Juvenile Sandhoff disease: some properties of the residual hexosaminidase in cultured fibroblasts.

The residual hexosaminidase isoenzymes in juvenile Sandhoff and infantile Sandhoff disease fibroblasts, have been determined by starch gel electrophoresis and column isoelectric focusing. Hex A and hex S are the major residual isozymes in fibroblasts from the juvenile patient, while hex B is barely detectable. Only hex S could be detected in fibroblasts from infantile Sandhoff patients. These results suggest that the defects in juvenile and infantile Sandhoff disease may be different allelic modifications of the beta subunit common to hex A and hex B.