The human microbiome: Role in health and disease and its potential applications

Abstract

The human microbiota comprises all microorganisms living within the human body and microbiome is their collective genome. They include eukaryotes, archaea, bacteria and viruses. Most microbes live in the gut, particularly in the large intestine. The number of genes contributed to by the microbes is 100 times the number of genes in the human genome. The sheer microbial abundance suggests that the human body is a collection of human and microbial cells and their genes resulting in a blend of human and microbial traits. The microbiome is essential for maintenance of human life. The microbes that live in and on us are mostly beneficial colonizers and have many important functions such as assisting in digestion, regulating immune system, producing essential vitamins and protecting against bacteria that cause diseases. Research has demonstrated that dysbioses in the human microbiome correlate with numerous disease states, including inflammatory bowel disease, malignancy and autoimmune diseases. The metagenome of the human microbiome, the total DNA content of microbes inhabiting our bodies shows a large degree of interpersonal diversity. With the advent of culture-independent techniques such as high throughput next generation sequencing of DNA and advances in computational biology, research on human microbiome has reached new heights. A breakthrough in research was the development of Human Microbiome Project (HMP), which was established in 2008, which is also known as the second human genome project, with the objective of generating a metagenomic reference database for “normal” individuals to serve as a resource for researchers. The introduction of new technologies has permitted the study of the functional component of the microbe–host interactions through metabolomics. The resultant biomarkers have been used to predict and diagnose diseases early. Future research should focus on understanding mechanisms responsible for pathology and the causality role of the microbiome to use them as therapeutic modalities .