Welcome to the Mutant Mouse Regional Resource Centers (MMRRC) Web site.

    The MMRRC distributes and cryopreserves scientifically valuable, genetically engineered mouse strains and mouse ES cell lines with potential value for the genetics and biomedical research community. We are a national network of breeding and distribution facilities plus an information coordinating center serving together as NIH's premier repository of spontaneous and induced mutant mouse and cell lines. The MMRRC is supported by the National Center for Research Resources at the National Institutes of Health.

   Strains of mice are maintained in a cryopreserved state unless demand warrants that a live colony be established. Live mice are supplied from a production colony, from a colony recovered from cryopreservation, or via micro-injection of a cell line into host blastocysts. At its option, an MMRRC facility may offer cryopreserved material for resuscitation at the recipient scientist's institution. The MMRRC charges fees to partially cover repository costs; please see our Fees page for details.