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updated: June 24, 2024


Cloning, as it relates to genetics and genomics, involves using scientific methods to make identical, or virtually identical, copies of an organism, cell or DNA sequence. The phrase “molecular cloning” typically refers to isolating and copying a particular DNA segment of interest for further study.



Cloning. Cloning is a word we use to describe a laboratory process of making millions or even billions of copies of a single molecule, most often DNA. It's different from the uses of the term cellular cloning or organism cloning that are used in reproductive genetics. We use molecular cloning to amplify or make many copies of DNA, which allows us to study the molecules in the laboratory. And to perform genetic tests on small samples of blood, saliva, or other tissues from patients.

Leslie Biesecker
Leslie G. Biesecker, M.D.

Director & NIH Distinguished Investigator

Center for Precision Health Research