Phenotyping of Genetically Engineered Rodents

The overall goal of rodent phenotyping is to facilitate the discovery of novel animal models for the study of disease and basic biologic processes.

Genetically engineered rodents have emerged as preeminent animal models for the study of human disease and basic biological processes. Thousands of models have been generated to date and with the recent advances in genetic engineering technology, the expansion of functional genomics and proteomics, and the application of genetic engineering techniques to species other than the mouse, the number of genetically engineered rodents will surely grow. While gene manipulation often results in expected phenotypes, it has been suggested that over 50% of phenotypes are unanticipated. Unfortunately, most scientists do not have the time or resources to thoroughly characterize mutant rodents beyond the needs of their individual laboratories. Mutant rodents with no readily apparent phenotypes and those with unwanted phenotypes may be discarded. Moreover, those rodents with documented phenotypes may have other phenotypes that have not been recognized. As a result, the potential of many genetically engineered rodents as models for disease may not be fully recognized. To address this, we provide baseline phenotyping of genetically engineered rodent models with the major goals being to discover and characterize novel phenotypes and to disseminate information about these models on a searchable web database.

Baseline phenotyping includes thorough gross and histomorphologic examination, hematology, clinical chemistry and behavioral analyses. Additional examinations may be employed in some cases where indicated by reported phenotypes of data from baseline screens.

While it is recommended to test a minimum of 3 mice per sex, genotype and age, this is not always feasible due to low animal numbers, the expense of mutant rodents, etc. Tiered approaches (i.e. testing of one mutant and one control mice) are often employed to generate initial observations that can be confirmed by more limited testing of additional mice. As a result, data included for some lines is preliminary and should be interpreted with appropriate caution.

Contacts for rodent phenotyping: