Developed in 1983 by kary mullis revolutionised molecular biology and molecular cloning exponential copying of few dna molecules into thousands millions of copies. Pcr: in vitro amplification of a dna sequence. Copy single molecule of dna into a few thousands using temperature modulation. Utilizes melting and annealing properties of dna hybridization . Pcr relies on thermal cycling (i. e. heating and cooling of reaction) Requires some knowledge of the sequence of the gene of interest. Provides an efficient alternative strategy to traditional cloning method. Sequence specific primers - hybridize to complementary dna. Traditional - large genomic dna cut with re, southern blotting and probe. To find which piece contain our gene of interest. Design primers that contain specific restriction enzyme sites (@5" end of primer) Amplify a piece of dna and incorporate these restriction sites which we can then specifically and directly digest our amplify dna. Ligate digested amplified dna into plasmid vector.
