Genome-wide association studies identify locus on 6p21 influencing lung function in the Korean population

Background and objective Loss of lung function is an important chronic obstructive pulmonary disease phenotype and decreased forced expiratory volume in 1 s (FEV₁) is an independent risk factor of morbidity and mortality. Genome-wide association studies (GWAS) identifying genetic variants underlying lung function have been performed mostly in Caucasian populations. In this study, we aimed to identify genetic variants influencing lung function in a Korean population. Methods GWAS on lung function (FEV₁ and FEV ₁/forced vital capacity (FVC) ratio) were performed in two cohort studies. A population-based cohort, the Korean Association Resource phase 3 (KARE3) (6223 subjects), served as a discovery set. The replication analysis was performed in a family-based cohort, the Healthy Twin Study (HTS; 2730 subjects). Dense single-nucleotide polymorphism array data from each study were imputed and used for genetic analysis. Results At the discovery phase, variants in 6p21 and 17q24 showed the strongest association with FEV₁/FVC ratio and FEV₁. Several variants in FAM13A on 4q22 locus exhibited positive association with FEV₁/FVC ratio. In the replication set, PPT2 in the 6p21 region showed significant association with lung function in the HTS, although the 4q22 locus and the 17q24 locus were not replicated. Conclusions We identified that PPT2 on chromosome 6p21 is associated with loss of lung function in the Korean population. The aim of this study was to identify genetic determinants of lung function in a Korea population. Locus on chromosome 6p21 was identified to regulate lung function in two cohort studies. Additionally, chromosome 17q24 near SOX9 showed a strong association in one study, although it was not replicated.