Genetic factors are important in model selection in several respects. The species selected should have a well known background, since some species may develop naturally occurring genetic diseases or conditions which can provide useful spontaneous models. In research areas where no spontaneous animal model has been identified, extensive knowledge of a species' genetic properties is essential to selection of a likely candidate for an induced model.
In some common laboratory species, mutant or inbred strains have been developed with well documented and often highly specific genetic properties. Catalogues and bibliographies of such models provide a useful source of information for researchers (e.g., the NIH Rodent Catalog, Hegreberg and Leathers, 1982 a, b; Greenhouse, 1984; the National Research Council's Animals for Research, 1979), as many online databases such as those maintained by the Jackson Laboratories, the Mutant Mouse Regional Resource Centers, and the Zebrafish Information Network.