Can CRISPR Technology Help To Feed The India

Monica Jolly, Veda Krishnan, Smruti Saha, Ashish marathe, Shelly Praveen and Archana Sachdev. Division of Biochemistry, Indian Agricultural Research Institute (IARI), New Delhi-110012

2019-10-14 09:22:31

Credit: pixabay.com

Credit: pixabay.com

The way world is moving towards technology, time is not far that we will totally indulged into artificial complex  lifestyle full of health complexities. Hidden hunger is an alarming global tsunami and controlling this in any  manner is an affordable opportunity to improve the lives of more than half of the world population especially  developing countries (UNICEF report, 2017). New developments are leading to rising carbon levels making food  less nutritious which brings nutrition crisis. In the current scenario, the paradox is while the number of  undernourished people has gone down by one-third in the last decade, but the mal- nutrition is increasing  to an alarming ratio and this could be related to the increase in Co2 level. Hunger around the world is  rising again, high CO2 level is jeopardizing the progress made to end the scourge of food insecurity.  Why rising carbon levels are bad for Indians as it is making rice and wheat less nutritious, putting  millions at risk of malnutrition. The anti-nutritional effects and environmental implications has  instigated numerous studies and aimed at how to stabilize the plant nutrition. Gene editing is the need  to solve this incumbency of nutrition.

Currently India is well poised to become the third largest economy in the coming decades though it is still notorious for being undernourished facing the major challenge of hidden hunger. Although we boast that India is set to become the youngest nation by 2020 with a huge workforce of 64%, the reality is the hidden hunger, which may be due to the rising carbon dioxide (CO2). The time is come where we have to address the nutrition security than the food hunger. High carbon dioxide leads to lower concentration of protein, iron, and zinc in the crops. Cereals and lentils are most affected if grown under polluted environment. In India millions of people are facing nutritional deficiencies because of rise in carbon dioxide. Rising carbon dioxide making staple food such as rice and wheat less nutritious. By recent survey it is reported that by year 2050 millions of people are at risk of becoming nutrient deficient. Researchers at Harvard T.H. Chan School of Public Health in the US found that rising CO2 levels from human activity could result in 175 million people worldwide becoming zinc deficient and 122 million people becoming protein deficient by 2050. The study, published in the journal Nature Climate Change, also found that over one billion women and children could lose a large amount of their dietary iron intake, putting them at increased risk of anemia and other diseases. ‘Hidden hunger’ refers to a more insidious type of deficiency of vitamins and minerals (Iron, zinc and calcium)in the diet contributing serious health constraints with two extremes - on one side it cause growth retardation, physical disabilities and compromised intellect and on the other hand overweight or obesity with weak immune systems and low life expectancy. It has been also observed that India would bear the greatest burden, with an estimated 50 million people becoming zinc deficient. As many as 38 million people in India are at the risk of becoming protein deficient, and 502 million women and children becoming vulnerable to diseases associated with iron deficiency, the researchers said. Other countries in South Asia, Southeast Asia, Africa, and the Middle East would also be significantly impacted, they said. Presently, over two billion people worldwide are estimated to be deficient in one or more nutrients. In general, humans tend to get a majority of key nutrients from plants: 63 % of dietary protein, 81 % of iron and 68 % of zinc comes from vegetal sources, researchers said. It has been shown that higher atmospheric levels of CO2 result in less nutritious crop yields, researchers said.

Concentrations of protein, iron, and zinc are 3-17 % lower when crops are grown in environments where CO2 concentrations are 550 parts per million (ppm) compared with crops grown under current atmospheric conditions, in which CO2 levels are just above 400 ppm. Researchers sought to develop the most robust and accurate analysis of the global health burden of CO2-related nutrient shifts in crops in 151 countries. They created a unified set of assumptions across all nutrients and used more detailed age- and sex-specific food supply datasets to improve estimates of the impacts across 225 different foods.The study showed that by 2050, when atmospheric CO2 concentrations are expected to reach around 550 ppm, 1.9 % of the global population — or roughly 175 million people, based on 2050 population estimates — could become deficient in zinc. About 1.3 % of the global population, or 122 million people, could become protein deficient, researchers said. Additionally, 1.4 billion women of childbearing age and children under five who are currently at high risk of iron deficiency could have their dietary iron intakes reduced by four percent or more. The researchers also emphasized that billions of people currently living with nutritional deficiencies would likely see their conditions worsen as a result of less nutritious crops. “We cannot disrupt most of the biophysical conditions to which we have adapted over millions of years without unanticipated impacts on our own health and wellbeing,” Myers said.

