Gene-edited Crops made safer by CRISPR to ensure food security in the future

For a long time, scientists have been predicting and addressing that Gene Editing (GE) technology will play a vital role in climate change-proofing future Crops to protect global food supplies. Much research has been conducted with these GE technologies, and much ongoing research has been showing promising results that can assist humanity in facing the challenge of ensuring food security in the face of climate change.

According to scientists, global climate trends in many agricultural regions have been rapidly changing over the recent decades. Significant advances in global food systems are required to ensure food security in the face of these coming challenges. Scientists all over the world have been predicting that with increasing climate uncertainty due to rising carbon dioxide levels and warmer temperatures, the yields of worldwide agriculture will continue to be negatively impacted.

To produce more resilient and robust Crops with increased quality and yields at the same time under more extreme conditions and to face the growing concerns of climate change, scientists have to take more creative approaches.

A group of researchers from the University of Queensland earlier this year published a review paper demonstrating that the integration of transgenics and genome editing by CRISPR into current breeding strategies is one of the most promising solutions to accelerate genetic gains through targeted genetic alterations, producing Crops that can overcome the shifting climate realities.

What is CRISPR?

CRISPR technology is a simple yet powerful tool for editing genomes. It allows scientists to easily alter DNA sequences and modify gene function without interrupting the balance of gene sequences. Among many other potential applications improving Crops, treating and preventing the spread of diseases, and correcting genetic defects are some important applications that the current scientific world is exploring. However, its promise also raises ethical concerns. In popular usage, “CRISPR” is shorthand for “CRISPR-Cas9.” CRISPRs are specialized stretches of DNA. The protein Cas9 (or “CRISPR-associated”) is an enzyme that acts like a pair of molecular scissors, capable of cutting or silencing targeted strands of DNA.

CRISPR technology was modified from the natural defense mechanisms of bacteria and archaea. These organisms use CRISPR-derived RNA and various Cas proteins, including Cas9, to prevent attacks by viruses and other alien bodies by chopping up and destroying the DNA of a foreign invader. When these components are transferred into other more complex organisms, it provides a medium for manipulating or editing genes.

Until 2017, no one really understood how this process worked. In a paper published in 2017, a team of researchers led by Mikihiro Shibata of Kanazawa University and Hiroshi Nishimasu of the University of Tokyo showed what it looks like when a CRISPR is in action for the very first time.

Gene editing for climate change

The research team from the University of Queensland reviewed gene-editing technologies like CRISPR-Cas9 and showed that using this technology, it is possible to safeguard food security in the current farming system.

According to biologist Dr. Karen Massel, the lead author of the study, farmers have been altering the DNA of Plants according to their intention using conventional breeding technologies for millennia. Now with new gene-editing technologies, it is possible to do this with certain safety, speed, and exact precision. She pointed out that this type of gene editing mimics the way typical cells repair in nature.

In her review, she suggested integrating the CRISPR-Cas9 genome editing approach into modern breeding programs for Crop development in cereals. According to the observation of the researchers, just 15 Crop Plants contribute 90% of the world’s food calories. Among these, energy-rich cereal Crops like wheat, maize, rice, and sorghum contribute to two-thirds of the world’s food energy intake.

In this context, it is a race between unpredictable climate changes and Plant breeders’ ability to produce Crops with more tolerance that grow well in adverse conditions and have enriched nutritional qualities. The problem with the natural breeding system is that it takes a lot of time to detect and make that genetic diversity available to farmers. Typically, a natural breeding cycle averaged about 15 years for cereal Crops. On the other hand, CRISPR enables scientists to produce outcomes not possible through conventional breeding, to form novel diversity and develop breeding desired traits.

The research team and colleagues at the Queensland Alliance for Agriculture and Food Innovation (QAAFI) recently applied gene-editing technology to Barley and Sorghum pre-breeding programs for proof-of-concept studies. The research team edited the Plant’s genes to unlock the available protein’s digestibility level and boost its nutritional value for humans and livestock. They have also modified the root and canopy architecture of both Barley and Sorghum by gene-editing to improve water use efficiency.

Dr. Massel further explained that they are looking for genes or specific gene networks which will improve resilience in coming adverse environments. Once a viable gene variant is distinguished, the trick is to redesign it directly in high-performing cultivated Crop Plants without interrupting the delicate balance of genetics related to production traits. She reassured by stating that these kinds of changes can be so subtle that they are indistinguishable from the naturally occurring variants which inspired them.

Though gene-edited Crop Plants are not yet grown in Australia, Australia’s Office of the Gene Technology Regulator in 2019 withdrew the restrictions on Gene Editing (GE) by differentiating this technology from Genetically Modified Organism technology.

Conclusion

Gene-edited foods are already sold in some countries, including the U.S., and in late September 2021, Japan launched gene-edited tomatoes that appear to be the first food improved by CRISPR technology, a newer method than that used in the U.S. products. The UK was also considering reestablishing the regulations to distinguish the differences between Genetically Modified Organisms (GMO) and Gene-Edited (GE) food, and in September, 2021, took the first step to deregulate gene-edited Crops.

The EU is also rethinking its stance towards gene-edited Crops, with a review launched in April, 2021, calling the existing rules “not fit for purpose” because the regulations predate the development of CRISPR technology.

 

References

  1. BBC. (2021). Brexit paves the way for gene-edited crops, [online] Available at: https://www.bbc.com/news/science-environment-58711230 [Accessed 12th October 2021].
  2. Massel, K., Lam, Y., Wong, A.C.S. et al. (2021). Hotter, drier, CRISPR: the latest edit on climate change. Theor Appl Genet, [online] Volume, 134, p. 1691–1709. Available at: https://doi.org/10.1007/s00122-020-03764-0 [Accessed 12th October 2021].
  3. Ren, Q., Sretenovic, S., Liu, S. et al. (2021). PAM-less plant genome editing using a CRISPR–SpRY toolbox. Nat. Plants, [online] Volume, 7, p. 25–33. Available at: https://doi.org/10.1038/s41477-020-00827-4 [Accessed 12th October 2021].