RECOMBINANT DNA

Recombinant DNA is DNA that is artificially created from two or more sources and is incorporated into a single recombinant molecule.

Recombinant DNA (rDNA) is a form of DNA that does not exist naturally, but is created by combining DNA sequences that would not normally occur together.In terms of genetic modification, recombinant DNA is introduced through the addition of relevant DNA into an existing organismal DNA, such as the plasmids of bacteria, to code for or alter different traits for a specific purpose, such as antibiotic resistance.It differs from genetic recombination in that it does not occur through processes within the cell, but is engineered.A recombinant protein is a protein that is derived from recombinant DNA.

The recombinant DNA technique was first proposed by Peter Lobban, a graduate student, with A. Dale Kaiser at the Stanford University Department of Biochemistry. The technique was then realized by Lobban and Kaiser; Jackson, Symons and Berg; and Stanley Norman Cohen, Chang, Herbert Boyer and Helling, in 1972–74. They published their findings in papers including the 1972 paper "Biochemical Method for Inserting New Genetic Information into DNA of Simian Virus 40: Circular SV40 DNA Molecules Containing Lambda Phage Genes and the Galactose Operon of Escherichia coli", the 1973 paper "Enzymatic end-to-end joining of DNA molecules" and the 1974 paper "Construction of Biologically Functional Bacterial Plasmids in vitro",all of which described techniques to isolate and amplify genes or DNA segments and insert them into another cell with precision, creating a transgenic bacterium. Recombinant DNA technology was made possible by the discovery, isolation and application of restriction endonucleases by Werner Arber, Daniel Nathans, and Hamilton Smith, for which they received the 1978 Nobel Prize in Medicine. Cohen and Boyer applied for a patent on the Process for producing biologically functional molecular chimeras which could not exist in nature in 1974. The patent was granted in 1980