The Association between Nod2 R702w Polymorphism and Susceptibility to Colorectal Cancer in Romanian Patients

It is well recognized that the inflammatory bowel disease (IBD) is associated with an increased risk of colorectal cancer (CRC). More susceptibility IBD genes have been reported, NOD2 being one of the most extensively investigated. The aim of this study was to evaluate a possible correlation between NOD2 rs2066844 C>T (also known as Arg702Trp or R702W) variant and CRC risk in a Romanian population. A total of 373 Romanian subjects (108 patients diagnosed with sporadic CRC and 265 controls) were enrolled in this hospital-based case-control study. The NOD2 R702W variants were detected by Real-time PCR using a predesigned TaqMan Genotyping Assay. The association between the genetic risk variant and CRC was expressed as odds ratios (OR) with 95% confidence intervals (CI). We did not find any statistically significant difference when we compared CC genotype with CT genotype (OR 1.1, 95% CI: 0.46-2.61; p=0.83) between CRC patients and controls. No TT homozygous genotype was detected. Also, we compared allele frequencies and no correlation was found (OR 1.09, 95% CI: 0.47-2.56; p=0.84). No association was found in the stratified analysis by tumor site, Dukes' stage and histological subtype. Our study suggests that the NOD2 R702W variant is not associated with CRC risk in the Romanian population. Further data from different and larger populations is required to determine whether NOD R702W SNP has effects on susceptibility to CRC.