Catalyzes the transfer of L-fucose, from a guanosine diphosphate-beta-L-fucose, to the terminal galactose on both O- and N-linked glycans chains of cell surface glycoproteins and glycolipids and the resulting epitope regulates several processes such as cell-cell interaction including host-microbe interaction, cell surface expression and cell proliferation (PubMed:7876235, PubMed:8018146, PubMed:12692541). Preferentially fucosylates gangliosides GA1 and GM1 in the antrum, cecum and colon and in the female reproductive organs (By similarity). Fucosylated host glycoproteins or glycolipids mediate interaction with intestinal microbiota influencing its composition (PubMed:22068912, PubMed:21625510, PubMed:24733310). Creates a soluble precursor oligosaccharide FuC-alpha ((1,2)Galbeta-) called the H antigen which is an essential substrate for the final step in the soluble ABO blood group antigen synthesis pathway (PubMed:7876235). a beta-D-galactosyl-(1->3)-N-acetyl-beta-D-glucosaminyl derivative + GDP-beta-L-fucose = an alpha-L-Fuc-(1->2)-beta-D-Gal-(1->3)-beta-D-GlcNAc derivative + GDP + H(+) a beta-D-galactosyl-(1->4)-N-acetyl-beta-D-glucosaminyl derivative + GDP-beta-L-fucose = an alpha-L-Fuc-(1->2)-beta-D-Gal-(1->4)-beta-D-GlcNAc derivative + GDP + H(+) a neolactoside nLc4Cer + GDP-beta-L-fucose = a neolactoside IV(2)-alpha-Fuc-nLc4Cer + GDP + H(+) a neolactoside nLc4Cer(d18:1(4E)) + GDP-beta-L-fucose = a neolactoside IV(2)-alpha-Fuc-nLc4Cer(d18:1(4E)) + GDP + H(+) ganglioside GM1 + GDP-beta-L-fucose = ganglioside Fuc-GM1 + GDP + H(+) ganglioside GA1 + GDP-beta-L-fucose = ganglioside Fuc-GA1 + GDP + H(+) GDP-beta-L-fucose + Lc4Cer = alpha-L-fucosyl-(1->2)-beta-D-galactosyl-(1->3)-N-acetyl-beta-D-glucosaminyl-(1->3)-beta-D-galactosyl-(1->4)-beta-D-glucosyl-(1<->1')-ceramide + GDP + H(+) a beta-D-Gal-(1->3)-beta-D-GlcNAc-(1->3)-beta-D-Gal-(1->4)-beta-D-Glc-(1<->1')-Cer(d18:1(4E)) + GDP-beta-L-fucose = alpha-L-fucosyl-(1->2)- beta-D-galactosyl-(1->3)-N-acetyl-beta-D-glucosaminyl-(1->3)-beta-D-galactosyl-(1->4)-beta-D-glucosyl-(1<->1')-N-acylsphing-4-enine + GDP + H(+) ganglioside GD1b + GDP-beta-L-fucose = ganglioside Fuc-GD1b + GDP + H(+) ganglioside GM1 (d18:1(4E)) + GDP-beta-L-fucose = gangliosideFuc-GM1 (d18:1(4E)) + GDP + H(+) GDP-beta-L-fucose + globoside GalGb4Cer (d18:1(4E)) = GDP + globoside Globo-H (d18:1(4E)) + H(+) a lactoside III(4)-a-Fuc-Lc4Cer + GDP-beta-L-fucose = a lactoside IV(2),III(4)-a-[Fuc]2-Lc4Cer + GDP + H(+) beta-D-galactosyl-(1->3)-N-acetyl-D-galactosamine + GDP-beta-L-fucose = alpha-L-fucosyl-(1->2)-beta-D-galactosyl-(1->3)-N-acetyl-D-galactosamine + GDP + H(+) Protein modification; protein glycosylation. Membrane-bound form in trans cisternae of Golgi. Small intestine, colon and lung. Three alleles have been identified in the Japanese population: Se1, Se2, and Sej. Common polymorphisms in FUT2 define the vitamin B12 plasma level quantitative trait locus 1 (B12QTL1) [MIM:612542]. Vitamin B12 found in meat and milk products is necessary for the formation of red blood cells, DNA synthesis during cell division, and maintenance of the myelin nerve sheath, among other functions. Deficiency in vitamin B12, clinically associated with pernicious anemia, cardiovascular disease, cancer, and neurodegenerative disorders, is often related to poor intestinal B12 absorption rather than direct dietary deficiency. Genetic variation in FUT2 results in the non-secretor phenotype which gives rise to non-functional FUT2, resulting in a lack of the H type-1 oligosaccharide ligand in secretions, and this prevents Norwalk virus binding contributing to resistance to Norwalk virus infection. There are two genes (FUT1 and FUT2) which encode galactoside 2-L-fucosyltransferase. They are expressed in a tissue-specific manner with expression restricted to cells of mesodermal or endodermal origin respectively. Belongs to the glycosyltransferase 11 family. Blood group antigen gene mutation database Fucosyltransferase 2