Gut Microbiome: An Intersection between Human Genome, Diet, and Epigenetics

Figure 2

Relationship between NOD2 gene variant and gut microbiota. (a) The NOD2 gene is crucially involved in the PRR system, and a genetic variant in the gene has been associated with ineffective clearance of gut pathogens, resulting in gut dysbiosis that contributes to the development of IBD. (b) The development of a defective mucosal layer is linked to a genetic defect of the NOD2 gene. Consequently, the gut is easily colonized by pathogens and progresses to gut dysbiosis which is associated with the development of colitis. (c) The abundance of Bacteroides species is often connected to the NOD2 gene variant. The bacteria is known to increase the expression level of IFN-γ. This inflammasome activates pathways that clear both commensals and pathogens from the gut and cause gut dysbiosis.