Association between the 308 G>A variant of the TNF-α gene and risk of colorectal cancer

Genetic polymorphisms of cytokine genes may lead to variations in immunological response and genetic susceptibility to complex diseases that include cancer. Tumor necrosis factor-a (TNF-a) is an inflammatory cytokine that performs a crucial function in the immune reaction and may be involved in the development of colorectal cancer (CRC). There is evidence that genetic variations of the TNF-α gene increase susceptibility to CRC. We aimed to investigate the relationship between the TNF-α 308 G > A polymorphism, located in the TNF-α promoter region, and the risk of CRC. One hundred and eleven patients with CRC and 234 controls were recruited. DNA genotyping was undertaken using a Taqman® based assay. The frequency of the minor allele was approximately 0.2. The TNF-α-308G/A polymorphism was associated with an increased risk of CRC (Allele model (A vs. G), OR = 0.43, 95%CI = 0.26–0.71, p = 0.001; recessive model (AA+AG vs. GG), OR = 2.81, 95%CI = 1.60–4.93, p = 0.003; co-dominant model (AG vs. AA+GG), OR = 2.87, 95%CI = 1.60–5.14, p = 0.0004). Further investigations are required in more diverse populations to determine the value of this polymorphism as a risk stratification biomarker for CRC.