%0 Journal Article
%T A functional polymorphism in the DNA methyltransferase-3A promoter modifies the susceptibility in gastric cancer but not in esophageal carcinoma
%A Hong Fan
%A Dongsheng Liu
%A Xuemei Qiu
%A Fengchang Qiao
%A Qingxiang Wu
%A Xianwei Su
%A Feng Zhang
%A Yunwei Song
%A Zhujiang Zhao
%A Wei Xie
%J BMC Medicine
%D 2010
%I BioMed Central
%R 10.1186/1741-7015-8-12
%X We selected one of the single nucleotide polymorphisms (SNPs) -448A>G in the DNMT3A promoter region and evaluated its effect on activity using a luciferase assay. -448A>G polymorphisms of DNMT3A were determined by polymerase chain reaction/restriction fragment length polymorphism and confirmed by sequencing. The distribution of -448A>G polymorphisms was detected in 208 GC patients and 346 healthy controls matched for age and gender. The distribution of -448A>G polymorphisms was also detected in 96 EC patients and matched 241 healthy controls. The association of -448A>G polymorphisms of DNMT3A and the risk of GC and EC was evaluated by stratified analysis according to the patient's age and gender.In a promoter assay, carriage of the -448 A allele showed a significantly higher promoter activity (> two fold) compared with the -448G allele (P < 0.001). The allele frequency of -448A among GC patients and controls was 32.9% versus 19.9%, respectively. Overall, we found that, compared with GG carriers, the DNMT3A -448AA homozygotes has a > six fold increased risk of GC. Stratification analysis showed that AA homozygotes have a more profound risk in the subgroups of individuals at the age range ¡Ü 60 years in GC. However, individuals with -448AG and -448AA were not statistically significantly associated with an increased risk of EC compared with those carried the -448GG genotype.The DNMT3A -448A>G polymorphism is a novel functional SNP and contributes to its genetic susceptibility to GC. -448A>G can be used as a stratification marker to predict an individual's susceptibility to GC, especially in the subgroups of individuals at the age range ¡Ü 60 years. However, the relative distribution of -448A>G in EC can not be used as a prediction marker in order to evaluate an individual's susceptibility to EC.Abnormal DNA methylation is thought to be a major early event in the development of tumours where DNA methyltransferases (DNMTs), DNMT1, DNMT3A and DNMT3B have been identified as
%U http://www.biomedcentral.com/1741-7015/8/12