Human Microbiome Project (HMP)
Within the body of a healthy adult, microbial cells are estimated to outnumber human cells by a factor of ten to one. These communities, however, remain largely unstudied, leaving almost entirely unknown their influence upon human development, physiology, immunity, and nutrition. To take advantage of recent technological advances and to develop new ones, the NIH Roadmap has initiated the Human Microbiome Project (HMP) with the mission of generating resources enabling comprehensive characterization of the human microbiota and analysis of its role in human health and disease.
Traditional microbiology has focused on the study of individual species as isolated units. However many, if not most, have never been successfully isolated as viable specimens for analysis, presumably because their growth is dependant upon a specific microenvironment that has not been, or cannot be, reproduced experimentally. Among those species that have been isolated, analyses of genetic makeup, gene expression patterns, and metabolic physiologies have rarely extended to inter-species interactions or microbe-host interactions. Advances in DNA sequencing technologies have created a new field of research, called metagenomics, allowing comprehensive examination of microbial communities, even those comprised of uncultivable organisms. Instead of examining the genome of an individual bacterial strain that has been grown in a laboratory, the metagenomic approach allows analysis of genetic material derived from complete microbial communities harvested from natural environments. In the HMP, this method will complement genetic analyses of known isolated strains, providing unprecedented information about the complexity of human microbial communities.
By leveraging both the metagenomic and traditional approach to genomic DNA sequencing, the Human Microbiome Project will lay the foundation for further studies of human-associated microbial communities. Broadly, the project has set the following goals:
- Determining whether individuals share a core human microbiome
- Understanding whether changes in the human microbiome can be correlated with changes in human health
- Developing the new technological and bioinformatic tools needed to support these goals
- Addressing the ethical, legal and social implications raised by human microbiome research.
Notably, however, the utility of the techniques and technologies pioneered by the HMP will not be limited to studies of human health but will be applicable to the study of microbes in a wide range of biological processes. Microbes profoundly shape this planet and all life on it, and yet the test tube of the laboratory is rarely reflective of how they actually exist in the environment. The ability to study native microbial communities represents a fundamental shift in microbiology and is one whose implications can only be imagined.
Finally, the NIH Human Microbiome Project is only one of several international efforts designed to take advantage of metagenomic analysis to study human health. The HMP expects to continue the practice established by the Human Genome Project of international collaboration to generate a rich, comprehensive, and publicly available data set. This information will be available worldwide for use by investigators and others in efforts to understand and improve human health. For more information on the Human Microbiome Project, e-mail HMPinformation@mail.nih.gov or visit http://www.hmpdacc.org.