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).
Among smokers in the COPD cases and control subjects, two SNPs in the promoter region of TGFB1 (rs2241712 and rs1800469) and one SNP in exon 1 of TGFB1 (rs1982073) were significantly associated with COPD (P</=0.02 in all cases).
The results showed that there was no significant association between an increased risk of COPD in carriers of the T allele (TT+TC) versus the CC genotype in rs1800469 and rs1982073.