However, it is worth noting that a striking difference exists between the 129/Sv/Ev and C57Bl/6 backgrounds; IFNγR-/- mice in the 129/Sv/Ev background undergo an apparent resolution of fibrosis at ca. 45 days post-infection [11] whereas C57Bl/6 mice fail to resolve disease. The gene discussed is IFNGR1; the disease is infection.