This low dose of bleomycin is not sufficient to induce pulmonary fibrosis in wild-type mice, but synergizes with short telomeres in the context of Tert-/- mice leading to full-blown, progressive pulmonary fibrosis, recapitulating many of the features of the human disease, including the presence of short telomeres (Blasco et al., 1997). The gene discussed is TERT; the disease is pulmonary fibrosis.