Author
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Ow, David |
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Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 1/1/2002 Publication Date: 1/1/2002 Citation: OW, D.W. SITE-SPECIFIC GENE STACKING METHOD. In: PLANT BIOTECHNOLOGY 2002 AND BEYOND. Vasil, I.K., editor. Kluwer Academic Press, Dordrecht. BOOK CHAPTER. 2003. p. 215-218 Interpretive Summary: Technical Abstract: Recombinase-mediated gene targeting has been achieved in a number of plant species (for review, see Ow, 2002). The general scheme requires a first recombination site to be introduced into the genome to serve as the target site for the subsequent insertion of a second DNA molecule. With plants, a current limitation is that the target site can only be generated at random chromosome locations. Reports to date show that recombinase-directed site-specific integration can place a single-copy non-rearranged DNA fragment into the target site at a practical frequency. Moreover, a high percentage of the insertions express the transgene at a predictable and reproducible level (Day et al., 2000). This means that once a suitable target line is found, it can be used for the subsequent delivery of trait genes. However, the current methods do not provide a convenient way to append additional trangenes to the target locus once the first insertion event is obtained. In this paper, a strategy is described that permits the sequential and repeated delivery of new DNA to the genomic target, as might be expected if a transgenic plant line were to be improved over time through the sequential addition of new transgenic traits. Appending DNA onto existing target sites justifies the initial investment in screening for suitable chromosome locations. The clustering of desirable traits also facilitates the introgression of large gene sets to field cultivars. |
