Onset of arthritis before pulmonary manifestation; double joint swelling; thickened alveolar walls, deposition of collagen fibers, pleural thickening in the lung with increased levels of TNF‐α, IL‐6, and IL‐1β, inflammatory cell infiltration: lymphocytes, eosinophilic granulocytes, and macrophages. The gene discussed is TNF; the disease is arthritic joint disease.