CRISPR Service

The Genome Editing Core offers CRISPR/Cas9 nuclease services for production of mutant mice by pronuclear and/or cytoplasmic injection and/or electroporation. This technology allows production of genetically modified mice in as little as 3-4 months. Many kinds of mutations can be introduced, including point mutations such as SNPs, LoxP sites, reporter genes, protein tags, deletions, etc. Genetic modification can eliminate the need for manipulation in ES cells. Contact the core director, William Paradee, to see if CRISPR/Cas9 technology can be used for your project.

Embryo Cryopreservation Service
picture of white mouse

Cryopreservation of embryos is an ideal solution to maintain a live animal colony for strains that are rarely used. Homozygous, inbred, or complex strains are typically frozen as embryos to preserve the entire genome.  As when freezing sperm and only half the genome. This backup can save significant space and prevent loss due to disease or in case an issue arises within your animal facility, providing an alternative to manage the colonies that will be used for research.

Procedures for embryo cryopreservation include superovulation of embryo donors (generally, female mice aged 3-4 weeks of the same background as the embryo donors.), mating of superovulated females to male mice, collection of two-cell embryos, cryopreservation of two-cell embryos, quality control throughout cryopreservation process and storage in liquid nitrogen.

The core can back up your live animal colony by our embryo cryopreservation services, which can not only protect your valuable strains but also reduce your cost in the long run. We also can produce live animals for you in eight to twelve weeks once your cryopreserved stock is preserved. Please contact our cryopreservation specialist JoAnn Schwarting for more information.

Embryo Derivation Services

The Genome Editing Facility does provide "mouse rederivation services" or more accurately mouse derivation via embryo transfer. This process involves the mating of infected males with clean female mice. The next day before any infection can become  full blown, the fertilized embryos are harvested and washed 12 times by very carefully moving the embryos through wash medium with the minimum of  transferred medium.  These washed embryos are implanted into an specific pathogen free (SPF) or clean foster mother to be brought to term. At weaning, the embryo derived pups are tail tipped and their genotype is determined via PCR. Founders are then determined. At least one non founder pup per litter and the mothers are kept until the embryo derived pups are 2 months of age to provide ample time for infection from the mother and to raise anti-pathogen antibody titers.  The mother along with a non founder pup are submitted to animal pathology for a serology panel and PCR analysis for pathogens. Those mice determined to have a (SPF) status are then released to the investigator. Any infected pups (very rare) will be euthanized. 

Embryo Thaw and Reanimation Services 

Fertilized preimplantation embryos frozen in liquid nitrogen will be thawed using protocols accompanying the embryos and all recovered embryos implanted into pseudo pregnant recipient females in order to reanimate a mouse line. Assess the embryos for viability prior to implantation. PCR genotyping is available upon request at an additional charge. 

In Vitro Fertilization Service
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The investigator is responsible for providing cryopreserved mouse germplasm to the Genome Editing Core. Oocytes will be isolated from C57BL/6J mice. Alternate strains may be used for an additional fee.  Oocytes will be isolated and fertilized in vitro using the investigator-provided germplasm. Two-cell stage embryos will be implanted into recipient females for gestation. Resulting pups will be weaned and transferred back to the investigator after the health screen (at cost to the investigator). 

Mouse Colony Genotyping

To request service for Mouse Colony Genotyping, please contact Facility Director William Paradee.

Mouse Colony Maintenance

To request service for Mouse Colony Maintenance, please contact Facility Director William Paradee.

Pronuclear Injection Service

The Core offers pronuclear injection for basic transgenic mouse production.  With this service the DNA for injection is digested out of the plasmid, gel purified, and dialyzed to remove impurities.  The DNA is injected into the C57BL/6 embryo pronuclei.  Screening by PCR will be used to identify founder pups. Learn more.

Sperm Cryopreservation Service

Sperm cryopreservation is a procedure whereby sperm is harvested usually from experienced two male donors (aged 10-16 weeks old). The samples are then placed in specialized freezing solution, drawn up into labeled freezing straws and methodically frozen. This is an ideal method to archive highly valuable mouse lines thereby isolating them from some unforeseen problem in animal care like a parvovirus outbreak, from severe storm damage, a protracted disruption of utilities such as electricity or water supply or an unexpected loss of funding. Frozen sperm samples can be used to rapidly rebuild a mouse colony. Reanimation of cryo preserved mouse lines can be accomplished by in vitro fertilization. To get started download a service request form and follow the direction.