The presence of phenotypically similar granulomas in the infected spleen and liver support the hypothesis that granulomas constitute the “spearhead” of the immune response against Brucella. Correlation between high susceptibility of MyD88−/−, IL-12−/− and IFN-γ−/− mice and strongly altered granuloma structures in these mice suggested a causal link between the presence of granulomas and Brucella growth control. The gene discussed is IFNG; the disease is Granuloma.