SELENON and adenoma: Up-regulation of GPX1 and SELENOH (p = 0.001 for both genes), and down-regulation of SELENON (p = 0.001) were demonstrated in the Czech patients, but no significant changes in the expression levels of these genes were found in the Irish cohort (although SELENOH was significantly more highly expressed in the adenoma tissue from the Irish CRA patients, p < 0.001).