At the same time, the present study also analyzed the correlation between the BNP gene SNPs and serum BNP expression levels, which showed that the content of the BNP protein in the serum of the wild types at the BNP gene rs198389, rs6668352, and rs198388 loci is lower than that of heterozygotes and that of heterozygotes is lower than that of mutant homozygotes (all P<0.001), indicating that mutations in the BNP gene at the rs198389, rs6668352, and rs198388 SNPs resulted in the elevation of BNP and might be one of the causes of COPD and COPD with PH. The gene discussed is NPPB; the disease is chronic obstructive pulmonary disease.