An update on CRISPR-Cas Genome editing in plants

In 2019, our Facts series on genome editing was published. The revolutionary technology of CRISPR-Cas took biotechnology by storm, and questions from the public started to come in. Thanks to our publication, many of these questions were answered. However, science doesn’t stand still . New techniques and applications emerge every year, with new economical and societal impacts. Politicians around the world are adapting and updating their legislations in function of these scientific evolutions. In summer 2023, the European commission will propose a new regulatory framework on genome editing. At VIB we see this as the perfect opportunity to review our Facts series from 2019 and update you on how genome editing has evolved over the past 4 years, and what a changing legislation might mean for you.  

The technique 

The details of the technique can be read in our 2019 publication. While refinements are being made as we speak, the general functioning of CRISPR-Cas remains the same. After all, the CRISPR-Cas system is ancient and can be traced back to the bacterial immune system. The technique has already existed successfully in nature for thousands and thousands of years. It is only since 2012, that scientists were able to use this CRISPR-Cas system in other organisms like plants. The importance and implications of this research were acknowledged in 2020. That year, Emanuelle Charpentier and Jennifer A. Doudna received the Nobel prize in Chemistry for their research on genome-editing with CRISPR-Cas9. Claes Gustafsson, head of the Nobel committee for chemistry said ‘There is enormous power in this genetic tool, which affects us all. It has not only revolutionised basic science, but also resulted in innovative crops and will lead to ground-breaking new medical treatments’. ​ 

The new crops 

soytest fieldmaize

Our facts series from 2019 already mentioned the research on CRISPR Waxy Maize by Corteva Agriscience. The starch from ordinary maize kernels consists of 25% amylose and 75% amylopectin, while the grains of waxy maize contain almost exclusively amylopectin (97%). Amylopectin starch is easy to process and widely used in industry for the production of adhesives. What happened since 2019? In September 2020 Canada announced that Waxy Maize is considered equivalent to varieties already grown in the country. Therefore, Waxy Maize was determined as safe to use. (1) Also, governments in the USA, Brazil, Argentina and Chile have cleared Waxy Maize for release. Since CRISPR-Cas does not introduce foreign DNA into the plant, genome-edited products are not seen as GMO and therefore do not fall under the strict GMO regulation. The most recent update came in April 2023. Japan also gave green light to Waxy Maize (2) 

Later in 2019, Calyxt Inc. brought the first commercial high oleic soybean on the market in the USA. Oil from these beans consists of approximately 80% oleic acid and up to 20% less saturated fats compared to the conventional soybean. In practice this means that oil from these plants remains stable for a longer time when cooking (up to three times longer) and has a longer shelf life, making it a healthier and more sustainable product. The company continues to innovate. In 2020 they got clearance from APHIS (Animal and Plant Health Inspection Services) for their new HOLL soybean, meaning high oleic and low linolic soybean (3). 

In 2020, the ministry of Health, Labor and Welfare (MHLW) and the ministry of Agriculture, Forestry and Fisheries (MAFF) from Japan established clear guidelines on genome-edited crops. Under these guidelines, genome editing is not seen as GMO and therefore crops produced with this technology do not fall under strict GMO regulations. Later that year, Sanatech Seed Company, a start-up company from the university of Tsukuba, developed a tomato variety called “Sicilian Rouge High GABA” using CRISPR-Cas technology. This tomato produces higher GABA levels, a substance proven to have many benefits for human health such as lowering blood pressure. After extensive trials, the tomato came on the Japanese market in 2021, as the world’s first CRISPR-edited food. (4)(5) 

In 2021, the company Pairwise gathered funding for their research on improving the nutritional value and taste of leafy greens. Their nutrient enriched mustard leaf has higher levels of Vit C, Vit E, calcium, Vit B6, magnesium, and many more. Under the name of ‘Conscious Greens’, this will be the first food made with CRISPR technology to hit the market in the USA. Starting May 2023, it is available in restaurants and stores. Pairwise is currently also developing nutrient enriched berries, cherries, and other fruits (6). 

The latest success story is the non-browning banana from Tropic. This banana reduces the browning rate while ripening. According to Tropic, up to 60% of the exported bananas go to waste before reaching the customer. By reducing the browning process, Tropic not only hopes to reduce food waste, but also reduce the CO₂ emission from transport by up to 25%. This month, May 2023, the Philippines have given the non-browning banana from tropic a non-GMO exemption. This crop can now be imported and propagated freely in the Philippines. Tropic is already looking into the future by developing a banana resistant against the Panama TR4 disease, a disease that threatens 80% of the global banana production (7). ​ 

The European legislation 

Attentive readers may notice something in the list of crops above. The countries mentioned are mostly in Asia, North America and South America. Policy makers in these countries have concluded that crops produced with genome editing do not fall under strict GMO legislation. Argentina and Brazil were among the first to adapt a regulatory approach in which they exempt genome-edited crops from the scope of their GMO legislation on the condition that the introduced changes could also have occurred naturally or result from conventional breeding activities. Other countries have followed to introduce a regulatory regime that is similarly favorable to specific categories of genome-edited crops. This has also led to the first genome-edited crops being introduced onto the market: high-oleic oilseed soybean on the US market and tomato with increased levels of GABA on the Japanese market. ​ 

Europe remains to have one of the most stringent regulatory frameworks for genome editing in the world. For the EU, CRISPR-Cas falls under the GMO regulation. This means it is almost impossible for companies to meet the regulatory requirements and get genome-edited crops authorized. Only big multinationals have the financial means to afford the costs that come with these requirements, and even then, chances are not favorable. Importing a GM crop into Europe to be processed in food and feed is difficult but cultivating it on a field is nearly impossible. Although countries like Belgium, Spain, Sweden, and the Netherlands allow permits for field trials, this is not the case for bigger European countries like Germany and France. The result? Only one GM crop (insect-resistant maize) is cultivated in the EU. All other attempts to get crops authorized in the EU have been withdrawn. 

Is change coming? 2023 will be an exciting year for the answer to this question. In 2021, the European Commission initiated a process to develop new legislation for crops resulting from technologies like CRISPR-Cas. In 2022, this new legislation was presented to stakeholders. Through surveys and interviews, feedback was gathered that will form the basis of an impact assessment. Based on this, the European Commission intends to publish a new proposal for regulating crops resulting from technologies like CRISPR-Cas. They hope to do this in the summer of 2023. To be continued…. (8)(9).

Steve Bers

Science Communications Expert, VIB

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steve.bers@vib.be

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