metagenome

A MAP OF DIVERSITY IN THE HUMAN MICROBIOME

Over the course of our lives, humans are colonized by a tremendous diversity of commensal microbes, which comprise the human microbiome.

The human microbiome is dominated by four phyla: Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria.

The collective genetic potential (metagenome) of the human microbiome is orders of magnitude more than the human genome, and it profoundly affects human health and disease in ways we are only beginning to understand.

Source:  Trends in Genetics,  Volume 29, Issue 1, January 2013

Biodiversity and functional genomics in the human microbiome
by Xochitl C. Morgan, Nicola Segata, Curtis Huttenhower.

HOW TO READ THE MAP

  • In the center is a phylogenetic tree of organisms abundant in the human microbiome. Commensal microbes are indicated by circles, and potential pathogens are indicated by stars.
  • The middle ring corresponds to body sites at which the various taxa are abundant and is color-coded by site [e.g., Ruminococcus (blue) is found mostly in the gut, whereas Lactobacillus (purple) is found mostly in the vagina].
  • The bar heights on the outside of the circle are proportional to taxa abundance at the body site of greatest prevalence [e.g., Streptococcus mitis (yellow) dominates the inside of the cheek, whereas the gut is abundant in a variety of Bacteroides].
  • The intensity of external colors corresponds to species prevalence in each body site.

My gut microbiome is better than yours…maybe.. who knows right now. Based on 22 faecal metagenomes from four countries scientists from the Metagenomics of the Human Intestinal Tract (MetaHIT) Consortium have identified three robust gut microbiome types. Their person specific association and effect on health and development is still not clear, but it is a really cool finding in gut metagenome research.