Relationship Between eNOS T-786C and G894T Polymorphisms and Colorectal Cancer Susceptibility: A Study in the Algerian Population

Colorectal cancer (CRC) is a multifactorial disease influenced by genetic and environmental factors. The endothelial nitric oxide synthase (eNOS) gene, involved in nitric oxide (NO) production, is associated with carcinogenesis. This study aimed to evaluate the association between eNOS −786T>C and G894T polymorphisms and CRC susceptibility in an Algerian population. Genotype and allele frequencies were analyzed, and associations were assessed using odds ratios (ORs) and 95% confidence intervals (CIs). For −786T>C polymorphism, the CC genotype was significantly more frequent in patients than in controls (37.33% vs. 21.67%) and was associated with increased risk of CRC (OR = 2.15, 95% CI: 1.21–3.88, p = 0.004), whereas the TT genotype showed a protective effect (OR = 0.41, 95% CI: 0.20–0.81, p = 0.005). Regarding the G894T polymorphism, the TT genotype was significantly associated with increased susceptibility to CRC (44.67% vs. 8.33%; OR = 8.88, 95% CI: 4.19–15.40, p < 0.001), while the GG genotype was protective (OR = 0.18, 95% CI: 0.10–0.32, p < 0.001). Allelic analysis confirmed that the C and T alleles were risk factors. Furthermore, eNOS polymorphisms were significantly associated with tumor location. In conclusion, the eNOS −786T>C and G894T polymorphisms are significantly associated with CRC susceptibility in the Algerian population and could serve as potential genetic biomarkers.