Ifngr1−/− mice challenged i.v. with 106 CFU of BCG were unable to control the infection: the bacterial load in the spleen increased to 7.4 ± 0.3 (Log10 CFU) by 45 d after infection and exceeded 8 Log10 CFU in dying animals (Figure 1B). The gene discussed is IFNGR1; the disease is infection.