Nature- The First Creator Of Transgenics

Varsha Gayatonde and Prudhvi Raj Vennela, PhD scholars, Department of Genetics and Plant Breeding, Banaras Hindu University, Varanasi, UP, 221005

2016-11-02 10:36:26



From the past three decades many scientists, policy makers, politicians, media, even the common men have been actively involving in the discussion of the effect of GMOs and recently the genetically edited food crops. When world’s one fourth of the pharma companies are involved in creating vaccines and curing diseases in vivo by editing technique, only plant modifications are the hot topics to discuss. Many of the transgenics proved safe but because of few problems the entire transgenic research has handicapped. Genome editing in crop improvement is still at infant stage. Even now the world is discussing either to consider the genome editing crops same as GMOs (Genetically Modified Organisms)? How far this thinking is fruitful?

 Perhaps one of the most dangerous thing ruled last century even ruling today are the chemicals and mutagens used in agriculture. They are not only carcinogenic but also left a long side effect on the farmers’ pedigree. Many of them became the reasons to cause air pollution, ozone damage, creation of super weeds, health hazards, disturbed food chains, pest and disease outbreak etc. but when the world has full need of more food these things pretended negligible, when scientists seriously thought to get out of these problems and came out with transgenics, our only focus is to imagine the future side effects and fear of losing our indigenous cultivars. But this thinking is totally unscientific. After 2002Bt (Bacillus thuringiensis)-cotton replaced the traditional varieties across India still there is enough cotton varietal diversity and they can be used to create a new genetically modified/traits stacked variety to avoid the chances of resistance development by the insects.  Many transgenic crops proved safe e.g. Golden rice, recently mustard etc. but not getting wide public acceptance except Bt-cotton.

 The biggest misconceptions about GMOs, is that they are unnatural. When the primitive human still in search of fire and a firm life, nature was busy in modifying the genetic structure of plants and animals. Nature has always had its own process of transferring genes from one species to another, in effect, creating GMOs. Human understood this quite late.  What today’s genetic scientists have done is harness nature’s process to bring about specific genetic alteration in a much more controlled way. The technology enables us to modify plants by a process that is more directed and rapid than is possible through traditional plant breeding, important to the environment and our future survival.

 Agrobacterium, a microbe causing crown galls on plants is the best example for natural genetic engineer. This tiny microscopic creature delivers a genetic package, called T-DNA, to a plant. They proved it in sweet potato which is not a tuber like potato but a swollen root. Now, we cannot find any sweet potato without this Agrobacterium gene. It infects more than 140 species.So why does an 8,000-year-old GM sweet potato matters? The example might be helpful for regulators and scientists looking at the safety of GM crops, as it is consumed as a traditional crop worldwide.

 Genome editing is a process copied from the bacteria escaping the viral phage particlesattack (CRISPR-Cas-9). These competences integrate the whole toolbox of natural genetic engineering, replication, transcription, translation, genomic imprinting, genomic creativity, enzymatic inventions and all types of genetic repair patterns,it was possible to alter this genetic package so that useful genes could be transferred to the plant, improving it in a number of ways.

Evidences to prove GMOs are not harmful: Genetically engineered (GE) crops are not different from conventional crops in terms of their risks to human health and the environment, according to a report published in May 2016 by the U.S. National Academies of Sciences, Engineering, and Medicine.Many people are concerned that consuming GE foods may cause cancer, obesity and disorders such as autism spectrum, chronic disorders, birth defects and allergies but when the survey conducted in the United States and Canada, where GE food has been consumed since the late 1990s, and similar datasets from the United Kingdom and Western Europe, where GE food is not widely consumed. There were no differences among countries in specific health problems.The future concern regarding GEs from many NGOs and pseudo-environmentalists is worries about the herbicides, monocultures, and patents. But none of these concerns is fundamentally about genetic engineering. Genetic engineering is not a thing.It is a process that can be used in different ways to create different things.

 In 1998 Hawaii scientists became responsible for the widespread of GM papaya, against ring spot virus. Even though thousands of people consumed it for many years no harm reported. But a group argued that it has allergic protein made by worms and they reported it as “playing with nature”. Some of these early alarms were disconcerting. But scientifically, they made no sense.

 A Swiss Scientist, Ingo Potrykus in 1999 introduced golden rice with an idea of providing Vitamin A supplement to the poor people who can’t afford to buy costly medicines or other food supplements. At the first stage when his team introduced genes from Daffodils and bacteria Erwinia, people opposed it by stating it doesn’t have enough Beta carotene to overcome Vitamin A deficiency. In the second stage when he introduced a gene from maize, they said it contains over Beta- carotene which may cause the birth defects. But these were myths.  Even though golden rice has capacity to cure millions of poor till today it became unable to reach the market. This was a sustainable solution.

