The MMRRC Distribution Centers accept strains in the following formats: live mice*, cryopreserved germplasm, embryonic stem (ES) cells, mouse induced pluripotent stem cells (miPSCs), human induced pluripotent stem cells (hiPSCs), hybridoma cells, and tissues (fixed, frozen, or paraffin-embedded blocks).

The Submitting Investigator (SI) is responsible for ensuring that all submitted materials meet MMRRC material requirements prior to shipment. See the MMRRC Submission Material Requirements section below for more information.

* Live mice are the preferred submission material.

Live Mice: Live mice submitted to the MMRRC are expected to be viable, healthy, disease-free, and harbor the intended allele(s) as described in the submission application.

• Mice should be of suitable breeding age. Contact your assigned center for more details.

Cryopreserved Germplasm: Cryopreserved germplasm (embryos and sperm) is expected to be viable, cryo-recoverable, and express the intended allele(s) as described in the submission application.

• Cryopreserved materials can sometimes fail resuscitation. The MMRRC cannot ensure recoverability of cryopreserved germplasm until material is successfully resuscitated to fertilized embryos or live mice.

ES cells, miPSCs, and hiPSCs: Cryopreserved stem cells must be viable, culturable, mycoplasma and other pathogen free, and express the intended allele(s) as described in the submission application.

• Conversion of ES cells to live, high-percentage chimeras can sometimes fail and germline transmission (GLT) of the targeted allele is not guaranteed. GLT can only be confirmed after successful microinjections, birth of chimeras, cross-breeding with wildtype control mice, and genetic testing of offspring. Genomic and epigenetic stabiligy, reprogramming, and differentiation efficiency cannot be guaranteed when using miPSCs or hiPSCs. Contact your assigned center for more information.

Hybridoma cells: Cryopreserved hybridoma cells must be viable, culturable, mycoplasma and other pathogen free, and express the intended antibodies as described in the submission application.

Tissues: Tissues must be of sufficient quality and appropriately identified to ensure they are associated with the intended mouse line(s) as described in the submission application.

Following acceptance of a strain application by the MMRRC Consortium Coordinating Committee, the SI may change the material type (e.g., live mice, cryopreserved germplasm, etc.) they intend to ship to the assigned MMRRC Distribution Center. The SI must notify the assigned Center of any such change.

The SI must not initiate shipment until the assigned Center confirms and accepts the change in format of the materials to be shipped.