Although the genetic and molecular basis of several mutations important in resistance to Salmonella infection in mice have been identified, namely Nramp1/Slc11a1, Tlr4, and Pklr, the low frequency of naturally occurring spontaneous mutations has prompted the use of novel genomic approaches like ENU mutagenesis to identify novel host susceptibility genes to Salmonella infection [148,149,150,151,152,153]. The gene discussed is TLR4; the disease is Salmonella Infections.