Bulky DNA adduct levels in normal-appearing colon mucosa, and the prevalence of colorectal adenomas

AbstractPurpose: Examine the association between bulky DNA adduct levels in colon mucosa and colorectal adenoma prevalence, and explore the correlation between adduct levels in leukocytes and colon tissue.Methods: Bulky DNA adduct levels were measured using 32P-postlabelling in biopsies of normal-appearing colon tissue and blood donated by 202 patients. Multivariable logistic regression was used to examine associations between DNA adducts, and interactions of DNA adduct-DNA repair polymorphisms, with the prevalence of colorectal adenomas. Correlation between blood and tissue levels of DNA adducts was evaluated using Spearman’s correlation coefficient.Results: An interaction between bulky DNA adduct levels and XPA rs1800975 on prevalence of colorectal adenoma was observed. Among individuals with lower DNA repair activity, increased DNA adduct levels were associated with increased colorectal adenoma prevalence (OR = 1.41 per SD increase, 95%CI: 0.92–2.18). Conversely, among individuals with normal DNA activ...