According to the report, Bt crops, those that contain an insect-resistant gene from the soil bacterium Bacillus thuringiensis, comprise a large segment of GE cropland. The researchers found that from 2002 to 2016, the use of Bt cotton contributed to a reduction in synthetic insecticide use and in crop losses. Some pest-insect populations dropped; however, insect biodiversity increased overall. Insect resistance to Bt proteins was slow to develop only when the crops produced a dose of Bt protein that was large enough to kill insects. The activation of Bt protein in resistance breeding just means that the protein is truncated, which helps it bind to the guts of insects. And each Bt plant is different. A global database of GE crops, maintained by the Center for Environmental Risk Assessment, shows that some Bt proteins are fully truncated while others are partially truncated. Even the fully truncated proteins are just “semi-activated,” Unless you’re a bug, Btcant be active. Damaging levels of resistance did evolve in some species when resistance-management strategies were not followed.

India in 2010, the environment ministry put on hold the commercial planting of Bt-brinjal, equipped with a bacterial gene that thwarts insect pests. The moratorium continues and is unlikely to be lifted anytime soon. If the ban will be removed there are 32 other GM crops to release for different traits in the pipeline.

  India is one of the world’s biggest producers of mustard(Brassica juncea), which is cultivated for its edible leaves and oil. The GM mustard variety is equipped with genes from a soil microbe that manipulate pollen development such that the variety produces hybrids more easily in the usually self-pollinating crop. The GM-derived hybrids produce about 25% more seeds—and thus more oil, which is pressed from the seeds—than traditional varieties now in cultivation. It proved safe and now the review committee suggested to study the kind of effects on honey bees and honey production in mustard-growing area and it calls for continued monitoring of insects and other organisms that live in or near mustard fields. (Science report, Sept, 2016).

Why we need GMOs?If we consider the environmental benefits and agricultural efficiency, by making croplandmore productive, with less output lost to weeds and insects, GMOs reduce the amount of land that has to be farmed and the amount of water that’s wasted. Herbicide-tolerant crops even mitigate climate change by reducing the need to till fields, which erodes soil and releases greenhouse gases.Scientists have perfected the technique and identified genes that improve the taste and freshness of the foods, even enhancing the shelf life of fruits and vegetables to store for a longer period. Other genes allow for growing higher-yielding crops in harsh conditions.Growing crops with fewer resources is good for the environment, and even better for farmers struggling with low income and water scarcity.

            Across the globe by using genome editing tools and GM techniques Bt-corn; cotton; conola and soybean, golden rice, drought-tolerant corn, virus-resistant plums, non-browning apples, potatoes with fewer natural toxins, and soybeans that produce less saturated fat are already developed. The projects under the pipeline are: virus-resistant beans, heat-tolerant sugarcane, salt-tolerant wheat, disease-resistant cassava, high-iron rice, and cotton that requires less nitrogen fertilizer, high-calcium carrots, antioxidant tomatoes,non-allergenic nuts, bacteria-resistant oranges, water-conserving wheat, corn and cassava loaded with extra nutrients, and a flaxlike plant that produces the healthy oil formerly available only in fish. Phytoremediation- to take out the environmental pollutants, bio-pharming- to produce vaccines by making plant as factory are the some other utility of GM.Some of the issues yet to be addressed before the complete approval of transgenic foods in India are:

1.      Concentrating on maintaining the genetic diversity, to avoid the resistance by some biotic factors e.g.Bt cotton became susceptible to pink boll worm and white fly recently.

2.      Making seeds affordable and training the farmers: These seeds are costly, to make it available to the farmers,’ large scale seed production under the regulations and supervision with public private partnership.Farmers should be trained about the handling and cultivation these crops.

3.      Some advanced clinical trials to analyzethe long term effect of transgenics on human, animal, insect and environment.

4.      The process of genome editing is entirely different from transgenics, therefore there should be separate regulations. 

5.      Regulations on herbicide resistance transgenics which consume more herbicides and pollutes the environment, may even generate super-weeds.

Instead of many controversies now people are at a door step to accept the engineered modifications in crops. In India the scientific community is looking forward for the properly framed governmental policies, regulations to grow and release these crops which may meet our food demands and reduce the over dependency on the costly chemicals and infrastructure to protect the food for a longer period. The only way to end this fight is to educate ourselves and make it clear to everyone. We want the transgenics for our healthy survival, to embrace nutritious, environment friendly food, no matter where it got its genes.While many nations enjoy relative abundance in food today, that won’t necessarily be true in the future. The Indian population is growing at the geometric rate, within the next few decades there is a need to produce enough extra food, on top of what is produced today. Tomorrow’s GMO and edited crops—carefully designed and tested to yield nutritious food using less water, less land, less fertilizer and fewer pesticides—are going to be the key to ensuring the national food security.