Targeted gene knockouts in crops using RNA-guided Cas9 nuclease

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In developing improved crops, plant breeders have always depended on finding variation or changes within a population to identify characteristics (or genetic traits) that could potentially offer an advantage to the crop. This variation is due to changes that can occur in the genetic sequence (DNA) of the crop plant over time - and is a normal part of evolution (mutations in the DNA). These changes can be responsible for many new characteristics such as plants with increased disease resistance or improved nutritional quality. Sometimes the desired variation is not available so breeders have used methods to introduce changes in the DNA such as chemical or radiation treatment of seed hoping to find the required variation in the resulting plants. These methods have been widely used in conventional plant breeding for decades. Changes to the DNA sequence often leads to a mutation that stops a particular gene from working. Mutations are incredibly useful as research tools as well as useful to plant breeders. If a scientist can find a mutation in the gene that they are interest in (i.e. generating a non-functional gene, or a gene knock-out) then they have a way of working out what that gene does.Until recently, methods to introduce mutations were non-specific meaning they could target a large number of genes within the plant, hopefully including the DNA region, or gene, of interest. Now for the first time we have a technology to introduce mutations into a specific gene of interest. This is referred to as genome editing. A specific genome editing technology called CRISPR / Cas9 allows easy targeting of any gene of interest and we have demonstrated that this works well in both barley and Brassica oleracea (broccoli). In this project, we will offer to create plants with mutations in specific gene(s) of interest for the research community. This will allow more rapid progress in a range of research programmes. In addition, the resource we will offer could lead to plants with desirable characteristics to include in new crop varieties. As this technique is very new there have not yet been decisions as to how it should be regulated. The data that we will collect in this project will also help regulators to make decisions on future regulation of genome editing.