Summary of CRISPR crops and food security potential
- CRISPR enables crops to resist drought heat disease and salinity
- Gene editing improves nutritional value adding vitamins and essential amino acids
- Crops can grow with less water fertiliser and land requirements
- Technology accelerates breeding for higher yields and sustainable agriculture
- EU eases rules on CRISPR plants despite ongoing safety concerns
Crops around the world are under pressure from high temperatures, unpredictable weather patterns and disease. Something must be done to protect them.
Gene editing in agriculture can make crops more resilient to pressures such as drought, heat and disease. Researchers are also using it to make crops more nutritionally dense, providing more nutrients in less food.
CRISPR-Cas is a particularly precise form of gene editing that has a lot of potential in the field of food security.
It is a relatively new technology, but it is already being used in industry. Tech start-up Pairwise, for example, has collaborated with Mars. Academic research, both in the UK and US, is also intently focused on CRISPR in agriculture.
However, it faces significant scepticism from regulators and NGOs over safety fears, as well as perceived risks of industry dominance in agriculture, particularly through patenting technology.
What is the potential of CRISPR as a food security technology. How can it protect the food supply, and enhance production?
What is CRISPR-Cas?
CRISPR-Cas is used as a gene-editing tool, which is particularly precise. It was “a revolutionary genome editing tool because it was highly programmable and highly precise and effective in a way that had never existed before,” explains Nicholas Karavolias, a plant biologist working with CRISPR.
Karavolias is speaking from the Innovative Genomics Institute in University of California, Berkeley, which was co-founded by one of the developers of CRISPR-Cas, Jennifer Doudna. Doudna, along with Emmanuelle Charpentier, won the Nobel Prize in Chemistry in 2020 for CRISPR-Cas.
In the natural world, CRISPR is an immune system used by bacteria to recognise invading viruses, and defend against them. Using the Cas enzyme, bacteria are able to destroy viruses.
Doudna and Charpentier were able to utilise this to develop a gene-editing tool, which they can guide to make targeted edits to genomes. Because CRISPR is so highly programmable and able to recognise its target, it is able to make highly precise edits to genomes.
By removing or editing the function of specific genes, CRISPR aims to create certain benefits.
Scepticism around gene editing
However, there is still significant scepticism around gene-editing, coming from a range of quarters.
NGOs such as Greenpeace have campaigned against gene-editing, citing safety fears. Specifically, the organisation fears that gene editing could introduce errors, which in plants could introduce novel toxins or allergens.
Other fears include that patenting of gene-editing techniques may put control of agriculture into too few hands.
Consumers themselves often display a mixed perspectives on gene-edited foods. While many are sceptical, others are more open-minded about the technology. One suggested that scepticism on the topic was less significant than of genetically modified (GM) foods.
In the EU, gene-edited crops have been heavily regulated. Until recently, they were considered Genetically Modified Organisms (GMOs) and subject to complex regulations and assessments before they could enter the market.
However, the EU’s regulations were somewhat eased last week. The EU come to a provisional agreement where many plants developed through new genomic techniques (NGTs), which include CRISPR, are exempted from GMO regulations.
NGT plants that are removed from the regulation are those roughly equivalent to what that can be found in nature or could occur through conventional breeding.
Karavolias emphasises that he respects these concerns, as eating is “one of the most intimate things that we do”. However, none of the data he has seen has suggested that there are any safety risks linked to the technology.
According to research conducted by Pairwise, most consumers have fewer concerns around CRISPR.
Nevertheless, “it is important to be transparent and deliver benefits they value,” says Scolnic.
Whatever the final outcomes of regulatory arguments might be, it is clear that CRISPR has a lot of potential in food security.
Editing crops to protect food security
While most famous for its use in editing human genes, CRISPR-Cas has also been used in plants, most notably crops, explains Karavolias.
A primary use case is to boost the pathogen resistance of crops. This can be highly beneficial for production, with crop disease often negatively impacting yields.
This is done by removing the function of susceptibility loci genes, which create pathways for disease, within the crop. It has already been used to successfully improve a litany of crops, from cassava to tomatoes to rice, as well as resistance to a wide range of infections, both bacterial and viral.
CRISPR can also be used to improve resistance to non-biological factors, like heat, drought and salinity (the amount of salt in the soil). It can even be used to boost the efficiency by which crops use nitrogen to grow.
Meanwhile, Rothamsted Research in the UK has developed a mildew-resistant wheat. Mildew can reduce yields of cereal crops by up to 20%, according to the Agriculture and Horticulture Development Board (AHDB).
By removing a protein that is recognised by the fungus, wheat that is no longer identified by mildew as a host has been created, explains Nigel Halford, group leader at Rothamsted Research. Allergens can also be removed from plants at a high rate, he explains.
However, not all crops are equal. Some are more amenable to having CRISPR delivered into their cells than others, explains Karavolias.
The good news is that it is the mainstream crops, like tomatoes, corn and rice, for which technology has been developed to improve, although working on minor crops like taro root is also the subject of research.
Boosting the nutritional density of foods
Alongside protecting crops from disease, drought and heat, CRISPR can also be used to boost nutritional density.
By using CRISPR to improve yields of minor crops, with more micronutrient diversity, such as millet, nutritional intake could theoretically be improved.
It can also be used to improve the nutritional quality of already widely-consumed crops. One use of this that has already been tried was editing a gene in bananas to induce them to produce more beta-carotene, a pigment that the body converts into vitamin A.
“It’s visually stunning. You see two different bananas, and the one that had been edited contains a much darker pigmented colour,” says Karavolias.
Rothamsted Research is also working to boost the nutritional density of certain foods, like increasing the prevalence of lysine, an essential amino acid, in cereal grains. They are normally deficient in lysine.
The benefits of this are twofold. In countries such as the UK, lysine-deficient barley and wheat for animal feed are being outcompeted by soybeans from abroad.
In lower-income countries, cereal crops with boosted lysine content can benefit humans, as it improves muscle growth and bone health.
Enhancing production through CRISPR
Food production can be boosted in several ways by CRISPR, explains Dan Jenkins, vice president of regulatory and government affairs at Pairwise.
Plants can be edited to be grown for longer periods of time. They can also be made smaller, taking up less space on the land. Required inputs like water and fertiliser will be less, and the land itself can be used more efficiently.
Pairwise itself has already improved its technology’s capabilities. While previously it focused on editing blackberries themselves, now it can edit the tree.
“Pairwise’s technology has expanded significantly,” says Lauren Scolnic, associate director of communications at Pairwise.
“In addition to improving consumer-focused traits like pitlessness in blackberry and other stone fruit, its Fulcrum platform can also address traits that benefit growers and producers as well, including plant stature, architecture, and optimized flowering and production windows across both bushes and trees.”
Improving the genetics in the traditional way, explains Jenkins, takes much longer than using CRISPR. Improving the genetics of a cherry tree could take a century, meaning that it’s obviously not economically viable for any company. Using CRISPR, this process can be sped up inordinately.
Pairwise’s technology allows it to delete and change letters in genes. Its technology is licensed out to larger companies such as Mars, as well as non-profits.
