Many small regulatory elements, including miRNAs, miRNA binding sites, and cis-acting elements, comprise only 5~24 nucleotides and play important roles in regulating gene expression, transcription and translation, and protein structure, and thus are promising targets for gene function studies and crop improvement.
Few technologies have made as big a splash in recent years as CRISPR/Cas9, and rightfully so. CRISPR/Cas9, or clustered regularly interspaced palindromic repeats (CRISPR) and associated genes, is a bacterial gene editing toolbox that allows researchers to edit genomic sequences much more precisely and efficiently than previously possible, opening up doors to new ways of doing research. As with many new biotechnologies, the application of CRISPR in biology began with genetic model organisms such as Arabidopsis thaliana. In recent research authors review the prospects for expanding the use of CRISPR for research beyond genetic model plant species.
Experts’ interest in utilizing gene editing for the breeding crops has seen revolutionary growth. Meanwhile, people’s awareness for food safety has also been increasing.
According to a study, participants who had expert knowledge of molecular biology perceived emerging technologies to offer the lowest risk and highest benefits or value for food application, while lay public showed the highest risk and lowest benefit.
Field trials show that poplar trees can be genetically modified to reduce negative impacts on air quality while leaving their growth potential virtually unchanged
A research team recently developed new methods that will make it significantly faster to produce gene-edited plants. They hope to alleviate a long-standing bottleneck in gene editing and, in the process, make it easier and faster to develop and test new crop varieties with two new approaches.
Researchers have developed a set of tools that make it faster and easier to modify large segments of DNA. The new tools are for use in a technique called recombineering.
New research has found that the European Union’s opposition to modern crop breeding is at odds with the majority of other countries around the world and could jeopardise international trade.
At July’s New Breeding Technologies workshop held in Gothenburg, Sweden, Dr. Staffan Eklöf, Swedish Board of Agriculture, gave us an insight into their analysis of European Union (EU) regulations, which led to their interpretation that some gene-edited plants are not regulated as genetically modified organisms. We speak to him here on the blog to share the story with you.
Could you begin with a brief explanation of your job, and the role of the Competent Authority for GM Plants / Swedish Board of Agriculture?
I am an administrative officer at the Swedish Board of Agriculture (SBA). The SBA is the Swedish Competent authority for most GM plants and ensures that EU regulations and national laws regarding these plants are followed. This includes issuing permits.
You reached a key decision on the regulation of some types of CRISPR-Cas9 gene-edited plants. Before we get to that, could you start by explaining what led your team to start working on this issue?
It started when we received questions from two universities about whether they needed to apply for permission to undertake field trials with some plant lines modified using CRISPR/Cas9. The underlying question was whether these plants are included in the gene technology directive or not. According to the Swedish service obligation for authorities, the SBA had to deliver an answer, and thus had to interpret the directive on this point.
Could you give a brief overview of Sweden’s analysis of the current EU regulations that led to your interpretation that some CRISPR-Cas9 gene-edited plants are not covered by this legislation?
The following simplification describes our interpretation pretty well; if there is foreign DNA in the plants in question, they are regulated. If not, they are not regulated.
Our interpretation touches on issues such as what is a mutation and what is a hybrid nucleic acid. The first issue is currently under analysis in the European Court of Justice. Other ongoing initiatives in the EU may also change the interpretations we made in the future, as the directive is common for all member states in the EU.
CRISPR-Cas9 is a powerful tool that can result in plants with no trace of transgenic material, so it is impossible to tell whether a particular mutation is natural. How did this influence your interpretation?
We based our interpretation on the legal text. The fact that one cannot tell if a plant without foreign DNA is the progeny of a plant that carried foreign DNA or the result of natural mutation strengthened the position that foreign DNA in previous generations should not be an issue. It is the plant in question that should be the matter for analysis.
Does your interpretation apply to all plants generated using CRISPR-Cas9, or a subset of them?
It applies to a subset of these gene-edited plants. CRISPR/Cas9 is a tool that can be used in many different ways. Plants carrying foreign DNA are still regulated, according to our interpretation.
What does your interpretation mean for researchers working on CRISPR-Cas9, or farmers who would like to grow gene-edited crops in Sweden?
It is important to note that, with this interpretation, we don’t remove the responsibility of Swedish users to assess whether or not their specific plants are included in the EU directive. We can only tell them how we interpret the directive and what we request from the users in Sweden. Eventually I think there will be EU-wide guidelines on this matter. I should add that our interpretation is also limited to the types of CRISPR-modified plants described in the letters from the two universities.
We are currently waiting for the EU to declare whether CRISPR-Cas9 gene-edited plants will be regulated in Europe. Have policymakers in other European countries been in contact with you regarding Sweden’s decision process?
Yes, there is a clear interest; for example, Finland handled a very similar case. Other European colleagues have also shown an interest.
What message would you like plant scientists to take away from this interview? If you could help them to better understand one aspect of policymaking, what would it be?
Our interpretation is just an interpretation and as such, it is limited and can change as a result of what happens; for example, what does not require permission today may do tomorrow. Bear this in mind when planning your research and if you are unsure, it is better to ask. Moreover, even if the SBA (or your country’s equivalent) can’t request any information about the cultivation of plants that are not regulated, it is good to keep us informed.
