Hybrid plaanid DN\ purified, treated with a second restriction enzyme 
that acts at two sites (Y) within the unwanted gene. 
Ligation then ties together the two new ends leaving out the unwanted 
segment. 
This reconstructed hybrid plasmid is then re-transferred to E. coli 
for anplif i cation, then re-introduced into parent organism, in vbich it 
cannot nultiply on its own. 
Recombinant DNA Research, Volume 1 1 
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