What’s In Your Intestine?
Human Taxonomy, Medicine, Microbiology, Science, Taxonomy
Wired describes a newly published scientific paper offering a new form of human taxonomic classification. This development offers promise of assistance in treating gastrointestinal diseases and obesity and in more specifically personalizing medical treatment in general.
In much the same way that every person has one of eight common blood types, each of us may contain one of several possible bacterial communities, suggests new research. …
In the latest study [Published Apr. 21 in Nature], [Mani] Arumugam, fellow EMBL bionformaticist Peer Bork and dozens of other researchers sequenced every gene they could find in fecal samples from 22 people from Denmark, France, Italy and Spain. Then they searched the data for patterns, looking to see if certain arrangements of bacteria tended to be found in certain people.
The search returned three distinctive â€œenterotypes,â€ or bacterial communities dominated by a distinct genus â€” Bacteroides, Prevotella or Ruminococcus â€” each of which is found with a particular community of bacteria (see picture above).
â€œOne analogy that people draw â€” I donâ€™t know how accurate it is yet â€” is blood type,â€ said Arumugam. â€œItâ€™s not exactly the same. Blood types donâ€™t change, but we donâ€™t know if enterotypes do.â€
Further analysis of microbiomes from 13 Japanese and four Americans returned the same three clusters, suggesting the patterns are widespread and unconnected to ethnicity, age or gender. With such a limited sample size, however, containing no microbiomes from South Asia, Africa, South America and Australia, it remains to be seen whether other enterotypes exist.
Beyond identifying the enterotypes, â€œanything we say now will be a hypothesis,â€ said Arumugam. In terms of function, each of the enterotype-defining genera has been linked to nutrient-processing preferences â€” Bacteroides to carbohydrates, Prevotella to proteins called mucins, or Ruminococcus to mucins and sugars â€” but far more may be going on.
â€œExactly what they are doing in there is still to be explored,â€ said Arumugam.