Association analysis
In performing the association tests, SNPs were analyzed with PLINK (http://pngu.mgh.harvard.edu/~purcell/plink/) and SAS version 9.1 (SAS institute Inc., Cary, NC, USA). Individuals who were on lipid-lowering therapy and hypertensive medications were excluded for dyslipidemia-related phenotypes, such as TG, HDL-C, and LDL-C. LDL-C concentrations were calculated with Friedewald's formula [18]. Missing values were assigned for individuals with TG over 400 mg/dL. The dyslipidemia-related phenotypes were tested by multivariate linear regression analysis in an additive genetic model (1-d.f.), including age, sex, and recruitment area as covariates. TG and HDL-C were transformed prior to analysis using natural log transformation to remove skewing. LDL-C was normally distributed, and no transformations were required. A GRS was examined using multivariate linear regression analysis, adjusting for age, sex, and recruitment area.