These bacteria, which form what is known as the gut microbiota, have true physiological and immunological functions and in this respect are often considered to be a separate organ.

The European MetaHIT project, launched in 2008, has as its goal the study of the genome (the set of genetic material) of these bacteria in order to understand their functions, especially in pathologies. In an article published in April in the revue Nature(1), scientists from the MetaHit consortium studied the composition of these microbiota and its genome in 22 persons of European origin. They concluded that these persons can be classified into three categories, or which they call “enterotypes” as a function of the type of bacteria found and its function. They also indicate that these enterotypes do not have any geographic specificity, in comparison with two other Japanese and American cohorts.

The authors explain that these enterotypes could explain the individual differences observed during the response to medical treatment or absorption of certain foods. According to the authors, such enterotypes, and in particular their functions, could be used in diagnosis and prognosis of pathologies such as colorectal cancers, diabetes and cardiovascular diseases.

Par Cécile Vignal

References

Arumugam, M., et al., Enterotypes of the human gut microbiome. Nature.473(7346): p. 174-80.