I think it is vital that legislation meets reality for any subject. It is therefore good that pioneers drive us to deal with difficult questions.
Dr. Sarah Schmidt (@BananarootsBlog), Researcher and Science Communicator at The Sainsbury Laboratory Science. Sarah got hooked on both banana research and science writing when she joined a banana Fusarium wilt field trip in Indonesia as a Fusarium expert. She began blogging at https://bananaroots.wordpress.com and just filmed her first science video. She speaks at public events like the Pint of Science and Norwich Science Festival.
Every morning I slice a banana onto my breakfast cereal.
And I am not alone.
Every person in the UK eats, on average, 100 bananas per year.
Bananas are rich in fiber, vitamins, and minerals like potassium and magnesium. Their high carbohydrate and potassium content makes them a favorite snack for professional sports players; the sugar provides energy and the potassium protects the players from muscle fatigue. Every year, around 5000 kg of bananas are consumed by tennis players at Wimbledon.
But bananas are not only delicious snacks and handy energy kicks. For around 100 million people in Sub-Saharan Africa, bananas are staple crops vital for food security. Staple crops are those foods that constitute the dominant portion of a standard diet and supply the major daily calorie intake. In the UK, the staple crop is wheat. We eat wheat-based products for breakfast (toast, cereals), lunch (sandwich), and dinner (pasta, pizza, beer).
In Uganda, bananas are staple crops. Every Ugandan eats 240 kg bananas per year. That is around 7–8 bananas per day. Ugandans do not only eat the sweet dessert banana that we know; in the East African countries such as Kenya, Burundi, Rwanda, and Uganda, the East African Highland banana, called Matooke, is the preferred banana for cooking. Highland bananas are large and starchy, and are harvested green. They can be cooked, fried, boiled, or even brewed into beer, so have very similar uses wheat in the UK.
In West Africa and many Middle and South American countries, another cooking banana, the plantain, is cooked and fried as a staple crop.
In terms of production, the sweet dessert banana we buy in supermarkets is still the most popular. This banana variety is called Cavendish and makes up 47% of the world’s banana production, followed by Highland bananas (24%) and plantains (17%). Last year, I visited Uganda and I managed to combine the top three banana cultivars in one dish: cooked and mashed Matooke, a fried plantain and a local sweet dessert banana!
Another important banana cultivar is the sweet dessert banana cultivar Gros Michel, which constitutes 12% of the global production. Gros Michel used to be the most popular banana cultivar worldwide until an epidemic of Fusarium wilt disease devastated the banana export plantations in the so-called “banana republics” in Middle America (Panama, Honduras, Guatemala, Costa Rica) in the 1950s.
Fusarium wilt disease is caused by the soil-borne fungus Fusarium oxysporum f. sp. cubense (FOC). The fungus infects the roots of the banana plants and grows up through the water-conducting, vascular system of the plant. Eventually, this blocks the water transport of the plant and the banana plants start wilting before they can set fruits.
The Fusarium wilt epidemic in Middle America marked the rise of the Cavendish, the only cultivar that could be grown on soils infested with FOC. The fact that they are also the highest yielding banana cultivar quickly made Cavendish the most popular banana variety, both for export and for local consumption.
Currently, Fusarium wilt is once again the biggest threat to worldwide banana production. In the 1990s, a new race of Fusarium wilt – called Tropical Race 4 (TR4) – occurred in Cavendish plantations in Indonesia and Malaysia. Since then, TR4 has spread to the neighboring countries (Taiwan, the Philippines, China, and Australia), but also to distant locations such as Pakistan, Oman, Jordan, and Mozambique.
In Mozambique, the losses incurred by TR4 amounted to USD 7.5 million within just two years. Other countries suffer even more; TR4 causes annual economic losses of around USD 14 million in Malaysia, USD 121 million in Indonesia, and in Taiwan the annual losses amount to a whopping USD 253 million.
TR4 is not only diminishing harvests. It also raises the price of production, because producers have to implement expensive preventative measures and treatments of affected plantations. These preventive measures and treatments are part of the discussion at The World Banana Forum (WBF). The WBF is a permanent platform for all stakeholders of the banana supply chain, and is housed by the United Nation’s Food and Agricultural Organization (FAO). In December 2013, the WBF created a special taskforce to deal with the threat posed by TR4.
Despite its massive impact on banana production, we know very little about the pathogen that is causing Fusarium wilt disease. We don’t know how it spreads, why the new TR4 is so aggressive, or how we can stop it.
Breeding bananas is incredibly tedious, because edible cultivars are sterile and do not produce seeds. I am therefore exploring other ways to engineer resistance in banana against Fusarium wilt. As a scientist in the 2Blades group at The Sainsbury Laboratory, I am investigating how we can transfer resistance genes from other crop species into banana and, more recently, I have been investigating bacteria that are able to inhibit the growth and sporulation of F. oxysporum. These biologicals would be a fast and cost-effective way of preventing or even curing Fusarium wilt disease.