Nrf2 gene promoter polymorphism is associated with ulcerative colitis in a Japanese population

Background/Aims: Transcription factor Nrf2 regulates the expression of detoxifying and antioxidant genes. Three promoter polymorphisms of this gene have been identified. This study attempted to clarify the relationship between Nrf2 gene polymorphism and ulcerative colitis in a Japanese population. Methodology: The study was performed in 89 patients with ulcerative colitis (mean age: 40.2 years, M:F=47:42) and 141 healthy volunteers (mean age: 38.7 years, M:F=75:66). The PCR-SSCP method was employed to detect Nrf2 polymorphisms using DNA extracted from peripheral blood cells. Results: Comparison of genotype frequency, -686·-684 A·G/A·G genotype was significantly lower in the UC group than those in the HC group (OR=0.45, 95%CI:0.22-0.93, p=0.029) and G·G carrier was higher in the UC group, especially in female subjects. Furthermore, -686·-684 G·G carrier was more closely associated with chronic continuous phenotype (OR=2.57, 95%CI:1.01-6.60, p=0.043). On the other hand, no association between -650 genotype and ulcerative colitis was found. Conclusions: The -686·-684 genotype of Nrf2 gene may be associated with the development of ulcerative colitis.