Electronic Health Record-Based Genome-Wide Meta-Analysis and Mendelian Randomization Identify Metabolic and Phenotypic Consequences of Non-Alcoholic Fatty Liver Disease
Abstract Non-alcoholic fatty liver disease (NAFLD) is a complex disease linked with several chronic diseases. We aimed at identifying genetic variants associated with NAFLD as well as blood biomarkers that may be causally impacted by NAFLD. We performed a genome-wide meta-analysis of four cohorts of electronic health record-documented NAFLD (8434 cases and 770,180 controls) and confirmed known susceptibility loci (GCKR, MAU2/TM6SF2, APOE, and PNPLA3). We also identified potentially new loci (LPL, FTO and TR1B1) and report an effect of lower LPL expression in adipose tissue on NAFLD susceptibility. Mendelian randomization analyses identified an effect of NAFLD on tyrosine metabolism and on blood levels of three proteins. Positive genetic correlations between NAFLD and cardiometabolic traits and negative genetic correlations with parental lifespan, socio-economic factors and ketone bodies were observed. Altogether, this analysis revealed novel susceptibility loci for NAFLD and early biomarkers of NAFLD that could be used to identify patients with NAFLD.