Fucosidase Alpha L2, Plasma (FUCa2)

The FUCA2 locus regulates the level of alpha-fucosidase in plasma (Ng et al., 1976) and fibroblasts (Van Elsen et al., 1983) but not in leukocytes. Wood (1979) suggested that the frequency of low plasma fucosidase (62%) makes it a useful marker in linkage studies. Wood (1977) argued that plasma and leukocyte alpha-L-fucosidases are under the same genetic control and that the electrophoretic polymorphism of the enzyme in leukocytes and the enzyme in fucosidosis is determined by mutations at the same locus. In fucosidosis, deficiency of alpha-L-fucosidase is found in both plasma and leukocytes. Normal individuals with low plasma enzyme but normal leukocyte enzyme were described by Ng et al. (1976); however, plasma enzyme is different electrophoretically from leukocyte enzyme.