Bivariate GWAS scan identifies six novel loci associated with lipid levels and coronary artery disease

Background Plasma lipid levels are heritable and genetically associated with risk of coronary artery disease (CAD). However, genome-wide association studies (GWAS) routinely analyze these traits independently of one another. Joint GWAS for two related phenotypes can lead to a higher-powered analysis to detect variants contributing to both traits. Methods and Results We performed a bivariate GWAS to discover novel loci associated with heart disease, using a CAD Meta-Analysis (122,733 cases and 424,528 controls), and lipid traits, using data from the Global Lipid Genetics Consortium (188,577 subjects). We identified six previously unreported loci at genome-wide significance (P < 5 × 10 −8 ), three which were associated with Triglycerides and CAD, two which were associated with LDL cholesterol and CAD, and one associated with Total Cholesterol and CAD. At several of our loci, the GWAS signals jointly localize with genetic variants associated with expression level changes for one or more neighboring genes, indicating that these loci may be affecting disease risk through regulatory activity. Conclusions We discovered six novel variants individually associated with both lipids and coronary artery disease.