Genetic Variants in the Hedgehog Interacting Protein Gene Are Associated with the FEV1/FVC Ratio in Southern Han Chinese Subjects with Chronic Obstructive Pulmonary Disease

BACKGROUND: Convincing evidences have demonstrated the associations between HHIP and FAM13a polymorphisms and COPD in non-Asian populations. Here genetic variants in HHIP and FAM13a were investigated in Southern Han Chinese COPD. METHODS: A case-control study was conducted, including 989 cases and 999 controls. The associations between SNPs genotypes and COPD were performed by a logistic regression model; for SNPs and COPD-related phenotypes such as lung function, COPD severity, pack-year of smoking, and smoking status, a linear regression model was employed. Effects of risk alleles, genotypes, and haplotypes of the 3 significant SNPs in the HHIP gene on FEV(1)/FVC were also assessed in a linear regression model in COPD. RESULTS: The mean FEV(1)/FVC% value was 46.8 in combined COPD population. None of the 8 selected SNPs apparently related to COPD susceptibility. However, three SNPs (rs12509311, rs13118928, and rs182859) in HHIP were associated significantly with the FEV(1)/FVC% (P(max) = 4.1 × 10(−4)) in COPD adjusting for gender, age, and smoking pack-years. Moreover, statistical significance between risk alleles and the FEV(1)/FVC% (P = 2.3 × 10(−4)), risk genotypes, and the FEV(1)/FVC% (P = 3.5 × 10(−4)) was also observed in COPD. CONCLUSIONS: Genetic variants in HHIP were related with FEV(1)/FVC in COPD. Significant relationships between risk alleles and risk genotypes and FEV(1)/FVC in COPD were also identified.