Spontaneous Diseases in Commonly Used Mouse Strains

Abstract

This chapter discusses the range of pathologic changes that can occur in commonly used mouse strains or stocks in the absence of intended experimental interventions. When evaluating experimental results from mice of specific strains or stocks or attempting to characterize phenotypes of mutant mice derived from them, it is important to be aware of the background pathology or phenotypes in order to determine if lesion incidences are increased or decreased compared to what occurs in non manipulated or wild-type animals of the same strain or stock. Similarly, when designing studies or developing genetically based mouse models of specific conditions, background genotypes and phenotypes may provide substantial advantage or disadvantage to achieving specific aims. Genetics or genetic constitution, including any spontaneous genetic alteration or intended manipulation, comprises the nature of the individual (or genetically identical individuals), and environmental and experiential factors, including infectious agents, comprise their nurture. The mutation confers endotoxin resistance and altered susceptibility to infections but is absent in various other C3H/He substrains. The mouse retroviruses are microbial agents of special interest because their genetic interactions blur the distinction between nature and nurture influences, reviewed in the chapter.