IREB2, CHRNA5, CHRNA3, FAM13A & hedgehog interacting protein genes polymorphisms & risk of chronic obstructive pulmonary disease in Tatar population from Russia

BACKGROUND & OBJECTIVES: Chronic obstructive pulmonary disease (COPD) is a complex chronic inflammatory disease of the respiratory system affecting primarily distal respiratory pathways and lung parenchyma. This study was aimed at investigating the association of COPD with IREB2, CHRNA5, CHRNA3, FAM13A and hedgehog interacting protein (HHIP) genes in a Tatar population from Russia. METHODS: Six single nucleotide polymorphisms (SNPs) (rs13180, rs16969968, rs1051730, rs6495309, rs7671167, rs13118928) were genotyped by the real-time polymerase chain reaction in this study (511 COPD patients and 508 controls). Logistic regression was used to detect the association of SNPs and haplotypes of linked loci in different models. Linear regression analyses were performed to estimate the relationship between SNPs and lung function parameters and pack-years. RESULTS: The rs13180 (IREB2), rs16969968 (CHRNA5) and rs1051730 (CHRNA3) were significantly associated with COPD in additive model [P(adj)=0.00001, odds ratio (OR)=0.64; P(adj)=0.0001, OR=1.41 and P(adj)=0.0001, OR=1.47]. The C-G haplotype by rs13180 and rs1051730 was a protective factor for COPD in our population (P(adj)=0.0005, OR=0.61). These results were confirmed only in smokers. The rs16969968 and rs1051730 were associated with decrease of forced expiratory volume in 1 sec % predicted (P(adj)=0.005 and P(adj)=0.0019). INTERPRETATION & CONCLUSIONS: Our study showed the association of rs13180, rs16969968 and rs1051730 with COPD and lung function in Tatar population from Russia. Further studies need to be done in other ethnic populations.