Customized Mouse Models Created Using CRISPR-Cas9

GemPharmatech constructs more than 4000 customized mouse models per year utilizing CRISPR-Cas9 technology. This construction capacity ranks among the best in the world. CRISPR-Cas9 technology is the most common gene editing technology in use today and can be used to establish knockout mice (KO), conditional knockout mice (cKO), and knockin mice (KI). 

 

Compared with other technologies, such as TALEN, ZFN, or ES, CRISPR-Cas9 is simple, fast, and low cost.

Advantages

  • High quality: Create models with no random insertions and no serial recombination 

  • High efficiency: Our platform results in a higher success rate and shorter delivery cycle than traditional methods 

  • Multi-modification: Target multiple loci, multiple genes, and large fragments 

  • Multi-background: Models can be created on a variety of genetic backgrounds, including C57BL/6J, C57BL/6N, BALB/c, FVB, NOD/LTJ, and NCG

 

Embryonic Stem Cell Homologous Recombination Technology for Creating Customized Mouse Models

Embryonic Stem Cell (ES) Homologous Recombination (HR) technology is a gene editing technique that integrates foreign DNA into the genome of ES cells. It is suitable for establishing mouse models with complex editing strategies or when the DNA inserts needed are larger than CRISPR-Cas9 technology can accommodate.

Advantages

  • Self-deletion of resistance genes can save 3 months in model generation time 

  • BAC shooting technology can achieve knock-in segments of 100-300kb 

  • Well-established technique in use since 2005 with more than 700 models successfully completed 

  • Models can be created on a variety of genetic backgrounds, including 129S6/SvEvTac and C57BL/6N 

 

Creating Customized Mouse Models Using Transgenic Technology

Transgenic technology is generally used to establish customized models for overexpressed or conditionally overexpressed mice. In transgenic technology customization, DNA is randomly integrated into the mouse genome by injecting DNA directly into a fertilized mouse egg pronucleus using microinjection technology. With the increasing efficiency of knockins (KI), most models now use the H11 or Rosa26 site for KI to create overexpressed models. 

 

Comparison of transgenic technology and KI at the H11 or Rosa26 site

Transgenic

H11/Rosa26 Knockin

F0 generation in as little as 8 weeks 

F1 generation in as little as 16 weeks 

Low technical difficulty 

High technical difficulty 

Different expression levels between founder lines, and expression levels over time (typically expression levels decrease) 

Same expression levels in all founder lines, and constant expression levels over time 

Random insertion site and number of copies 

Accurate insertion location and gene copy number by design 

Easy to alter or destroy the expression of other endogenous genes 

Does not affect expression other endogenous genes 

Poor genetic stability 

High genetic stability 

Large-scale work in establishing a stable line 

Produces a stable line directly for analysis 

 

Customized Mouse Models Using CRISPR-Cas9 Technology