Fucosidosis in a native-born Briton.

This investigation reports the biochemical findings in a native-born Briton suffering from the adult form of fucosidosis. Alpha-L-fucosidase, alpha-L-iduronidase, and beta-D-galactosidase were studied in cultured fibroblast and leucocytes from the patient with fucosidosis, her maternal grandfather, and several normal controls. A complete lack of alpha-L-fucosidase activity was found in the patient's fibroblasts and leucocytes while the grandfather exhibited a heterozygous level of alpha-L-fucosidase activity in his leucocytes. Excessive excretion of what is very likely to be a fucose-containing sphingolipid was demonstrated in the patient's urine by thin-layer chromatography. Compared with five isoenzyme forms of alpha-L-fucosidase activity in normal leucocytes, cellulose acetate electrophoresis of the patient's leucocytes produced evidence of a single band of slight activity associated with one of the isoenzymes. This residual activity probably accounts for the survival of such patients into adolescence and beyond.