PNPLA3 and fatty liver disease: In previous studies, genome-wide association studies identified dozens of genes with multiple polymorphisms that were associated with the increased risk of developing fatty liver disease in specific populations, including PPARG, PNPLA3, TM6SF2, PCSK9, HSD17B13, FXR, GCKR, APOB, LPIN1, UCP2, IFLN4, and PKLR (Yu et al., 2016; Lee et al., 2017; Schumacher and Guo, 2019).