All animal handlings (mouse selection,set-up of matings, hormone injections) necessary for these procedures are performed by the Microinjection Team.
A purified genetically engineered DNA is injected into the pronuclei of a fertilized mouse eggs. These injected eggs are then surgically implanted into a pseudopregnant female to produce mice harboring the transgene. Pups are screened for the presence of a transgene at 10-12 days of age. Transgenic founders are identified by PCR genotyping or characterized on request by the gene expression service. Additional breedings to establish the transgenic lines can be proposed.
Targeted ES cell clones are injected into blastocysts to produce chimera mice. These microinjected embryos are transferred into pseudopregnant recipients. Litters are monitored and evaluated for coat color chimerism. Male chimeras with moderate and high ES cell contribution are then tested for germline transmission. Alternatively, chimeras can be transferred to the investigator after weaning.