SLC2A4 and Insulin resistance: There is evidence to suggest an impairment in GLUT4 trafficking in human skeletal muscle which may contribute to the observed insulin resistance in these tissues10: Insulin resistance was associated with aberrant intracellular GLUT4 sorting to a denser membrane compartment than is the case in control subjects; this abnormal subcellular distribution of GLUT4 was accompanied by reduced GLUT4 translocation following in vivo insulin stimulation.18