Some studies have indicated that the mean serum LDL level in COPD patients was significantly higher compared to the control group (18.62 ±7.56 vs 12.57 ± 5.90 mU/L, P < 0.05); the serum LDL level was negatively correlated with predicted FEV1% (r = −0.347, P = 0.016) but positively correlated with C-reactive protein (CRP) and reactive oxygen species (ROS) levels (33). The gene discussed is CRP; the disease is chronic obstructive pulmonary disease.