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updated: May 21, 2024


A knockout, as related to genomics, refers to the use of genetic engineering to inactivate or remove one or more specific genes from an organism. Scientists create knockout organisms to study the impact of removing a gene from an organism, which often allows them to then learn something about that gene’s function.



Knockout. When I think of knockout, I think of being able to knock out an assignment on my list of tasks. That is to completely finish it and remove it from my list. That's not unlike what we mean when we refer to a gene knockout, where the goal is to make a gene completely nonfunctional. The simplest way to create a complete gene knockout is to remove the entire region of the gene by cutting it out and then seeing how that affects the organism after removal. This is where the term gene knockout or something like a knockout [inaudible] comes in. This is, however, not the only way to create one, but it's the most complete method. Other ways include changing regions of the gene that are suspected to be important for function. This second method is not always guaranteed to completely interrupt gene function.

Stephanie Morris
Stephanie A. Morris, Ph.D.

Program Director

Division of Genome Sciences