Human glucose transporters.

Concentrative and facilitative glucose transporters are responsible for the movement of glucose across the plasma membrane of human cells. Defects in concentrative glucose transporters cause renal glycosuria and glucose-galactose malabsorption. Alterations in facilitative glucose transporters explain the newly discovered syndrome of low CNS glucose in the presence of normal blood sugar, causing seizures and developmental delay. Defects in other facilitate glucose transporters also help explain Fanconi-Bickel syndrome, glycogen storage disease type, Id, and non-insulin-dependent diabetes mellitus.