Gene Editing Services 

GEMM has extensive experience with the design of mice using engineered nucleases such as ZFNs, TALENs, and CRISPR/Cas9, with the vast majority of our projects using CRISPR/Cas9. 

 Common types of genetic modifications introduced by engineered nucleases like CRISPR/Cas9 include:

• deletions to generate knockout mice,
• small changes in DNA composition to introduce SNPs,
• the introduction of small molecular tags, including loxp sites.  This can enable the tagging of a gene of interest or the generation of conditional knockout mice.

  Less common requests include larger insertion and replacement events. 

 We frequently combine the CRISPR/Cas9 technology with IVF to enable genetic engineering directly in a wide range of background strains, including B6J, B6N, NOD, FVB, already genetically modified mice and others.  Please inquire.

 The general workflow for creating a gene edited mouse is as follows: 

1. Consultation- meet to discuss project goals.
2. gRNA design- with information provided by the investigator, GEMM will design and generate CRISPR reagents for the production of mouse models or for investigator led efforts to modify cell lines.
   • Simple- includes design of gRNA to drive a single dsDNA break for the introduction of SNPs, small tag knockins.
   • Complex- includes the design of gRNA for dsDNA breaks at two locations in the genome, as necessary for conditional gene knockouts.
3. gRNA activity testing- GEMM will test guide activity in vitro or in embryos cultured to blastocysts.
4. HDR template design and synthesis- GEMM will design HDR templates, synthesize and prepare them for use.  This may include ssODNs, long ssDNA, and the generation of AAV to deliver the desired HDR template.
5. Microinjection or electroporation- GEMM will generate embryos by natural mating or by IVF, introduce gene editing reagents, and perform embryo transfers.
6. Resulting pups will be genotyped to identify putative founders.  Mice can be transferred to researcher at this stage or kept in our breeding program to establish germline transmission.