The genetics of immune and infection phenotypes in wild mice, Mus musculus domesticus.

Wild animals are under constant threat from a wide range of micro- and macroparasites in their environment. Animals make immune responses against parasites, and these are important in affecting the dynamics of parasite populations. Individual animals vary in their anti-parasite immune responses. Genetic polymorphism of immune-related loci contributes to inter-individual differences in immune responses, but most of what we know in this regard comes from studies of humans or laboratory animals; there are very few such studies of wild animals naturally infected with parasites. Here we have investigated the effect of polymorphism in immune-related loci (the MHC, and genes coding for cytokines and Toll-like receptors) on a wide range of immune and infection phenotypes in UK wild house mice, Mus musculus domesticus. We found strong effects of polymorphisms in various MHC and cytokine coding loci on both immune measures (antibody concentration and cytokine production) and on infection phenotypes (infection with mites, worms and viruses). Our study provides a comprehensive view of how polymorphism of immune-related loci affects immune and infection phenotypes in naturally infected wild rodent populations.