Abstract P530: Pleiotropic Effects on Blood Pressure Traits Using Genome-wide Analysis of Gene-alcohol Interactions

We tested for pleiotropy in European ancestry subjects (N>90K) via GWAS of systolic and diastolic blood pressure (BP), mean arterial pressure, and pulse pressure, using gene (G)-alcohol consumption (E) interactions. The approach was a correlated meta-analysis (PMCID-PMC3773990) that combined simultaneously the 4 BP traits genome-wide GxE interactions summary meta-P values. This approach adjusts for correlations among single traits at the genomic level. A variant was considered pleiotropic when the overall correlated meta-analysis yielded P ≤5E-08 and GxE meta- P ≤E-04 for at least two single traits. The novel pleiotropic variants localize in eight loci. TTLL7 (1p31.1) is a tubulin modifier. DYRK3 (1q32.1) is a transcription regulator. MAPKAPK2 (1q32.1) is a stress-activated serine/threonine-protein kinase involved in cytokine production especially for TNF , IL6 and phosphorylates (among others) LSP1 , identified in our GWAS GxE study for individual BP traits. FSTL5 (4q32.2) is annotated as calcium ion binding . A locus at 11q13.1 includes SNX32 , EFEMP2, and FOSL1 . FOSL1 variants may regulate expression of SNX32 . EFEMP2 is implicated in blood coagulation. CATSPER2 (15q15.3) is a cation channel. CCDC151 (19p13.2) is an outer dynein arm assembly. The functions of two other loci (17q22 and 18q22.3) are unknown. We also identified 4 pleiotropic loci ( SGK223 , TNKS , GATA4 , FTO ) that were found significant at our GxE meta-GWAS of single traits in 572K multi-ancestry individuals. In addition, we detected 24 pleiotropic BP-known loci. Some of these genes relate to alcohol consumption (e.g., BLK , GATA4 , FTO ). TNKS , MAPKAPK2 and FSTL5 interact with the Wnt/β-catenin signaling pathway, which contributes to hypertension. Several pleiotropic variants showed features of regulation by locating at promoter and enhancer histone marks, at DNAse, at proteins binding sites and being eQTL. The 36 novel and BP-known loci comprising 86 significant genes were enriched for Hypertension , Cardiac arrhythmias , Myocardial infarction , Atrial fibrillation, and Left ventricular hypertrophy . Our correlated meta-analysis of GxE interaction approach identified novel pleiotropic loci and validated known BP loci, thus providing insights into the mechanisms of hypertension.