Gene Editing and Genetic Transformation of Potatoes

Gene editing and genetic transformation are alternatives to sexual hybridization for potato improvement. Engineered nucleases catalyse a double-stranded DNA break at a specific location in the genome so that desired DNA modifications can occur at the break site rather than at random. TALENS and CRISPR-Cas9 can be designed to target all four alleles of a gene in tetraploid potato and hence achieve a knock-out mutation, but more research is required to create and fix novel alleles. Agrobacterium-mediated transformation is now free of selectable markers, and currently up to eight transgenes are being stacked. Potatoes have been transformed for improved disease and pest resistance, processing quality and nutritional value. Transgene-mediated post-transcriptional gene silencing through RNA interference has provided a number of desirable phenotypes by inactivating one or several specific genes. The reluctance to accept genetically modified potatoes is considered along with the GM regulations in the European Union and the USA.