first studied the serum levels of proinflammatory factors in a patient with severe Group 3 PH secondary to chronic obstructive pulmonary disease (COPD) and normal healthy people, and found that the serum IL-6 concentration of patients was higher than that in the control group (20 ± 14 pg/mL vs. 6 ± 0 pg/mL, p < 0.01), suggesting that IL-6 may be an important inflammatory mediator of PH (9). The gene discussed is IL6; the disease is chronic obstructive pulmonary disease.