Large-Scale Association Analysis Identifies 13 New Susceptibility Loci for Coronary Artery Disease

Abstract

1. The CARDIoGRAM Consortium. Large-scale association analysis identifies 13 new susceptibility loci for coronary artery disease. Nature Genetics. 2011;43:333–338. ### Study Hypothesis Recently, genome-wide association studies (GWAS) have identified several common variants that are associated with risk of coronary artery disease (CAD) and myocardial infarction (MI). The authors state that the current loci discovered in CAD and MI GWAS explain only a small fraction of the heritability of this complex disease. The authors hypothesized that a larger study would provide more power to discover common variants with modest effect sizes. Therefore, they formed the Coronary ARtery DIsease Genome-wide Replication And Meta-analysis (CARDIoGRAM) consortium, which consisted of data from 14 GWAS of CAD and MI.1 ### How Was the Hypothesis Tested? The authors performed a meta-analysis of 14 GWAS of CAD comprising 22 233 cases and 64 762 control subjects, all of European ancestry. CAD was defined angiographically in a subset (n=7364) and by history in the entire sample. Presence of MI ranged from 48.1% to 100% of each cohort. After the meta-analysis, they genotyped the lead single-nucleotide polymorphisms (SNPs) within the most promising (defined a priori as P 90% power to detect effect sizes observed in the GWAS meta-analysis. Finally, to understand potential mechanisms and intermediate pathways by which novel loci may mediate risk, the authors interrogated 3 genome-wide studies that also assessed gene expression in multiple tissues, using human cell lines, a genome-wide map of allelic expression imbalance, and other human disease traits. ### Principal Findings The analysis of approximately 135 000 individuals more than doubled the number of loci with CAD association, yielding 13 previously unidentified loci and confirming at …