processing and is then digested in the gut. Extensive testing using animal models showed no adverse effects.

 

Currently, Golden Rice is undergoing the process of regulatory approval for release in the Philippines and Bangladesh. The United States, Canada, and New Zealand have approved Golden Rice and deemed it as safe as non-GMO rice, the only difference being the amount of beta-carotene present in the grain.

 

Deployment to farmers in Bangladesh and the Philippines will begin once all the regulatory approvals are obtained in each country. The IRRI will transfer the technology to existing seed supply chains, whose members will sell the GMO seeds to farmers at the same price as that of non-GMO seeds with the provision that the farmers must then sell the GMO rice at the same price as that of non-GMO white rice. This strategy will ensure that consumers can obtain the additional nutritional benefit of Golden Rice without having to pay a premium. Farmers will be provided with training, stewardship, and civic guidelines to communicate the differences between Golden Rice and non-GMO rice and how to avoid mixing up the two (though the color is a telling sign of the presence of Golden Rice). Once regulatory approvals are obtained, the product may be deployed in other regions that use rice as a staple crop and whose populations have a high prevalence of vitamin A deficiency.

 

While there are humanitarian intentions behind the development of Golden Rice, the anti-GMO movement has attacked the project, seeking to delay the rice’s approval for commercialization. As previously mentioned, in 2013 trial fields of Golden Rice in the Philippines were destroyed by activists. Despite the adverse effects of this anti-GMO propaganda, the IRRI has encouraged public participation and has developed an extensive communication campaign to promote the benefits of Golden Rice, generate transparency regarding the science of GMOs, and demonstrate how Golden Rice will benefit communities with vitamin A deficiency.

 

Golden Rice is the first biofortified food made possible with the use of biotechnology. Given that deficiencies in zinc and iron commonly co-occur with vitamin A deficiency, the IRRI is currently developing new rice varieties through biotechnology to provide additional nutritional benefits. New rice varieties with improved levels of iron and zinc are in development, as are other varieties of Golden Rice in which high iron and zinc genes have been added to deliver a nutrient-rich product to populations in need.

 

 

Conclusion

 When approaching controversial topics, staying informed and critically evaluating all available information is essential. The use of biotechnology could greatly benefit agriculture by increasing agricultural output, decreasing the use of chemicals, providing essential nutrients to people in need, and alleviating some of the challenges imposed by climate change. However, the concerns raised by activists should be addressed. These include the social issues related to the increased concentration of power among seed companies and income and access inequality for smallholder farmers.

 

For 20 years, humans, especially those in the United States, have been consuming foods made from GMOs. To date, there have been no reported negative effects of GMOs on human health or the environment; in fact, there is broad scientific consensus regarding the safety of GMOs (Tsatsakis et al., 2017). However, there have been reports of resistance emerging in pests exposed to GMOs, such as herbicide resistance in weeds and insecticide resistance in insects. These developments should be continuously monitored.

 

Another important takeaway from the GMO debate is how to communicate technological innovations to consumers fully without resorting to fear-based campaigns. The media has played a crucial role in amplifying the various perspectives; thus, it remains essential for scientists to provide guidance and scientific resources in a manner that reaches the general population.

 

No one technology is a magic bullet that will solve all the issues in the food and agricultural system, particularly when it comes to the issue of food security in developing nations. To reduce food insecurity, the application of multiple complementary approaches, including new technologies, specialized agronomic management techniques, improvements in food processing and distribution, and localized and culturally appropriate education campaigns, is needed.

 

Further Exploration

 Nonfiction Books

  • Fedoroff, N. V., & Brown, N. M. (2004). Mendel in the kitchen: A scientist’s view of genetically modified foods. Joseph Henry Press.
  • Lynas, M. (2018). Seeds of science: Why we got it so wrong with GMOs. Bloomsbury Sigma.
  • Jenkins, M. (2017). Food fight: GMOs and the future of the American diet. Avery.
  • Regis, E. (2019). Golden Rice: The imperiled birth of a GMO superfood. John Hopkins University Press.
  • Nestle, M. (2010). Safe food: Bacteria, biotechnology, and bioterrorism. University of California Press.

 Documentaries

 

 

Organizations Working in This Area (not an exhaustive list)

 

Other Resources

 

 

Check Your Knowledge!

  • What bacteria is used to insert DNA into plant cells? Are there any alternative methods?
  • What does “substantial equivalence” mean when studying GMOs?
  • What are the differences in the regulatory processes between the United States and the European Union?
  • What are the challenges to the application of GMOs in developing economies?
  • Name three different GMO crops described in this chapter and explain their incorporated traits and benefits.

 

 

Synthesis Questions

  • Describe the process used for developing a GMO.
  • Explain the steps required to assess the safety of a new GMO crop.
  • What are the key points made by organizations against the use of GMOs in agriculture?

 

 

 

References

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