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).
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.
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).