The agriculture industry has been valued at an estimated US$ 3.2 trillion worldwide and accounts for a large share of the GDP and employment in developing and underdeveloped nations.
It has been estimated that hunger affects an estimated 1 billion people many of whom live in countries with developing economies. Population growth and decreased availability of arable land will continue to confound this issue.
Modern biotechnology has the potential to be a significant tool in fighting hunger as it has been well established to address agricultural problems such as yield loss from insect infestation, completion with weeds, and even drought.
Biotechnology has been used to improve the quality and yield of field crops in many parts of the world for more than 20 years. It is more specific and relatively fast in development compared with traditional breeding techniques.
GMO can be defined as “organisms (i.e. Plants, animals or micro-organisms) in which the genetic material (DNA) has been altered in a way that does not occur naturally by mating and/or natural recombination is a biological technique that affects alteration in the genetic machinery of all kinds of living organisms.
The definition seeks to distinguish the direct manipulation of genetic material from the millennial old practices of improvement in the genetic stock of plants and animals by selective breeding. With DNA recombinant technology, genes from one organism can be transferred into another, usually unrelated organism.
“GM foods” refer to food produced from genetically modified plants or animals. The first genetically modified plants, antibiotic resistant tobacco and petunias, were produced by three independent research groups in 1983. Scientists in China commercialized genetically modified tobacco in early 1990s.
In 1994 the US market saw the first genetically modified species of tomato with the property of delayed ripening approved by the Food and Drug Administration (FDA).
Since then, several transgenic crops have received FDA approvals, including Canola with modified oil composition, cotton and soybeans resistant to herbicides etc. GM foods that are available in market include potatoes, eggplants, strawberries, carrot and many more in pipe line.
Papaya has been developed by genetic engineering which is ring spot virus resistant (Papaya ringspot virus (PRSV)), a member of the aphid‐transmitted genus Potyvirus, is the cause of a destructive disease and a major limiting factor for papaya and cucurbit cultivation worldwide.) resulting in enhanced productivity. On the other hand, cooking oil, margarine and fat used for making pastry may also be made from several crops.
A large percentage of canola produced in USA is GM and is mainly used to produce vegetable oil. Canola oil is third most widely consumed vegetable oil in the world.
The genetic modifications are made for providing resistance to herbicides viz. glyphosate or glufosinate and for improving the oil composition. After removing oil from canola seed, which is app. 43%, the meal has been used as high-quality animal feed.
Maize which is ground, and dried maize constitute a staple food in many regions of the world. Grown since 1997 in the USA and Canada, 86% of the USA maize crop was genetically modified in 2010 and 32 % of the worldwide maize crop was GM 2011.
Maize crop can be used in animal feed, ethanol production and high fructose corn syrups production also used for other sweetener, corn starch, alcohol and human food or drink.
In order to generate GM foods, researchers need to introduce the gene(s) coding for certain traits into a plant cell, and then regenerate a plant through tissue culture.
When and where the transferred genes is expressed is usually inherent in the scheme to optimize the property of the product. There are three ways to modify genes in the cell. (1) Directly transfer DNA (2) Indirectly using bacterial vehicle (3) Direct editing of genomic DNA.
It is important to know why there is such great effort to develop GM foods. There are three major challenges we are facing that motivate our resort to the new technology for help.
The rate of increase in crop yield is less than 1.7% whereas the annual increase in yield needs to be 2.4% to meet the demand of population growth, improved nutritional standards and decreasing arability.
This goal can be achieved by means of optimization of crops genetics coupled with quantitative improvements in management of the agricultural system.
FAO predicted that finite amount of arable land available for food production per person will decrease because of population growth and mechanization.
Ability to bring additional acreage under cultivation seems limited must come from greater agricultural inputs, such as fertilizer, water, pest and weed control and genetic improvement.
This scenario is compounded by several complicating factors: (1) the increased demand for biofuel and feed stock production (2) accelerated urbanization (3) land desertification, salinization, and degradation (4) altered land use from staple foods to pasture driven by socioeconomic consideration .
There were questions about whether foods obtained from them were safe to eat. Organization for Economic Co-operation and Development stated “If a new food or food components is found to be substantially equivalent to an existing food or food component, it can be treated in the same manner with respect to safety.
No additional safety concerns would be expected (OECD, 1993).” This prescient concept remains the basis of safety assessment of foods from GM crops today.
Safety assessments are designed to ensure that the developer did not select a protein to which a sensitive person could be exposed to unknowingly. Potential for allergenicity is assessed for proteins to ensure that they are not similar enough to cross react with the antibodies present in persons with food allergies.
The source of protein is an important criterion in selection for protein of interest. This is one component of the safety assessment for individual proteins called History of Safe Use (HOSF).
Another key component in the allergenicity assessment is a bioinformatics comparison of the amino acid sequence of the protein with the sequences of known allergenic proteins for similarity using computational methods.
Collectively these studies have successfully demonstrated that the methods used to assess the allergenicity of proteins expressed in GM crops are effective.
Nearly 20 years following commercialization of the first GM crop there have no reports of allergic reaction that are attributable to exposure to foods obtained from them.
In addition to allergenicity, some proteins are known to exist in nature that can cause adverse effects when consumed. Though many are found in venomous snakes and insects or are produced by pathogenic bacteria, there some that are found in plants such as kidney beans lectin and ricin.
Accordingly, proteins used in GM crops have also been assessed for potential to cause adverse effects if for no other reason that they too are proteins.
Countries in which GM crops have been developed have benefited from agricultural biotechnology and countries with developing economies will also benefit from application of this technology.
The standards followed for safety assessment of foods from GM crops are comprehensive and have proven very effective. Countries with developing economies will also benefit from key learnings with early generation GM crops and applying them to a different range of field crops for products developed in their own countries.
GM crops can mitigate several current challenges in commercial agriculture. Current market trends project them as one of the fastest growing and innovative global industries, which not only benefit growers but also consumers and major country economies.
However, it is imperative that the agricultural industry and science community invest in better science communication and regulation to tackle unethical research and misinformation.
With key innovation in precision gene-integration technologies and emerging research in biofortification and stress tolerance, GM crops are forecast to bring productivity and profitability in commercial agriculture for smoother progress in the future.
In the intermediate future, GM foods and feeds will prosper in the Asian and African countries, as is evident from the growth of these product during the last 5 years (ISAAA, 2015).
However, the mature GM crop markets, such as those in the US, Brazil, and the EU have little scope for expansion. Soon, it is expected that there will be more releases of GM crops with stacked traits carrying multiple stress tolerance genes, given that in the 2015 ISAAA brief there is mention of 85 GM products in the pipeline.
The applications of more precise, rapid, and well-regulated technologies, such as CRISPR (clustered regularly interspaced short palindromic repeats), CRISPR-associated (Cas) genes, and new breeding technologies, will increase in usage as these technologies come under proportionate legislation with an advantage of being science-based and appropriate for the purpose.
Regarding safety assessment and health hazards, there will be a need for more precise, animal-specific, organ-specific, and long-term assessment procedures, with special consideration given to novel toxins, dose, potentially toxic mixtures and the combined effect of stacked traits on metabolism and other body mechanisms.