Severity of GM1 gangliosidosis and urinary oligosaccharide excretion.

Urinary oligosaccharides of GM1 gangliosidosis patients (type 2A, 4 cases; type 2B, 2 cases) were investigated using the Bio Gel system. The levels of urinary oligosaccharide excreted (nmol/mg creatinine) by the type 2A patients were 4.1 times the levels of the type 2B patients. Patients of type 2A excreted high molecular weight oligosaccharides which were not detected in the urine of type 2B, and excreted oligosaccharides with long linkages of repeating structures. Thus, type 2A apparently has biochemically different characteristics from type 2B related to urinary oligosaccharide. Differentiation of type 2A from type 2B can thus be made biochemically. The structures of 5 different kinds of oligosaccharides not reported previously were confirmed.