title: Clinical, Biochemical and Genetic Analysis of Biotinidase Deficiency in Iranian Population.
abstract: BACKGROUND
  Biotinidase deficiency (BTD) is an autosomal recessive disorder of biotin metabolism. Biotin is a coenzyme that enhances the action of the four enzymes that play an important role in carbohydrates, amino acid, and fatty acid metabolism. Defects in these pathways cause severe metabolic disorder in the body. In general, biotinidase deficiency can be classified into two levels: partial and profound. The incidence of BTD is 1:40,000 to 1:60,000 births in the world, even though no convincing statistical data on the prevalence of this disorder exist in Iran. In this study, we aimed to set up a test for determining biotinidase activity among the Iranian population and report BTD mutations.
  
  
  METHODS
  The quantitative method for the determination of biotinidase activity was set up in the National Biochemistry Reference Laboratory (NBRL) of Pasteur Institute of Iran in Tehran. To detect mutations in BTD, polymerase chain reaction (PCR) was performed followed by DNA sequencing.
  
  
  RESULTS
  The biotinidase activity range values were 3.81 - 8.25 nmol/min/mL. We identified 8 BTD patients out of 47 cases with neurologic signs. We detected two mutations, c.98-104del7ins3 and p.Arg79Cys, in 5 patients with profound BTD, and one p.Asp444His mutation in 3 patients with partial BTD.
  
  
  CONCLUSIONS
  Infants suffering from BTD seem healthy during their first months of life. At present, the screening program for metabolic disorders such as BTD is in progress. The patients that are BTD deficient benefit from the availability of the tests, and consequently receive the Biotin supplements before being clinically affected.
authors.affiliation: Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran, Department of Biochemistry, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Arezou
authors.initials: A
authors.lastname: Asgari
authors.affiliation: Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: Soghra
authors.initials: S
authors.lastname: Rouhi Dehnabeh
authors.affiliation: Department of Biochemistry, Mazandaran University of Medical Sciences, Sari, Iran.
authors.forename: Mehryar
authors.initials: M
authors.lastname: Zargari
authors.affiliation: Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: Soghra
authors.initials: S
authors.lastname: Khani
authors.affiliation: Department of Biochemistry, Medical School, Kermanshah University of Medical Sciences, Kermanshah, Iran.
authors.forename: Hadi
authors.initials: H
authors.lastname: Mozafari
authors.affiliation: Allergy Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Abdolreza
authors.initials: A
authors.lastname: Varasteh
authors.affiliation: Immunology Research Center, Medical School, Mashhad University of Medical Sciences, Mashhad, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Keyfi
authors.affiliation: Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: Mina
authors.initials: M
authors.lastname: Barzegari
authors.affiliation: Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: Rayhaneh
authors.initials: R
authors.lastname: Hasanzaeh
authors.affiliation: Department of Biochemistry, Pasteur Institute of Iran, Tehran, Iran.
authors.forename: Shohreh
authors.initials: S
authors.lastname: Khatami
mesh_terms: D043523:Biotinidase / Q000097:blood* / Q000235:genetics; D028921:Biotinidase Deficiency / Q000097:blood / Q000175:diagnosis* / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005820:Genetic Testing; D006801:Humans; D007492:Iran; D008297:Male; D009154:Mutation; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D043523:Biotinidase