BACKGROUND: Genome-wide association studies have identified CHRNA3 as a lung cancer and chronic obstructive pulmonary disease (COPD) candidate gene in non-Hispanic Caucasian cohorts. However, there are differences in minor allele frequencies among ethnic groups, and limited data exists for Asian populations. OBJECTIVES: The aim of this case-control study was to determine whether there is an association between COPD and genetic variation in CHRNA3 in the Korean population. In addition, we investigated the association of CHRNA3 with intermediate disease phenotypes including emphysema and lung function in COPD subjects. METHODS: Two single-nucleotide polymorphisms (SNPs) in CHRNA3 (rs660652 and rs12910984) were genotyped in 219 COPD subjects registered in the Korean Obstructive Lung Disease cohort study and in 305 control subjects. Volumetric computed tomography was performed in all COPD subjects. Emphysema severity was measured quantitatively by determining the volume fraction of the lung below -950 Hounsfield units. Logistic regression analysis for case-control analysis and linear regression modeling for quantitative analysis were performed using SAS. RESULTS: This case-control analysis of 219 COPD patients and 305 control participants identified a significant association between an SNP of CHRNA3 (rs12910984) and COPD (p = 0.049). Analysis in COPD subjects revealed that genetic variations were not associated with FEV1. There was no association between SNPs and emphysema severity. However, both SNPs were significantly associated with DLCO. CONCLUSION: Genetic variations in CHRNA3 are associated with COPD in the Korean population.
BACKGROUND: Genome-wide association studies have identified CHRNA3 as a lung cancer and chronic obstructive pulmonary disease (COPD) candidate gene in non-Hispanic Caucasian cohorts. However, there are differences in minor allele frequencies among ethnic groups, and limited data exists for Asian populations. OBJECTIVES: The aim of this case-control study was to determine whether there is an association between COPD and genetic variation in CHRNA3 in the Korean population. In addition, we investigated the association of CHRNA3 with intermediate disease phenotypes including emphysema and lung function in COPD subjects. METHODS: Two single-nucleotide polymorphisms (SNPs) in CHRNA3 (rs660652 and rs12910984) were genotyped in 219 COPD subjects registered in the Korean Obstructive Lung Disease cohort study and in 305 control subjects. Volumetric computed tomography was performed in all COPD subjects. Emphysema severity was measured quantitatively by determining the volume fraction of the lung below -950 Hounsfield units. Logistic regression analysis for case-control analysis and linear regression modeling for quantitative analysis were performed using SAS. RESULTS: This case-control analysis of 219 COPD patients and 305 control participants identified a significant association between an SNP of CHRNA3 (rs12910984) and COPD (p = 0.049). Analysis in COPD subjects revealed that genetic variations were not associated with FEV1. There was no association between SNPs and emphysema severity. However, both SNPs were significantly associated with DLCO. CONCLUSION: Genetic variations in CHRNA3 are associated with COPD in the Korean population.