However, whereas Fas-sufficient mice underwent homeostatic fibrosis resolution by 6–9 weeks (9, 10, 24, 50), fibroblast Fas deficiency in both Dermo1-Cre;Fas–/– and Col1-CreERT2;Fas–/– mice inhibited homeostatic fibrosis resolution and led to persistent pulmonary fibrosis for at least 9 weeks. The gene discussed is FAS; the disease is pulmonary fibrosis.