Analogous to FUT3 adding fucose to Type 1 chains to form LeA, alpha-(1,3)-fucosyltransferases 4, 5 and 9 (FUT4,5,9), resident on the Golgi membrane, mediate the transfer of fucose (Fuc) to Type 2 oligosaccharide chains in an α1,3 linkage to form the Lewis X antigen (LeX) (Goelz et al. 1990, Lowe et al. 1991, Weston et al. 1992, Toivonen et al. 2002). FUT10 and FUT11 also exhibit α1,3 fucosyltransferase activity (Mollicone et al. 2009).