BACKGROUND

A variety of organic materials (biomass) are burned for cooking and heating purposes in poorly ventilated houses; smoke from biomass combustion is considered an environmental risk factor for chronic obstructive pulmonary disease COPD. In this study, we attempted to determine the participation of single-nucleotide variants in the (hedgehog-interacting protein) gene in lung function, HHIP serum levels, and HHIP sputum supernatant levels in Mexican women with and without COPD who were exposed to biomass-burning smoke.

METHODS

In a case-control study (COPD-BS, = 186, BBES, = 557) in Mexican women, three SNPs (rs13147758, rs1828591, and rs13118928) in the gene were analyzed by qPCR; serum and supernatant sputum protein levels were determined through ELISA.

RESULTS

The rs13118928 GG genotype is associated with decreased risk ( = 0.021, OR = 0.51, CI95% = 0.27-0.97) and the recessive genetic model ( = 0.0023); the rs1828591-rs13118928 GG haplotype is also associated with decreased risk ( = 0.04, OR = 0.65, CI95% 0.43-0.98). By the dominant model (rs13118928), the subjects with one or two copies of the minor allele (G) exhibited higher protein levels. Additionally, two correlations with the AG genotype were identified: BBES with FEV ( = 0.03, r = 0.53) and COPD-BS with FEV/FVC ( = 0.012, r = 0.54).

CONCLUSIONS

Single-nucleotide variants in the gene are associated with decreased COPD risk, higher HHIP serum levels, and better lung function in Mexican women exposed to biomass burning.