Biomaterial Database

Iduronate sulfatase activity in serum, lymphocytes, and fibroblasts--simplified diagnosis of the Hunter syndrome. 1976

I Liebaers, and E Neufeld

A previously described assay for iduronate sulfatase has been adapted for use with serum, lymphocytes, and fibroblasts. The assay also gives a rough measure of iduronidase activity. We have evaluated the procedure for the diagnosis of the Hunter syndrome, for the detection of Hunter heterozygotes, and for the diagnosis of certain other disorders (mucolipidoses II and III and mucopolysaccharidosis I). Hunter patients had 1-2% normal iduronate sulfatase activity in the three sources tested. The serum assay is undoubtedly the method of choice to establish the diagnosis of the Hunter syndrome. Less that 1 ml serum and 3-4 days are required to complete the procedure. Serum could not be used for the detection of iduronidase deficiency diseases, but these could easily be recognized in lymphocyte and fibroblast preparations. The iduronate sulfatase activity of sera from patients with mucolipidoses II and III was elevated 20-fold, but their parents had a normal level of the enzyme. In fibroblasts of patients with mucolipidoses II and III, both iduronate sulfatase and iduronidase activities were markedly decreased. Serum assays were not informative about the Hunter heterozygote status. However, the mean activity in lymphocytes from mothers of Hunter patients was about half of the mean normal activity. A number of obligate heterozygotes had iduronate sulfatase activity so low that they were identifiable as carriers; others, unfortunately, had a clearly normal level. The possibility of carrier detection by the lymphocyte assay needs further development.

UI	MeSH Term	Description	Entries
D007066	Iduronate Sulfatase	An enzyme that specifically cleaves the ester sulfate of iduronic acid. Its deficiency has been demonstrated in Hunter's syndrome, which is characterized by an excess of dermatan sulfate and heparan sulfate. EC 3.1.6.13.	Hunter Corrective Factor,Iduronatesulfate Sulfohydrolase,Sulfoiduronate Sulfatase,Iduronate Sulfate Sulfatase,Corrective Factor, Hunter,Factor, Hunter Corrective,Sulfatase, Iduronate,Sulfatase, Iduronate Sulfate,Sulfatase, Sulfoiduronate,Sulfate Sulfatase, Iduronate,Sulfohydrolase, Iduronatesulfate
D007068	Iduronidase	An enzyme that hydrolyzes iduronosidic linkages in desulfated dermatan. Deficiency of this enzyme produces Hurler's syndrome. EC 3.2.1.76.	alpha-L-Idosiduronase,alpha-L-Iduronidase,alpha L Idosiduronase,alpha L Iduronidase
D008059	Mucopolysaccharidosis I	Systemic lysosomal storage disease caused by a deficiency of alpha-L-iduronidase (IDURONIDASE) and characterized by progressive physical deterioration with urinary excretion of DERMATAN SULFATE and HEPARAN SULFATE. There are three recognized phenotypes representing a spectrum of clinical severity from severe to mild: Hurler syndrome, Hurler-Scheie syndrome and Scheie syndrome (formerly mucopolysaccharidosis V). Symptoms may include DWARFISM; hepatosplenomegaly; thick, coarse facial features with low nasal bridge; corneal clouding; cardiac complications; and noisy breathing.	Hurler's Syndrome,Hurler-Scheie Syndrome,Lipochondrodystrophy,Mucopolysaccharidosis V,Pfaundler-Hurler Syndrome,Scheie's Syndrome,Gargoylism,Gargoylism, Hurler Syndrome,Hurler Disease,Hurler Syndrome,Hurler's Disease,Mucopolysaccharidosis 1,Mucopolysaccharidosis 5,Mucopolysaccharidosis I-S,Mucopolysaccharidosis Type I,Mucopolysaccharidosis Type Ih,Mucopolysaccharidosis Type Ih S,Mucopolysaccharidosis Type Is,Scheie Syndrome,alpha-L-Iduronidase Deficiency,Disease, Hurler's,Gargoylisms,Hurler Scheie Syndrome,Hurler Syndrome Gargoylism,Lipochondrodystrophies,Mucopolysaccharidosis I S,Mucopolysaccharidosis Is,Mucopolysaccharidosis Type Ihs,Syndrome, Hurler's,Syndrome, Scheie's,Type Ih, Mucopolysaccharidosis,Type Ihs, Mucopolysaccharidosis,alpha L Iduronidase Deficiency,alpha-L-Iduronidase Deficiencies
D008214	Lymphocytes	White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.	Lymphoid Cells,Cell, Lymphoid,Cells, Lymphoid,Lymphocyte,Lymphoid Cell
D008297	Male		Males
D009083	Mucopolysaccharidoses	Group of lysosomal storage diseases each caused by an inherited deficiency of an enzyme involved in the degradation of glycosaminoglycans (mucopolysaccharides). The diseases are progressive and often display a wide spectrum of clinical severity within one enzyme deficiency.	Mucopolysaccharidosis
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D005260	Female		Females
D005347	Fibroblasts	Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.	Fibroblast
D006579	Heterozygote	An individual having different alleles at one or more loci regarding a specific character.	Carriers, Genetic,Genetic Carriers,Carrier, Genetic,Genetic Carrier,Heterozygotes