Multiple deficiency of mucopolysaccharide sulfatases in mucosulfatidosis

Abstract

Fibroblasts of four patients affected with mucosulfatidosis (multiple sulfatase deficiency, Austin variant of metachromatic leukodystrophy) were assayed for activities of the five sulfatases known to degrade mucopolysaccharides. These were iduronide 2-sulfate sulfatase, sulfamidase, N-acetyl-galactosamine 6-sulfate sulfatase, arylsulfatase B (N-acetylgalactosamine 4-sulfate sulfatase), and N-acetylglucosamine 6-sulfate sulfatase. The activities of these five sulfatases were severely depressed, thus confirming the known deficiency of arylsulfatase B and the absence of the Hunter and Sanfilippo III A corrective factors that have iduronide 2-sulfate sulfatase and sulfamidase activity, respectively. Together with earlier reports on the deficiencies of arylsulfa- tases A and C, cholesteryl sulfatase, and dehydroepiandrosterone sulfatae, mucosulfatidosis is now characterized by the deficiency of nine different sulfatases. Speculation: Mucosulfatidosis is a disease characterized by the deficiency of multiple sulfatases in cultured fibroblasts in contrast to the deficiencies of singe sulfatases that are known for the five mucopolysaccharide degrading sulfatases and arylsulfatase A. The genes responsible for the expression of the sulfatases are located both on autosomes and the X-chromosomes. Mucosulfatidosis fibroblasts should provide an experimental model for the study of a hitherto unknown common mechanism responsible for the expression of sulfatase activities. © 1979 International Pediatric Research Foundation, Inc.