Technical Abstract: Diseases have a considerable effect in the productivity of the beef cattle industry. Given the low heritability of immunity, it is necessary to identify genes involved in this response. Initial efforts to identify genomic regions associated with these characteristics in beef cattle have been limited. Technology now allows for genome-wide association studies using single nucleotide polymorphism arrays. Genome-wide association studies allow the identification of additional regions where genes involved in the response of the animal to pathogens reside. Genes of the immune system work in combination. Interactions between genes of the immune system have been identified when beef cattle are exposed to diseases. Genome-wide association studies will need to account for interactions between and within genes when identification of immunity-related genes is pursued.