title: Genetic analysis of the UPB1 gene in two new Chinese families with β-ureidopropionase deficiency and the carrier frequency of the mutation c.977G>A in Northern China.
abstract: OBJECTIVE
  The purpose of the study was to investigate mutations of the UPB1 gene in two Chinese families with β-ureidopropionase deficiency and the heterozygous carrier frequency in Chinese.
  
  
  METHODS
  Genomic DNA was extracted from peripheral blood leukocytes from all available family members and 500 unrelated healthy controls. Then, all exons and flanking intron regions of the UPB1 gene were amplified by PCR and analyzed by direct sequencing in two patient-families. Finally, the carrier frequency of the c.977G>A (p.R326Q) mutation was identified by PCR restriction fragment length polymorphism in 500 healthy controls.
  
  
  RESULTS
  The two patients had the same homozygous missense mutation in exon 9 (c.977G>A; p.R326Q), and the carrier frequency of this mutation was 2.8 % in the Northern Chinese population, which suggests that about 1:5,102 Chinese are expected to suffer from UPB1 deficiency.
  
  
  CONCLUSIONS
  The c.977G>A (p.R326Q) is the most common mutation of the UPB1 gene in Chinese. The predicted incidence indicates that β-ureidopropionase deficiency is significantly underdiagnosed in the Chinese population. It should be necessary to add β-ureidopropionase deficiency to high-risk screening for the symptomatic patients group.
authors.affiliation: Tianjin Pediatric Research Institute, Tianjin Children's Hospital, Tianjin, China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Shu
authors.forename: Xiqian
authors.initials: X
authors.lastname: Lv
authors.forename: Shuzhen
authors.initials: S
authors.lastname: Jiang
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Zhang
authors.forename: Chunhua
authors.initials: C
authors.lastname: Zhang
authors.forename: Yingtao
authors.initials: Y
authors.lastname: Meng
authors.forename: Aiming
authors.initials: A
authors.lastname: Situ
authors.forename: Haiquan
authors.initials: H
authors.lastname: Xu
authors.forename: Li
authors.initials: L
authors.lastname: Song
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics*; D000581:Amidohydrolases / Q000172:deficiency* / Q000235:genetics; D044466:Asian People / Q000235:genetics*; D001927:Brain Diseases / Q000235:genetics*; D002675:Child, Preschool; D002681:China; D004252:DNA Mutational Analysis; D005091:Exons / Q000235:genetics; D005260:Female; D005787:Gene Frequency / Q000235:genetics*; D006580:Genetic Carrier Screening; D005820:Genetic Testing; D006720:Homozygote; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D009069:Movement Disorders / Q000235:genetics*; D020125:Mutation, Missense / Q000235:genetics; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length / Q000235:genetics; D011686:Purine-Pyrimidine Metabolism, Inborn Errors / Q000235:genetics*
chemical_list: D000581:Amidohydrolases; C021590:beta-ureidopropionase