Introduction and Objective: Steatotic liver disease, formerly called non-alcoholic fatty liver disease (NAFLD), is the most common cause of chronic liver disease worldwide; yet, few effective methods for prevention/treatment exist making it one of the biggest unmet public health needs of our time. To date, genetic studies have been limited to identifying common variants in predominantly European-ancestry populations or focused on surrogate phenotypes, e.g. liver enzymes, identifying association with comorbidities. Here we present a multi-ancestry whole genome sequencing (WGS) association study to discover rare variants associated with imaging-measured hepatic steatosis.
Methods: Study-, ancestry- and sex-stratified association analyses were conducted using SAIGEgds in nine studies with imaging-measured hepatic steatosis adjusted for age, sex, alcoholic drinks per week and principal component estimates of admixture. Stratified results were meta-analyzed using a fixed-effects model. Cochran’s Q-test and the I2 metric were used to estimate heterogeneity.
Results: Meta-analyses included 23,156 European, African, Hispanic and Chinese ancestry individuals and identified five significant loci (P<5x10-08): PNPLA3, PPP1R3B, HAPLN4, intergenic region on chr14 and F11-AS1. Nine additional variants trended toward association (P<5x10-07). Sex-stratified meta-analyses revealed additional associations in an intergenic region on chr10, RP11-115J16.1 and UBE3B. Variants in RP11-115J16.1 remained significant in European ancestry samples. Significantly associated variants in SLC2A1-AS1 and LINC01684 were novel loci in African Americans.
Conclusion: Taken together, multi-ancestry analysis of imaging-measured hepatic steatosis using WGS replicated previously associated loci and identified novel sex- and ancestry-specific loci. Functional studies are underway to determine the biological impact of these findings.
N. Allred: None. C. Raut: None. Y. Chen: None. A. Oliveri: None. J. O'Connell: None. K. Ryan: None. J.I. Rotter: None. S.S. Rich: None. A. Hakim: None. P. Peyser: None. L.F. Bielak: None. C. Liu: None. J.G. Terry: None. M. Fornage: None. L.E. Wagenknecht: None. E.K. Speliotes: Other Relationship; University of Michigan.
National Institute of Diabetes and Digestive Kidney Disease (R01 DK128871)