title: Mucopolysaccharidosis IVA within Tunisian patients: Confirmation of the two novel GALNS gene mutations.
abstract: Mucopolysaccharidosis type IVA or Morquio A disease is an autosomal recessive disease resulting from a deficiency of the lysosomal enzyme N-acetylgalactosamine-6-sulfate-sulfatase, which hydrolyses N-acetylgalactosamine-6-sulfate and galactose-6-sulfate in glycosaminoglycans. Phenotypes in Morquio A disease vary from the classical form with severe bone dysplasia, heart valve involvement, corneal opacity, short trunk dwarfism and a life span of 20 to 30 years, to attenuated forms with normal life span, mild bone involvement and mild visceral organ involvement. Unlike the other forms of mucopolysaccharidoses, Morquio A disease is characterized by normal intelligence.
  
  
  OBJECTIVE
  The aims of this study were to determine if the novel GALNS anomalies IVS1+1G-A and G66R identified in Tunisia are mutations or polymorphisms.
  
  
  METHODS
  This study was carried out on six Morquio A patients recruited from many regions of Tunisia. We have used SCCP, sequencing and enzymatic digestion.
  
  
  RESULTS
  IVS1+1G-A and G66R were two deleterious mutations and not polymorphisms.
  
  
  CONCLUSIONS
  Screening of mutations and polymorphisms in GALNS gene provide useful information on genotype/phenotype correlations. It should also facilitate more accurate genetic counselling of newly diagnosed cases and their family members.
authors.affiliation: Laboratory of Biochemistry, Farhat Hached Hospital, 4000 Sousse, Tunisia. khedhirisouhir@yahoo.fr
authors.forename: S
authors.initials: S
authors.lastname: Khedhiri
authors.forename: L
authors.initials: L
authors.lastname: Chkioua
authors.forename: H
authors.initials: H
authors.lastname: Bouzidi
authors.forename: A
authors.initials: A
authors.lastname: Dandana
authors.forename: S
authors.initials: S
authors.lastname: Ferchichi
authors.forename: H
authors.initials: H
authors.lastname: Ben Turkia
authors.forename: A
authors.initials: A
authors.lastname: Miled
authors.forename: S
authors.initials: S
authors.lastname: Laradi
mesh_terms: D000328:Adult; D001483:Base Sequence; D002811:Chondroitinsulfatases / Q000235:genetics*; D004252:DNA Mutational Analysis; D056726:Genetic Association Studies; D006801:Humans; D008969:Molecular Sequence Data; D009085:Mucopolysaccharidosis IV / Q000453:epidemiology / Q000235:genetics*; D009154:Mutation / Q000502:physiology; D011110:Polymorphism, Genetic; D018807:Polymorphism, Single-Stranded Conformational / Q000502:physiology; D022821:RNA Splice Sites / Q000235:genetics; D014416:Tunisia / Q000453:epidemiology; D054928:Validation Studies as Topic; D055815:Young Adult
chemical_list: D022821:RNA Splice Sites; D002811:Chondroitinsulfatases; C102295:GALNS protein, human