TM6SF2 and fatty liver disease: 3.3.7. The Proportions of Participants with Genotypes of PNPLA3 rs738409 C>G, TM6SF2 rs58542926 C>T, HSD17B13 rs9992651 G>A, and GCKR rs1260326 T>C in Subjects with Different Severities of Hepatic Steatosis