No associations with COPD were identified for other polymorphisms evaluated in the present study including rs1800469 (T allele compared with C allele, OR =0.89, 95% CI: 0.77-1.02, <i>P</i>=0.099), rs2241712 (A allele compared with G allele, OR =1.03, 95% CI: 0.89-1.20, <i>P</i>=0.666), rs6957 (A allele compared with G allele, OR =1.14, 95% CI: 0.95-1.36, <i>P</i>=0.160), and rs2241718 (C allele compared with T allele, OR =0.95, 95% CI: 0.79-1.14, <i>P</i>=0.571).
Haplotype analysis showed that the frequencies of the GC, GT haplotypes of rs2241718 (TGF-β1 gene), and rs6957 (CDC97 gene) were significantly higher in the control group than in the COPD case group (p=1.88×10-9); the frequencies of the TT haplotype of rs1205 and rs2808630 (CRP gene) were significantly higher in the control group (p=0.0377).