title: DNMT3a rs1550117 polymorphism association with increased risk of Helicobacter pylori infection.
abstract: BACKGROUND
  DNA methyltransferase-3a (DNMT3a) plays significant roles in embryogenesis and the generation of aberrant methylation in carcinogenesis. This study aimed to investigate associations between single nucleotide polymorphisms (SNPs) of the DNMT3a gene and risk of Helicobacter pylori infection, gastric atrophy and gastric cancer.
  
  
  METHODS
  The subjects comprised 447 patients with gastric cancer; 111 individuals with gastric atrophy and 961 healthy controls. Two SNPs (rs1550117 and rs13420827) of the DNMT3a gene were genotyped by Taqman assay. DNMT3a expression was analyzed in cancer tissues from 89 patients by tissue microarray technique. Odds ratio (ORs) and 95% confidence intervals were calculated by multivariate logistic regression.
  
  
  RESULTS
  Among healthy controls, risk of H.pylori infection was significantly higher in subjects with the rs1550117 AA genotype, compared to those with GG/AG genotypes of DNMT3a [OR=2.08, (95%CI: 1.02-4.32)]. However, no significant correlation was found between the two SNPs and risk of developing gastric atrophy or gastric cancer. In addition, no increase in DNMT3a expression was observed in the gastric cancer with H.pylori infection.
  
  
  CONCLUSIONS
  This study revealed that DNMT3a rs1550117 polymorphism is significantly associated with an increased risk of H. pylori infection, but did not support any evidence for contributions of DNMT3a rs1550117 and rs13420827 to either gastric atrophy or gastric cancer. The biological roles of DNMT3a polymorphisms require further investigation.
authors.affiliation: Department of Gastric and Colorectal Surgery, First Hospital of Jilin University, Changchun, China E-mail : jiangjing19702000@jlu.edu.cn.
authors.forename: Xue-Yuan
authors.initials: XY
authors.lastname: Cao
authors.forename: Zhi-Fang
authors.initials: ZF
authors.lastname: Jia
authors.forename: Dong-Hui
authors.initials: DH
authors.lastname: Cao
authors.forename: Fei
authors.initials: F
authors.lastname: Kong
authors.forename: Mei-Shan
authors.initials: MS
authors.lastname: Jin
authors.forename: Jian
authors.initials: J
authors.lastname: Suo
authors.forename: Jing
authors.initials: J
authors.lastname: Jiang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics*; D000090205:DNA Methyltransferase 3A; D005260:Female; D005757:Gastritis, Atrophic / Q000235:genetics; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D016481:Helicobacter Infections / Q000235:genetics*; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012306:Risk; D013274:Stomach Neoplasms / Q000235:genetics*
chemical_list: C000717967:DNMT3A protein, human; D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A