Sodium/glucose cotransporter 1 (SGLT1) actively transports glucose into cells by Na+ co-transport with a Na+ to glucose coupling ratio of 2:1. Efficient substrate transport in mammalian kidneys is provided by the concerted action of a low affinity, high capacity, and a high affinity low capacity Na+/glucose co-transporter arranged in series along kidney pro, Xenopus/Amphibian,imal tubules Defects in SGLT1 are the cause of congenital glucose/galactose malabsorption (GGM). GGM is an intestinal monosaccharide transporter deficiency. GGM is an autosomal recessive disorder manifesting itself within the first weeks of life. It is characterized by severe diarrhea and dehydration which are usually fatal unless glucose and galactose are eliminated from the diet.