Selenium deficiency frequently occurs in IBD and was found to be inversely associated with disease activity.52,53 Interactions between serum selenium and 29 SNPs in selenoprotein coding genes or genes controlling selenium synthesis were investigated in the cohort of 351 CD patients and 853 controls from New Zealand.54 Of these, 13 were found to significantly interact with selenium on the risk of CD. Here, SELENOS is linked to selenium deficiency.