IL23R and Crohn disease: As for IL23R polymorphisms, a study by Lappalainen et al. [15] demonstrated that IL23R polymorphisms (rs1004819, 10889677, rs2201841, rs11465804, and rs11209026) increased Crohn’s disease (CD) susceptibility in a Finnish population, while another study revealed that an association of IL23R with UC, but not with CD in Swedish patients [16].