NOD2 and Crohn disease: Studies by our group and that of Warner’s, respectively, identified 17 and 15 genes associated with Crohn’s disease risk are, in fact, regulators of NOD2-NF-κB signalling (Supplementary Data 1); however, only two Crohn’s disease risk genes were common between both studies, highlighting the need for multiple such studies to determine the function of candidate Crohn’s disease susceptibility genes.