About one billion people in the world struggle to get enough vitamin D. Deficiency can lead to lethargy and disease. Some people experience sore and sore muscles, and in the worst case, you can develop osteoporosis. The most important source of vitamin D is sunlight, something we northerners do not have too much of. But you can also get the much needed nutrition through oily fish and margarine. Now British researchers may have found another solution, which is even plant-based. They have managed to re-edit tomatoes to contain a large dose of the important vitamin. – 40 percent of people living in Europe have vitamin D deficiency. We not only address a major health problem, but also help manufacturers. For tomato plants that today go in the trash, this method can rather be used to make supplements. This is what Professor Cathie Martin says in a press release. The new study is published in the journal Nature Plants. CRISPR CRISPR (Clustered Regularly Interspaced Short Palendromic Repeats) is a gene editing method that makes it possible to make targeted changes in the DNA of all living organisms. CRISPR can be compared to finding and cutting out a particular word or phrase from a document, and, if desired, replacing it with a new word. CRISPR can be used to fix pathogenic mutations in humans, achieve new properties in crops and construct new microorganisms. CRISPR consists of two components that work together; a “gene shear” – an enzyme (usually Cas9) that can cut DNA – and a “GPS” – a special RNA molecule (called sgRNA) that directs the enzyme to the right place in the DNA by binding to a matching sequence. By changing the RNA sequence, one can thus decide where the DNA is to be cut. The rest of the work is done by the cell itself. When a cut in the DNA is detected, the cell implements systems to repair it. By manipulating this process, one can remove, replace or add DNA to the cut zone, for example, replacing a pathogenic mutation with a healthy DNA sequence. Source: Large medical encyclopedia Plant-based and sustainable? It is with the help of CRISPR technology that researchers have been able to make changes to the tomatoes’ genetic codes. In this way, the vegetable has been able to collect provitamin D3. This is converted to vitamin D as the plant is exposed to UVB light. These “new” tomatoes can contain as much vitamin D as you find in two eggs, or in a tablespoon of tuna. According to the researchers, no differences could be seen between the common and the genetically modified plants. The study also shows that the amount of vitamin can be increased if you use more UVB light. – Now we have shown that gene editing means that tomatoes can be developed to become a plant-based and sustainable source of vitamin D3, says Martin. Nobel Prize in Chemistry In 2020, Emmanuelle Charpentier and Jennifer A. Doudna received the Nobel Prize in Chemistry for the development of the gene editing tool CRISPR. The technology has already gained great importance in research and development. And many believe that it will, among other things, change the way we produce food in the future. In the right hand you will find a genre-edited tomato. In the left is a common type. Photo: John Innes Center Stine Hufthammer Indrelid is a cell biologist. She works for the Biotechnology Council in Norway. She says the new study is part of a trend. – In recent years, we have seen several examples of gene editing being used to create food plants with alleged health benefits. This can be so-called functional food with an increased content of substances that are claimed to have different effects on health, or with a reduced content of substances that are harmful to health, she writes in an e-mail to news. As of today, there are no genetically modified foods in Norwegian stores. But the cell biologist thinks something is about to happen. – Considering the great development that is taking place in this field, it may not be long before Norway also has to consider applications to approve genetically modified food plants. Only then do we get the answer to whether such tomatoes with vitamin D are considered to be socially beneficial and sustainable. In addition, the ethical discussion around genetically modified food is important, Indrelid explains. – On the market in a short time CRISPR has also been used in this country. One of those working on this is Tage Thorstensen. He is a researcher at NIBIO. Here, CRISPR has been used to create mutations in genes that are thought to make iceberg lettuce and wild strawberries vulnerable to fungal disease. Thorstensen thinks the new research on tomatoes is exciting. – I think this is a good piece of work. It shows that one can use the technology to make a small mutation in an enzyme so that the plants accumulate provitamin D instead of converting it into cholesterol. They did this without inserting foreign DNA. Thus, these are mutations that could have occurred naturally, the Norwegian researcher explains. Tage Thorstensen believes a lot will happen in this area in the time ahead. In the UK, there is a good chance that you will make a change in the law that will allow plants without foreign DNA. The EU is also considering a relaxation of the regulations for the use of CRISPR plants. – I am optimistic and hope we will get such plants on the market in the EU, and hopefully in Norway as well, soon. Something else will be in spite of the recommendations from, so to speak, a cohesive, international research environment. Tage Thorstensen is a researcher at NIBIO. He believes that CRISPR technology has an almost unlimited potential for improving plants if you know the gene sequence and the biochemical processes you want to change. Photo: Erling Fløistad / NIBIO
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Researchers have used CRISPR to re-edit tomatoes – contains as much vitamin D as two eggs – news Trøndelag
