Alpha-1,2-fucosyltransferase. Alpha-1,2-fucosyltransferases (Fut1, Fut2) catalyze the transfer of alpha-L-fucose to the terminal beta-D-galactose residue of glycoconjugates via an alpha-1,2-linkage, generating carbohydrate structures that exhibit H-antigenicity for blood-group carbohydrates. These structures also act as ligands for morphogenesis, the adhesion of microbes, and metastasizing cancer cells. Fut1 is responsible for producing the H antigen on red blood cells. Fut2 is expressed in epithelia of secretory tissues, and individuals termed "secretors" have at least one functional copy of the gene; they secrete H antigen which is further processed into A and/or B antigens depending on the ABO genotype. O-fucosyltransferase-like proteins are GDP-fucose dependent enzymes with similarities to the family 1 glycosyltransferases (GT1). They are soluble ER proteins that may be proteolytically cleaved from a membrane-associated preprotein, and are involved in the O-fucosylation of protein substrates, the core fucosylation of growth factor receptors, and other processes.