title: OTC gene in ornithine transcarbamylase deficiency: clinical course and mutational spectrum in seven Korean patients.
abstract: BACKGROUND
  Ornithine transcarbamylase deficiency, an inborn error of metabolism, is the most common urea cycle disorder and is caused by mutations in the OTC gene located on Xp21. In this study, the clinical and genetic characteristics of seven Korean patients with ornithine transcarbamylase deficiency were analyzed.
  
  
  METHODS
  During 2009-2012, a total of seven patients (three male and four female patients) from six unrelated families were diagnosed with ornithine transcarbamylase deficiency by biochemical or molecular analysis. OTC gene sequencing analysis was performed in six of these patients. Clinical manifestations, clinical courses, and the results of genetic studies were reviewed retrospectively.
  
  
  RESULTS
  The median follow-up period for the seven patients with ornithine transcarbamylase deficiency was 44 months (11.9-150 months). Clinical manifestations of ornithine transcarbamylase deficiency included vomiting and seizure, which were the most frequent signs at admission. Two of the four heterozygous female patients (50%) experienced severe neurological sequelae. The early onset male patient characterized severe neurological deficits. The late-onset male patient recovered completely from acute encephalopathy and coma without any neurological deficits. Direct sequencing and multiplex ligation-dependent probe amplification analysis of OTC gene revealed five different mutations. Of these mutations, two were novel (c.867-3T>C and c.664_667delinsAC).
  
  
  CONCLUSIONS
  Ornithine transcarbamylase deficiency was genetically heterogeneous in the seven Korean patients with confirmed ornithine transcarbamylase deficiency diagnosis by biochemical findings and/or genetic analysis, together with two novel mutations in the OTC gene. We hope that these data will contribute to a better understanding of the clinical course and distinct molecular genetic characteristics of Korean patients with ornithine transcarbamylase deficiency.
authors.affiliation: Department of Pediatrics, Kosin University Gospel Hospital, Busan, South Korea.
authors.forename: Jung Hyun
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Medical Genetics Clinic and Laboratory, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea.
authors.forename: Gu-Hwan
authors.initials: GH
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Medical Genetics Clinic and Laboratory, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, South Korea.
authors.forename: Han-Wook
authors.initials: HW
authors.lastname: Yoo
authors.affiliation: Department of Pediatrics, Pediatric Genetics and Metabolism, Pusan National University Children's Hospital, Pusan National University School of Medicine, Yangsan, South Korea; Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital, Yangsan, South Korea. Electronic address: chongkun@pusan.ac.kr.
authors.forename: Chong-Kun
authors.initials: CK
authors.lastname: Cheon
mesh_terms: D000293:Adolescent; D044466:Asian People / Q000235:genetics; D004252:DNA Mutational Analysis; D005190:Family; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007723:Korea; D008297:Male; D009154:Mutation; D009954:Ornithine Carbamoyltransferase / Q000235:genetics*; D020163:Ornithine Carbamoyltransferase Deficiency Disease / Q000175:diagnosis / Q000235:genetics* / Q000503:physiopathology; D055815:Young Adult
chemical_list: D009954:Ornithine Carbamoyltransferase
keywords: OTC gene; direct sequencing; multiple ligation-dependent probe amplification; ornithine transcarbamylase deficiency