Skip to main content

gene cloning

gene cloning (DNA cloning) The production of exact copies (clones) of a particular gene or DNA sequence using genetic engineering techniques. The DNA containing the target gene(s) is split into fragments using restriction enzymes. These fragments are then inserted into cloning vectors, such as bacterial plasmids or bacteriophages, which transfer the recombinant DNA to suitable host cells, such as the bacterium E. coli. Alternatively, complementary DNA is inserted into the vectors, or ‘naked’ DNA fragments can be taken up directly by a host bacterium from its medium (this is less efficient than vector transfer).

Inside the host cell the recombinant DNA undergoes replication; thus, a bacterial host will give rise to a colony of cells containing the cloned target gene. Various screening methods may be used to identify such colonies, enabling them to be selected and cultured. Gene cloning facilitates DNA sequencing; it also enables large quantities of a desired protein product to be produced (see expression vector): human insulin, for example, is now produced by bacteria containing the cloned insulin gene. See also positional cloning.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"gene cloning." A Dictionary of Biology. . 19 Jul. 2019 <>.

"gene cloning." A Dictionary of Biology. . (July 19, 2019).

"gene cloning." A Dictionary of Biology. . Retrieved July 19, 2019 from

Learn more about citation styles

Citation styles gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, cannot guarantee each citation it generates. Therefore, it’s best to use citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

The Chicago Manual of Style

American Psychological Association

  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.