Objective: Colorectal cancer (CRC) is one of the most common gastrointestinal tumors depending on genetic and environmental factors. In addition, smoking, unhealthy diet habit and environmental carcinogenic agents are also the assumed risk factors of CRC, such as alcohol, low methionine, low folate diets. DNA methylation, a major epigenetic modification involving the addition of a methyl group to the 5′ position of a cytosine in a CpG dinucleotide, maintains chromosomal stability and regulates gene expression and has been reported to play a significant role in the development and progression of various cancers. DNA methylation is typically mediated by DNA methyltransferases (DNMTs), specifically DNMT1, DNMT3A and DNMT3B. In this study we aimed to investigate whether DNMT3B gene polymorphisms have any effect on the pathogenesis of colorectal cancer.

Materials and Methods: The study group consisted of 98 colorectal cancer patients and 96 healthy controls. Three SNPs of DNMT3B gene, rs2424913, rs1569686 and rs2424908 were genotyped by PCR-RFLP technique.

Results: When genotype and allele frequencies of three SNPs compared between patients and controls, p values ranged from 0. 08 to 0.98.

Conclusions: The results of study show that rs2424913, rs1569686 and rs2424908 polymorphisms of DNMT3B gene have not a primer effect on pathogenesis of colorectal cancer.