According to a recent survey-need of the time is that we should be more concerned with the basic requirements and the new development should not hamper the basic lifestyle needs. We are developing new infrastructure which should not be at the cost of poor environment. Research has to be in such an orientation that will take into consideration of the side and ill effects as well. Currently it has been observed that decisions we are making with respect to everyday instances – whether its use of new gadgets, heating homes, diet and cooking pattern, mode of transport- are making our food less nutritious and imperiling the health of other populations and future generations,” said Sam Myers, principal research scientist at Harvard Chan School .

To improve the nutritional properties of the staple crops: targeted genome editing seems to be the only criteria. This genome editing technology has dual advantage of not only enabling selective gene modification but also serving as a versatile tool to generate transgenic -free genetically edited crops. The undesirable phenotypes and poor consumer acceptance of previously used forward and reverse genetics approaches have necessitated the use of a more targeted, efficient and socially acceptable intervention like the recently developed CRISPR/Cas9 system. CRISPR/Cas9 is an efficient strategy that has been gaining wide consumer acceptability and in addressing the complications with the prior approaches.  CRISPR-Cas9 is a genome editing tool that is creating babble in the biotechnology world. It is faster, cheaper and more accurate than earlier tools of editing DNA and has a wide spectrum of potential applications.

Thinkers opined it as a new gene editing technology called CRISPR to create genetic mutations in a more subtle way which is faster and cheaper than previous techniques. “It’s different from a classical GMO in that we’re not adding a genome from another organism,” Gmitter says. In CRISPR we are  knocking out a few existing genes. CRISPR (clustered regularly interspaced short palindromic repeat)/Cas (CRISPR-associated) system, a technology for gene editing, for genome engineering in various organisms. Streptococcus pyogenes Cas9-guide RNA (gRNA) has been successfully applied to generate targeted mutagenesis, gene integration, and gene editing in several species including soybean (Glycine max).

With the advent of sequence-specific nucleases, including TALENs and CRISPR/Cas, it has become possible to introduce targeted knockout mutations within genes of interest. The CRISPR/Cas9-based genome editing system having several advantages, including simplicity of vector design and construction, capability for multiplex genome targeting, and high editing efficiency can be effectively used  to generate targeted DNA double-strand breaks which are then repaired predominantly by non-homologous end joining (NHEJ). Small insertions or deletions introduced at the repair site within gene coding sequences by imprecise repair by NHEJ have the potential to introduce frame shift mutations or in-frame deletions that destroy protein function. The possibility of off-targeting, which is a critical issue can however be minimized by specific target selection, and can be easily eliminated, if necessary, by crossing (and back-crossing) the mutant plants with their parental lines. Also the CRISPR/Cas9-induced genome editing in plants depends on stable genetic transformation, primarily utilizing Agrobacterium-based binary constructs that can transfer T-DNAs containing both Cas9 and sgRNA(s) expression cassettes (together with a plant selectable marker gene). These lines would prove to be nutritionally more beneficial and socially more acceptable to public, side stepping the current issues much associated with the existing transgenic strategies.

Most of the transgenic technologies like RNAi although capable of producing plants with desirable phenotypes, the process for obtaining a plant in this manner is time-consuming, costly and potentially risky. Using site-specific nucleases, these issues can be tackled to produce plants in a single generation. CRISPR/Cas9 gene targeting has not been much reported so far in quality improvement.

This technicality is not transgenic though no final decision has been announced, but so far regulators say the CRISPR’d crops are non-GMO. The agriculture industry could have the benefits of genetic modification without the stigma. Genetically modified organisms (GMO) have had genetic material added to them from other organisms. So far, CRISPR has only been used to remove bits of DNA. From scientific point of view, gene editing is a completely new way of altering genes. "Plants that were produced with CRISPR cannot be distinguished from plants that were naturally bred," Kogel says. "And unlike natural breeding, gene editing allows for deliberate and precise changes with extremely little risks." Since ages breeders are creating genetic crosses to increase disease resistance, yet recently scientists could decipher how it worked: Plants and animals both rely on a major class of disease resistance genes.

