Science 15

Genetic recombination is the combining of DNA from one organism with the DNA of another. The experiments below describe how scientists recombined bacterial and mammalian DNA.

Experiment 1

Bacteria contain plasmids, rings of DNA that can be removed and used in genetic recombination. Plasmids are cut open using restriction enzymes. Each restriction enzyme cuts DNA when it encounters an enzyme-specific sequence within the DNA. Researchers tried various restriction enzymes on an E. coli bacterial plasmid. The results are shown in Table 1.

Experiment 2

Researchers inserted a gene that coded for a certain blood protein found in mammals into the bacterial plasmid. The bacterial plasmid DNA sequence is shown in Figure 1. Researchers used a restriction enzyme that cut at “ACGACG” to open the plasmid and insert the mammalian gene.