The pathological process by which IPF develops is very complex and involves the activation of alveolar epithelial cells as well as the proliferation of fibroblasts and differentiation into myofibroblasts; likewise, various growth factors such as TGF-β intervene, leading to irreversible damage to the alveolar architecture. The gene discussed is TGFB1; the disease is idiopathic pulmonary fibrosis.