Association of the miR-146aC>G, 149C>T, 196a2C>T, and 499A>G polymorphisms with colorectal cancer in the Korean population.

MicroRNAs (miRNAs) are small, 18- to 22-nucleotide non-coding RNAs that regulate target gene expression. Although recent studies focused on various diseases that harbor the miR-146aC>G (rs2910164), 149C>T (rs2292832), 196a2C>T (rs11614913), and 499A>G (rs3746444) polymorphisms, the role of miRNA genetic variants in colorectal cancer is still unknown. The present study aimed to evaluate the role of four miRNA polymorphisms in patients with colorectal cancer. We enrolled 446 colorectal cancer patients and 502 control subjects from the Korean population. We found a significantly increased colorectal cancer risk with the miR-196a2CC genotype compared with the TT/CT genotype (AOR = 1.50; 95% CI = 1.11-2.04; P = 0.01; FDR-P = 0.04). In the stratified analyses, we observed both weak and strong association data. We found stronger associations of the miR-196a2 variants in the non-diabetic and rectal cancer groups than other stratified groups. Our data suggest that the miRNA variants could affect the development of colorectal cancer in the Korean population.