Recombinant DNA is a form of artificial DNA which is engineered through the combination or insertion of one or more DNA strands, thereby combining DNA sequences which would not normally occur together.[1] In terms of genetic modification, recombinant DNA is produced through the addition of relevant DNA into an existing organismal genome, such as the plasmid of bacteria, to code for or alter different traits for a specific purpose, such as immunity.It differs from genetic recombination, in that it does not occur through processes within the cell or ribosome, but is exclusively engineered.The Recombinant DNA technique was engineered by Stanley Norman Cohen and Herbert Boyer in 1973. They published their findings in a 1974 paper entitled "Construction of Biologically Functional Bacterial Plasmids in vitro", which described a technique 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 of restriction endonucleases by Werner Arber, Daniel Nathans, and Hamilton Smith, for which they received the 1978 Nobel Prize in Medicine.
Genetic engineering, recombinant DNA technology, genetic modification/manipulation and gene splicing are terms that are applied to the manipulation of genes, generally implying that the process is outside the organism's natural reproductive process. It involves the isolation, manipulation and reintroduction of DNA into cells or model organisms, usually to express a protein. The aim is to introduce new characteristics or attributes physiologically or physically, such as making a crop resistant to a herbicide, introducing a novel trait, enhancing existing ones, or producing a new protein or enzyme. Successful endeavours include the manufacture of human insulin through the use of modified bacteria, the manufacture of erythropoietin in Chinese hamster ovary cells, and the production of new types of experimental mice such as the OncoMouse for research.Since a protein sequence is specified by a segment of DNA called a gene, novel versions of that protein can be produced by changing the DNA sequence of the gene. There are a number of ways through which this could be achieved. After isolating a section of DNA that includes the gene, the gene or required portion of the gene is cut out. After modification of the sequence if necessary, it may be introduced into a different DNA segment or into a vector for transformation into living cells. Daniel Nathans and Hamilton Smith received the 1978 Nobel Prize in Physiology or Medicine for their isolation of restriction endonucleases, which are able to cut DNA at specific sites. Together with ligase, which can join fragments of DNA together, restriction enzymes formed the initial basis of recombinant DNA technology. Some groups have argued[citation needed] that genetic engineering is wrong and is "doing the work of God", but most scientists believe that genetic engineering is essential to help future medical discoveries. However, even with regard to this technology's great potential, scientists around the world have raised concerns about the introduction of genetically engineered plants and animals into the environment and the potential dangers of human consumption of GM foods. They say that these organisms have the potential to spread their modified genes into native populations thereby disrupting natural ecosystems. See also GM Food Controversies, and Genetically modified organism for more information on controversies. Professor Stephen Hawking defended the genetic enhancing of our species in order to compete with Artificial intelligence.