Establishment of a CRISPR-Cas9-Mediated Genome Editing System in Flax

Flax is an important crop used for oil and fiber production. Although genetic engineering has been possible in flax, it is not commonly used to produce cultivars. However, the use of genome editing technology, which can produce site-specific mutations without introducing foreign genes, may be a valuable tool for creating elite cultivars that can be easily cultivated. The purpose of this study was to investigate the potential of genome editing in flax by establishing the clustered regularly interspaced short palindromic repeats (CR ISPR)-CRISPR-associated protein 9 (CRISPR-Cas9) genome editing system using the phytoene desaturase (PDS) gene, which produces albino mutants that are easily identifiable. Four sgRNAs were designed from two PDS genes of Flax (LuPDS1 and LuPDS2), and CRISPR-Cas9 genome editing vectors were constructed. After gene transformation, albino phenotypes were observed in transformed callus and regenerated plantlets on selection media. Polymerase chain reaction (PCR) amplification and sequencing of the PDS genes revealed deletions and insertions in the albino tissues, indicating successful editing of the PDS genes. Potential off-target sites were analyzed, but no off-target mutations were found, indicating the specificity of the CRISPR-Cas9 system. The establishment of a flax genome editing system using the CRISPR-Cas9 technology opens up new possibilities for the genetic engineering of flax. This study demonstrates the potential of genome editing in creating elite cultivars that can be easily cultivated, which can have significant implications for the flax industry.