APOB and fatty liver disease: Several genes we identified are involved in lipid metabolism, including APOB, APOC3, LDLR, and PPARG. First, APOB LOF variants cause familial hypobetalipoproteinemia, wherein defective hepatic lipoprotein secretion results in hepatic steatosis that frequently progresses to fibrosis and hepatocellular carcinoma [17, 23, 45, 46].