The assigned MMRRC Center can accept a mouse strain as either live mice, cryopreserved material, and/or ES cells.

• Live Mice:

  Transfer of live mice to the MMRRC is preferred. Please contact your strain’s assigned center to coordinate the transfer of mice. Mice should be of suitable breeding age.

• Cryopreserved Material:

  The MMRRC facilities can also accept previously cryopreserved embryos and spermatozoa. The Submitting Investigator must coordinate with the assigned MMRRC Center prior to transfer of cryopreserved material. Please note that there is always a risk of failure to resuscitate a strain if only cryopreserved material is submitted. Therefore, the MMRRC cannot assure recoverability of a strain until it is successfully resuscitated to fertilized embryos or live mice.

• Embryonic Stem Cells (ES Cells):

  The MMRRC will accept gene-targeted ES cells that can be microinjected into blastocysts to generate live mice. Submitters should ensure they provide detailed information on the ES cell (origin of the line, gene-targeting method, passage number since electroporation, genotyping confirmation of integration of the inserted allele, PCR protocol to confirm identity and homologous recombination (if relevant) of the inserted allele, nucleotide sequence of inserted allele, microinjection protocol, germline transmission information (if performed)). The Submitting Investigator must coordinate with the assigned MMRRC Center prior to transfer of cryopreserved ES cells. Please note that there is always a risk of failure to convert ES cells to live mice and germline transmission of the inserted allele if only cryopreserved ES cells are submitted. Therefore, the MMRRC cannot assure conversion of ES cells to live, germline transmitted mice until they are successfully microinjected to produce chimeras and bred for germline transmission.

The assigned MMRRC Center will work with the Submitting Investigator to coordinate the transfer process.