ABSTRACT
Most agronomic traits controlled by breeding are quantitatively inherited, being controlled by many genes, and strongly environmentally influenced. Therefore, new breeding technologies that can introduce one or a few traits into an elite background would appear useful for developing new cultivars. In this study, the foreign DNA is recombined within overlapping parts of the protein-coding region, resulting in the formation of an active gene in the host chromosome after transformation. If the targeted site is in the coding region, the introduced indels frequently generate frameshifts, resulting in gene disruption. In addition, the genetic elements required for genome editing, such as Cas9 and sgRNAs, can be removed from the genome through genetic crosses or following segregation in the progeny, which makes genome-edited plants free of exogenous DNA, and the mutations were stable inheritable. Precise genome modification such as knock-in and gene replacement via homologous recombination (HR) is a powerful tool and widely used in many organisms.
