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

Figure 1

Relationship between MHC gene variants and gut dysbiosis and some. (a) A variant in the MHC gene is associated with the inability of the immune system to recognize self-antigens, thereby attacking them and progressing to the development of autoimmune diseases such as T1D, IBD, RA, UC, and CD. This pathway is independent of gut microbiota. (b) The MHC gene is involved in the production of IgA, and a genetic variant in the gene is shown to result in defective IgA production. As the most common immunoglobulin in the gut, defective IgA results in a poor clearance of gut pathogens which eventually develop into gut dysbiosis. Dysbiosis was described to contribute to the development of autoimmune diseases. (c) Lastly, similar to the inability to recognize self-antigens, the gene variant is also associated with the inability to recognize the antigens of gut commensals. This eventually led to the attacking of the commensals and resulting in gut dysbiosis. The dysbiosis developed in this case is also known to be involved in the development of autoimmune diseases.