Researchers at UC Davis have discovered methods of selecting plants with targeted genome edits without resorting to tissue culture or selectable transgenes. The resulting method is a non-transgenic approach that avoids the off-target background mutations generated by selection in tissue culture.
Technologies based on genome editing proteins, such as CRISPR-Cas9, zinc finger nucleases, and TALENs, are rapidly advancing, allowing researchers to efficiently target genetic changes to specific DNA sequences. In most plants, however, it is currently necessary to go through tissue culture to obtain modifications of the germline; tissue culture is time consuming and frequently mutagenic increasing the cost and the likelihood of introducing unpredictable and off-target mutations in addition to the desired changes. As a result of these shortcomings, a method is desired that does not require going through tissue culture and allows the selection of modified cells without the use of resistance genes.
Researchers at the University of California, Davis have developed a method for selecting modified plants using co-transformed genes to enable controlled germination only for successfully edited cells, obviating the need for traditional tissue culture. As a result, alleles can be introduced into well adapted genotypes without background mutations. Using this method, genome edits can be selected with greatly reduced risk of unpredictable and undesired mutations.