title: Single nucleotide polymorphisms and haplotypes of histamine N-methyltransferase in patients with gastric ulcer.
abstract: BACKGROUND
  Histamine plays a crucial role in the regulation of gastric acid secretion, which is involved in the pathogenesis of peptic ulcer. Histamine N-methyltransferase (HNMT) is the major metabolizing enzyme for histamine inactivation in human stomach.
  
  
  OBJECTIVE
  This study aims to determine whether there exists a relationship between HNMT gene polymorphisms and the risk for gastric ulcer (GU).
  
  
  METHODS
  118 GU patients and 154 ethnically matched control subjects were enrolled and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays were developed to genotype all these subjects for the T-1637C, C-411T, C314T and A1097T point mutations in HNMT gene. Haplotypes were reconstructed from the genotype data.
  
  
  RESULTS
  Frequencies of the variant alleles in cases and controls were 0.398 vs 0.396 for T-1637C, 0.144 vs 0.110 for C-411T, 0.034 vs 0.042 for C314T, and 0.242 vs 0.273 for A1097T, respectively, with no significant difference for any locus between the two groups (all P > 0.05). Also the frequencies of genotypes, haplotypes and haplotype pairs based on these polymorphisms did not differ significantly between cases and controls.
  
  
  CONCLUSIONS
  This study provided no evidence for the involvement of HNMT polymorphisms in the susceptibility to GU.
authors.affiliation: Pharmacogenetics Research Institute, Institute of Clinical Pharmacology, Central South University, 410078 Changsha, Hunan, P.R. China.
authors.forename: G-L
authors.initials: GL
authors.lastname: Chen
authors.forename: B
authors.initials: B
authors.lastname: Zhu
authors.forename: W-P
authors.initials: WP
authors.lastname: Nie
authors.forename: Z-H
authors.initials: ZH
authors.lastname: Xu
authors.forename: Z-R
authors.initials: ZR
authors.lastname: Tan
authors.forename: G
authors.initials: G
authors.lastname: Zhou
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.forename: W
authors.initials: W
authors.lastname: Wang
authors.forename: H-H
authors.initials: HH
authors.lastname: Zhou
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006239:Haplotypes; D006637:Histamine N-Methyltransferase / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D013276:Stomach Ulcer / Q000235:genetics* / Q000503:physiopathology
chemical_list: D006637:Histamine N-Methyltransferase