Nature vs. Nurture: The Gut Microbiome and Genetics in the Development of Gastrointestinal Disease

Emerging investigation into the physiologic role of the gut microbiome continues to yield new evidence for significant microbial influence across numerous gastrointestinal diseases. Integrating this new knowledge with the existing understanding of disease pathogenesis will be a critically important aspect of medicine in the near future. Furthermore, the gut microbiome and host genetics likely share significant functional overlap, the extent of which we are only beginning to understand. For instance, evidence suggests that starting even before birth the gut microbiome influences immune system development. In the early years of life, the gut microbiome also functions to establish proper metabolic functions of the gastrointestinal tract. Alterations of the normal gut microbiome can even lead to disease development in infancy and early childhood. Later in life, dysbiosis has been shown to be a commonality in inflammatory bowel disease, potentially serving an etiologic role as well. More importantly, there appears to be a significant interaction between the gut microbiome and certain genetic polymorphisms in inflammatory bowel disease, which may help to identify future therapeutic targets. Lastly, the scope of the gut microbiome continues to expand as we discover other microbial inhabitants such as archaea, fungi, and viruses, which all likely influence both normal gastrointestinal function and disease pathogenesis.