Ext1 is a symbol for the gene, Exostosin glycosyltransferase 1, in humans. Other names include: Exostosin-1; Multiple exostoses protein 1; Putative tumor suppressor protein EXT1; Exostosin-1 ; EXT; TRPS2; TTV. The encoded protein is an enzyme with an amino acid length of 746 and a mass of 86.3 kDa. Other isoforms may exist. Ext1 is a member of the Glycosyltransferase 47 family. This gene shares homology with other species, including: Mouse, Fly, Rat, Arabidopsis, Frog, Chicken.