Next phase of Agriculture; CRISPR editing crops
SADAF SALEEM
Department of Plant Breeding and Genetics, University of Agriculture Faisalabad.
Genetically modified organisms (GMOs) production was one of the leading genetic engineering techniques in agriculture in previous decades. Monsanto is world’s famous corporation regarding production of Genetically Modified food crops. Simply GMOs could be understand as insertion of new gene in plant or existing genes are modified for getting some desirable traits e.g., insect pest resistance, drought tolerance, higher yield, quality traits, improved nutritional and processing quality etc. It provides an easy and faster approach to obtain healthy, fresh and disease free food. Mostly the GMOs are similar to their non-GMOs counterparts for nutrition and taste. Majority of GMO crops are corn (USA) 88%, canola (90%), cottonseed (90%) and sugar beet (95%). Other commercially grown crops are potato, papaya and squash. In America, according to Grocery Manufacturing Association, almost 75% of processing foods are GMOs. In Pakistan Bt-cotton is grown on almost 80% and of major crop grown areas. But on the consumer’s side, GMO foods faced lack of acceptance and were considered worse for health by majority of people. A negative perception about GMOs was strengthen by a claim in 2013 that genes from GMO food may somehow incorporate into your genes and cause some non-desirable and irreversible effects to consumer. This lead to discouragement to use of GMO foods and several marches were conducted to stop producing GMO foods. However scientists and many other leading companies associated with GMOs production and selling continue convincing that public was misguided and till now no exact evidences have been found that GMOs are harming plants, animals or humans by altering their genomes. Increasing concerns against GMOs always put forward a need to find alternate genetic engineering tools and move over GMOs.
CRISPR (Clustered regularly interspaced short palindromic repeats); a novel gene editing technology considered more precise than previous genetic engineering techniques which attracted the attention as it allows scientists to delete, add or modify a gene at their will. Recently CRISPR is broadly used by pharmaceutical companies and universities. Researchers in biomedical field are conducting trials for its potential applications in humans to find out its actual working and consequences in individual. Dr. Robert Fraley, Monsanto’s Chief Scientific Officer in May 2017 announced that Monsanto is experimenting with gene editing (CRISPR/Cas 9) in food crops. That will probably make a big difference by allowing scientists to edit plant genes without facing unease of foreign gene transfers as was in GMOs. Moreover expectations are CRISPR edited food crops would be accepted by consumers as it precisely modifies plant, animal or human existing genes and nothing to do with foreign DNA insertions as was in GMOs.
Last year scientists developed a mushroom using CRISPR editing technology, in which they knock down the genes related to turning the mushroom brown to reduce food waste and increase its shelf life.
Recently researchers in Norwich UK are working to produce pathogen (Phytophthora infestans) resistant food crops. Prof. Kamoun working to develop potato blight and wheat blast resistance using CRISPR-Cas 9 suggested; it is very convenient with CRISPR to remove gene that makes a plant vulnerable to disease. It is revealed that CRISPR will also be use ahead in key cereal crops, brassica, tomato and other vegetables. It could serve as potential breakthrough in crop improvement to meet world growing food demands.
A research published in Scientific American on 19 May reports a team of scientists at Cold Spring Harbor Laboratory in New York used CRISPR-Cas 9 gene editing to develop more productive tomato plants. CRISPR-Cas 9 editing is also being used by scientists at the University of California, Davis against citrus disease “citrus greening’’.
Conclusion
CRISPR is scientifically easier than conventional genetic engineering tools by saving time and money. But it could not be neglected that there could be ‘off-target’ genome effects so adequate testing and investigation of long term feeding effects is needed. Moreover plant cells have complex interconnected systems. A single gene has systematic effects and editing a single gene could affect the several interconnected systems and may result in large alterations in biochemical concentrations than expectations.
References
Spisák, S.,et al. (2013). “Complete Genes May Pass from Food to Human Blood.” PLOS ONE 8(7): e69805.
Nature, 545, 277–278,(18 May 2017), doi:10.1038/545277a
Nature, doi:10.1038/nature.2017.22018
Horizon-magazine.eu, Can CRISPR feed the world?, (May 18, 2017).