Use the homologous recombination technology to replace all the exons, several important exons, or function domains of a target gene using a section of exogenous DNA sequence, and obtain a mouse model where all of the tissues and cells during all developmental stages (from 1-cell embryo to adult stage) do not express the gene.
Advantages and disadvantages:
Advantages: the design of the targeting strategy and construction of the target vector is simple
Disadvantages: the knockout of the target gene may cause embryonic death or expression dysregulation of other genes. The conditional knockout design strategy can be used if this risk is predicted to exist.
Physiological or pathological function study of a gene on the whole-body level
Drug target affirmation
Drug toxicological study
The conventional knockout realizes the target gene knockout by replacing one or more exons of the target gene using the screening gene neomycin (Neo). The knockout occurs in all of the tissues and cells in the body, which includes the risk of embryonic death. This risk can be avoided by a conditional knockout strategy. The targeting strategy is as follows: