H-2 locus located on chromosome 17 in mouse and contains mouse major histocompatibility complex (MHC) genes. There is great variation and polymorphism among these genes leading to the efficient immune protection against various pathogens. Mutations in the critical H-2 locus can result in various immune compromise and dysfunction against pathogens. One mutation in the H-2 locus may increase the presentation of MHC-1 on mCMV-infected cells and results in increased recognition of the natural killer (NK) cells by the inhibitory receptors. The increased noncovalent binding of MHC-1 and inhibitory receptors due to a mutation in the H-2 locus results in inhibition of killing the mCMV-infected cells by NK cells and increase the susceptibility of infection
