Patent ID: 7820880

Claim:
A method for stacking multiple polynucleotides at a specific chromosomal site in a plant genome comprising: a. providing a plant cell having stably incorporated into its genome a first polynucleotide comprising at least one expression cassette of interest adjacent to a target site, wherein said target site is flanked by a first non-identical recombination site and a second non-identical recombination site; b. introducing into the plant cell a transfer cassette, wherein said transfer cassette comprises a second polynucleotide comprising a nucleotide sequence of interest flanked by the first non-identical recombination site and the second non-identical recombination site, wherein said first and said second non-identical recombination sites can recombine with their identical site; and, c. providing a recombinase that recognizes and implements recombination at the non-identical recombination sites, and thereby allow for the directional targeting of the nucleotide sequence of interest at the target site.