RAPH1 and colitis: In mice the adaptor protein RAPH1 has recently been shown to play an important Treg-specific role in integrin activation, Treg-suppressive function and Treg homing to the gut in a mouse model of colitis [45] suggesting changes in RAPH1 expression associated with regulatory regions harbouring variants rs231775 and rs3087243 may contribute to Treg defects in humans.