NOD2 and Crohn disease: Numerous genetic studies have identified three NOD2 polymorphisms rs2066844 (R702W), rs2066845 (G908R), and rs2066847 (1007fs) as being associated with increased susceptibility for Crohn’s disease, common to all three is a loss in MDP sensitivity and an inability to activated downstream targets, thus inducing an immunodeficiency in carriers (Burton et al., 2007; Franke et al., 2010).