Many bacterial diseases infect plants using what scientists call a type-III secretion system. That’s a rather boring name for a robust, destructive little molecular machine. This machine’s main objective is to inject proteins that disarm the plant’s immune system. But the battle isn’t totally one-sided. Once the disease resistance genes kick in, they trigger a cascade of effects to fight off the infection.You can get those disease resistance traits through crossbreeding, but doing so also pulls in genes that could diminish the crop. CRISPR’s precision lets scientists select specific genes from a plant’s relative — wild or domestic — and insert only the desired traits. Scientists can also simply knock out a gene that leaves a plant susceptible to disease.

“The technology is robust, and it’s simple,” Staskawicz says. “A lot of people can do it, and you don’t need fancy equipment.”

CRISPR/Cas9 is a recent addition to the repertoire of technologies is Genome Editing. At a meeting of the National Agricultural Biotechnology Council (NABC) in 2014, leading agricultural scientists discussed the pros and cons of this tool CRISPRs/Cas9 to crop plants and farm animals. According to them product of gene editing technology cannot be classified as transgenic or genetically modified as per most legal definitions of genetic engineering used by regulatory agencies. The crop improvement research programs have gained impetus by the demonstration of CRISPR/Cas9/gRNA-mediated targeted gene modification in Arabidopsis, tobacco, sorghum and rice with in this short time. This technology has enormous potential and will undoubtedly pave the way for identifying novel methods in enriching nutrition, designing crop resistance etc. The public misunderstanding and mistrust of GMOs should not hinder the scientific progress and valid uses of CRISPR and India must not allow regulatory confusions and luddite activism to deny itself the benefits. Thinking through—and getting right—the regulations and research ethics for these applications of CRISPR might also help to create an ethical framework. Being a recent technique, environment impact assessment has to be closely monitored and cannot comment in the present context. Dynamic and flexible policies to accommodate rapid advances in technology and to facilitate commercialization for safe and for nation’s economic progress should be framed. Regulations must be facilitators of safe technology transfer for the benefit of society.

SCREENING AND CONFIRMATION OF TRANSGENICS

There should be a joint partnership from public and private agencies to work for the eradication of crop nutrition. These days the companies / organizations are working on altering the plant genes to produce   healthier, nutritionally rich food using the editing technique rather than genetic modification. Even farmers are getting educated to use gene – edited crop to sell commercially. The time will come that we will have  plant ATMs/ plant centers where we can get all the best quality seeds according to the need of the farmers based on the soil and climate conditions. Many private companies specially Monsanto, Syngenta and Dow-Dupont  were using genetically modified crop technology in the 1990s, but now we have switched to gene- editing crops as it has lower development costs and USDA has also decided not to regulate GMO crops, since that involves transferring a gene The need of the time is for potentially advanced gene-edited transformation technology i.e. CRISPR . CRISPR-associated protein 9 (Cas9) has the potential to accelerate basic research as well as plant breeding by providing the means to edit genomes rapidly in a simple, precise and a predictable manner. This tool has the potential to up- regulate or down-regulate genes in ways that are not transgenics, thereby giving CRISPR edits a rare opportunity to escape GMO definition as described in the current regulatory sense.

  1. Harvard T.H. Chan School of Public Health. "As CO2 levels climb, millions at risk of nutritional deficiencies." ScienceDaily. ScienceDaily, 27 August 2018. 
  2. Matthew R. Smith, Samuel S. Myers. Impact of anthropogenic CO2 emissions on global human nutritionNature Climate Change, 2018; DOI: 10.1038/s41558-018-0253-3.
  3. Surender KhatodiaKirti BhatotiaNishat PassrichaS. M. P. Khurana and Narendra Tuteja (2016 ). The CRISPR/Cas Genome-Editing Tool: Application in Improvement of Crops.Front. Plant Sci., | https://doi.org/10.3389/fpls.2016.00506.
  4.  “सोयाबीन के पोषण संबंधी गुणों में सुधार हेतु: लक्षित जीनोम संपादन(Targeted Genome editing CRISPR/Cas9)”. मोनिका जौली, वेदI कृष्णन, विनुथा  टी,  शेली प्रवीण, अर्चना सचदेव(2018)   Bharatiya Vaigyanik Evam Audyogik Anusandhan Patrika (BVAAP) NISCAIR, 26 (63-68).