Overview
Understanding what a gene does often begins with seeing what happens when it's missing. Knockout (KO) mouse models are among the most fundamental tools in biomedical research, allowing scientists to eliminate a gene's function and observe the resulting effects on physiology, behavior, and disease development.
What Is a Knockout Mouse?
A knockout mouse is a genetically engineered organism in which a target gene has been permanently disrupted or deleted in every cell of the body. This is typically achieved by replacing part or all of the gene's coding sequence with a nonfunctional segment of DNA during homologous recombination gene targeting.
Types of Knockout Models
Constitutive (conventional) knockouts permanently inactivate the gene in all tissues throughout life. Conditional knockouts (cKO) use site-specific recombination (e.g., Cre-lox) to inactivate the gene only in specific tissues or at specific developmental stages.
Frequently Asked Questions
What's the difference between a knockout and a knockdown model?
A knockout completely eliminates gene function through targeted deletion or disruption, while a knockdown model reduces gene expression without fully abolishing it.