GLUT1, GLUT3, GLUT4, and GLUT6 do not transport fructose.46,47 GLUT2 has a high Km for glucose Km (~17 mM) and a low Km for fructose (~76 mM), GLUT5 has a high affinity for fructose, and GLUT8 and GLUT9 affinities for fructose have been reported.33,34,46 Two studies have reported lower fructose-induced hepatic steatosis in GLUT8 whole-body and liver-specific GLUT8 knockout (KO) mice.48,49 In mouse livers, glut2 is the most highly expressed hepatic hexose transporter, followed by glut8 and glut9, while glut5 and glut7 have no expression (Figure S1E). This evidence concerns the gene SLC2A4 and fatty liver disease.