Floxing

In genetic engineering, floxing refers to the insertion of a DNA sequence (which is then said to be floxed) between two LoxP sequences, creating an artificial gene cassette which can then be conditionally deleted (knocked out), translocated, or inverted in a process called Cre-Lox recombination. Recombination between LoxP sites is catalysed by Cre recombinase. The term "floxing" is a portmanteau constructed from the phrase "flanking/flanked by LoxP".

The floxing method is essential in the development of scientific model systems as it allows researchers to have spatial and temporal alteration of gene expression. The Cre-Lox system is widely used to manipulate gene expression in model organisms such as mice in order to study human diseases and drug development. For example, using the Cre-Lox system, researchers are able to study oncogenes and tumor suppressor genes and their role in the development and progression of cancer in mouse models.