SLC2A4 and gestational diabetes: Using the q-PCR approach, we demonstrated that the mRNA expression of glucose transporters (e.g., GlUT1, GLUT3, GLUT4, GLUT8) and the key genes of insulin signaling (e.g., INSR, INS1, INS2, AKT, FOXO1) were significantly decreased in GDM placentas (Fig. 1G-H).