Zooming in on the Microbiome

Tiny passengers inside the human body may hold the key to improving human health.

The human body is home to trillions of microorganisms that make up the human microbiome. In fact, recent estimates suggest that there are roughly as many bacterial cells in the human body as there are human cells. While scientists have been aware of the human microbiome for decades, until recently very little was understood about its importance to human health and disease. Today, the microbiome is a thriving area of biological research, and over the last few years it is has become clear that it plays a critical role in the development and possible treatment of numerous chronic diseases, including diabetes, obesity, and cancer.

In 2007, the IRP established the Human Microbiome Project (HMP) with the goal of developing resources to accelerate the study of the human microbiome and increase our understanding of its role in development, nutrition, disease, and human health. By the end of 2017, HMP investigators had published over 650 scientific papers, which had been cited over 70,000 times. As a result of this ground-breaking initiative, the NIH sequenced the genomes of more than 2,000 strains of bacteria across five different areas of the human body, launched 15 studies examining the relationship between the microbiome and human ailments such as cancer and Crohn’s disease, and created a variety of new methods and publicly available resources to aid in the study of the microbiome. With the launch in 2014 of the HMP’s second phase, the Integrative Human Microbiome Project (iHMP), the endeavor has begun to focus on tracking changes in the microbiome over time and their associations with human health and illness.

Since the establishment of the HMP, investment in microbiome research across the IRP has increased over forty-fold and now spans more than 20 IRP institutes and centers. Today, IRP researchers are uncovering new and exciting links between the microbiome and human health, from understanding the emerging connection between the microbiome and cancer to exploring the role of the microbiome in the development and maturation of the immune system and how the disruption of our microflora can lead to infections or autoimmune conditions.

By combining the efforts of experts across immunology, immunotherapy, microbial and human genomics, and animal model systems, the IRP is poised to continue to dramatically improve our understanding of the microbiome and uncover how it can be used to advance the biomedical field. Capitalizing on our synergistic approach to research, the IRP aims to address fundamental questions about the microbiome by:

  • Continuing to map the microbiome to gain an understanding of the microorganisms that are present in healthy and disease states
  • Illuminating the mechanisms through which the microbiome influences bodily processes, such as inflammation immune function, and digestion
  • Increasing investment into germ-free facilities to enable more detailed studies on the microbiome
  • Using whole-genome sequencing to track the evolution of drug-resistant pathogens

Explore these pages for more information about the past, present, and future of IRP microbiome research:

Check out all 12 of the domains in which we are Accelerating Science to learn about how IRP scientists are tackling important biomedical challenges.

This page was last updated on Wednesday, January 12, 2022