title: alpha-N-acetylgalactosaminidase deficiency, a new lysosomal storage disorder.
abstract: A new lysosomal storage disease with autosomal recessive inheritance is described in two male siblings of 5 1/2 and 4 years of age. Clinical manifestations started after 9 months of age with neurological symptoms, followed by progressive psychomotor deterioration. Urinary oligosaccharide excretion was abnormal and showed a characteristic pattern on chromatography. Enzyme assays showed a profound deficiency of lysosomal alpha-N-acetylgalactosaminidase in cultured fibroblasts, leukocytes and plasma from the patients and reduced activity in material from the parents. The deficiency was demonstrated both with an artificial substrate and a natural one, the blood group A trisaccharide. Excessive intra-lysosomal storage of alpha-N-acetylgalactosamine-containing material was demonstrated in cultured fibroblasts from the patients, using the lectin from Helix pomatia which is specific for terminal alpha-N-acetylgalactosamine residues.
authors.affiliation: Department of Clinical Genetics, Erasmus University, Rotterdam, The Netherlands.
authors.forename: O P
authors.initials: OP
authors.lastname: van Diggelen
authors.forename: D
authors.initials: D
authors.lastname: Schindler
authors.forename: R
authors.initials: R
authors.lastname: Willemsen
authors.forename: M
authors.initials: M
authors.lastname: Boer
authors.forename: W J
authors.initials: WJ
authors.lastname: Kleijer
authors.forename: J G
authors.initials: JG
authors.lastname: Huijmans
authors.forename: W
authors.initials: W
authors.lastname: Blom
authors.forename: H
authors.initials: H
authors.lastname: Galjaard
mesh_terms: D000116:Acetylgalactosamine / Q000378:metabolism; D002478:Cells, Cultured; D002675:Child, Preschool; D002855:Chromatography, Thin Layer; D005347:Fibroblasts / Q000201:enzymology; D006596:Hexosaminidases / Q000172:deficiency*; D006651:Histocytochemistry; D006801:Humans; D037102:Lectins; D007962:Leukocytes / Q000201:enzymology; D008247:Lysosomes / Q000201:enzymology*; D008297:Male; D009844:Oligosaccharides / Q000652:urine; D048809:alpha-N-Acetylgalactosaminidase
chemical_list: C038095:Helix lectin; D037102:Lectins; D009844:Oligosaccharides; D006596:Hexosaminidases; C482722:NAGA protein, human; D048809:alpha-N-Acetylgalactosaminidase; D000116:Acetylgalactosamine