Knockin Mouse Models

Customized Mouse Models

A Knockin mouse defines an animal model in which a gene sequence of interest is altered by one-for-one substitution with a transgene, or by adding gene sequences that are not found within the locus.

The insertion of a transgene is typically done in specific loci. This "targeted" approach causes less disturbances of the transcription-active genetic environment. 

Knockin mice are suited to a wide range of application, from the study of regulatory elements such as promotors to the production of therapeutically useful humanized antibodies.


Our Knockin mouse model solutions

Besides conventional Knockins where a gene sequence of interest is added to an endogenous locus, we offer a set of commonly used solutions:

  • Reporter mouse
    Monitor genetic events, protein function, localization, and cell trafficking


Conditional activation of gene insertions or substitutions

All Knockin designs can bear conditions that allow your gene insertion or substitution to be activated: A) in specific cell types in a certain tissue while other cell types and tissues exhibit an unmodified, functional gene expression, and/or B) temporally at a given time-point in embryonic, post-natal or adult animals.

Two common approaches are typically used:


The Cre recombinase recognizes the loci of recombination loxP that causes a deletion of the STOP sequence between the two loxP sites, allowing the transcription of your mutation gene of interest.

Infographic: lox-STOP-lox


Both loxP and lox511 are recognized by Cre recombinase but lox511 sites can only recombine with other lox511 sites, not with loxP sites.

When the DNA sequence is flanked by lox sites in opposing orientations, the Cre will invert the sequence between the sites. If the DNA sequence is flanked by lox sites in the same orientation, the Cre will excise the sequence.

By combining type of lox sites, number, and orientation of lox sites that surround your genes of interest, a powerful FLEx tool can be created for your specific scientific needs.

As for the lox-STOP-lox approach, expressing the Cre recombinase in a specific cell type or tissue leads to a tissue-specific mutated gene expression, and using an inducer-activated Cre recombinase leads to a temporally mutated gene expression in the presence of an inducer such as tamoxifen. 

Infographic: FLEx



Learn more about our customized mouse model service:

Customized Mouse Model Catalog


Follow this link if you are looking for another customized mouse model or transgenic model.