DNMT3A rs36012910 A>G polymorphism and gastric cancer susceptibility in a Chinese population

DNA-methyltransferase (DNMT)-3A plays a crucial role in embryonic development and aberrant DNA methylation in carcinogenesis. Polymorphisms of the DNMT3A gene may influence its enzymatic activity and its contribution to susceptibility to cancer. This study evaluated the association of DNMT3A rs36012910 A>G with susceptibility to gastric cancer (GC) in a Chinese population. Genomic DNA was extracted from samples taken from 340 patients with GC and 251 healthy control subjects. The genotype frequency of DNMT3A rs36012910 A>G in all subjects was detected by polymerase chain reaction–restriction fragment length polymorphism and confirmed by sequencing. Stratification analyses were used to study subgroups by age and gender and to evaluate the association of rs36012910 A>G polymorphism with genetic susceptibility to GC. All patients and control individuals were successfully genotyped for the DNMT3A rs36012910 A>G polymorphism. The frequency of DNMT3A rs36012910 allele G is 3.39 % in healthy individuals and 7.78 % in GC patients, respectively. The rs36012910 AG genotype was significantly more common in the GC group than in the controls, although the rs36012910 GG genotype was only one case in GC patients. Further stratification indicated that AG+GG genotypes were associated with susceptibility to GC in males older than 60, but this polymorphism has no significant association with GC susceptibility in females. Male individuals who carried AG+GG genotypes had a 2.362-fold increased risk of GC compared to those who carried the AA genotype. The rs36012910 allele G was associated with an increased risk of GC compared to the rs36012910 allele A. This is the first report to investigate the distribution and evaluate the association of a rare SNP in DNMT3A with genetic susceptibility to GC. DNMT3A rs36012910 A>G might become a potential biomarker for use in GC prediction, although further studies in larger groups and different populations are needed for confirmation.