We found that CFH was significantly higher in serum or synovial fluid of RA patients compared with those of healthy controls (606.6±185.8 μg/ml vs 472.4±96.7 μg/ml, p=0.0003) or osteoarthritis patients (126.8±29.2 μg/ml vs 46.5±16.3 μg/ml, p=0.0005). The gene discussed is CFH; the disease is osteoarthritis.