Similar to the previous study with M. tuberculosis strain H37Rv (39), dKO mice succumbed to BTB 02-171 infection significantly earlier than did Ifngr−/− mice (median survival, 32 versus 35 d, respectively, p < 0.0025; Fig. 3A), whereas none of the WT or Ifnar−/− mice succumbed to disease, even at late stages of infection (surviving >200 d; data not shown). The gene discussed is IFNGR1; the disease is infection.