The interpersonal and intrasubject diversity of human-associated microbiota in key body sites

Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO, USA.
The Journal of allergy and clinical immunology (Impact Factor: 11.48). 05/2012; 129(5):1204-8. DOI: 10.1016/j.jaci.2012.03.010
Source: PubMed


The human body harbors 10 to 100 trillion microbes, mainly bacteria in our gut, which greatly outnumber our own human cells. This bacterial assemblage, referred to as the human microbiota, plays a fundamental role in our well-being. Deviations from healthy microbial compositions (dysbiosis) have been linked with important human diseases, including inflammation-linked disorders, such as allergies, obesity, and inflammatory bowel disease. Characterizing the temporal variations and community membership of the healthy human microbiome is critical to accurately identify the significant deviations from normality that could be associated with disease states. However, the diversity of the human microbiome varies between body sites, between patients, and over time. Environmental differences have also been shown to play a role in shaping the human microbiome in different cultures, requiring that the healthy human microbiome be characterized across life spans, ethnicities, nationalities, cultures, and geographic locales. In this article we summarize our knowledge on the microbial composition of the 5 best-characterized body sites (gut, skin, oral, airways, and vagina), focusing on interpersonal and intrapersonal variations and our current understanding of the sources of this variation.

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Available from: Dirk Gevers, Dec 15, 2013
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    • "Le microbiote cutané est principalement dominé par les 4 phyla Proteobacteria, Firmicutes, Actinobacteria et Bacteroidetes en proportions relatives variables selon les sites [33] [34] [35]. Il semble que ce microbiote fasse partie des plus complexes et diversifiés du corps humain, avec des variabilités interindividuelles très élevées [13] [36] [37] [38]. Il en résulte la difficulté de définir le « core microbiome » de la peau, comme pour d'autres microbiotes [13] [39]. "
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    • "Almost all clinical studies with microbial therapies are carried out with people from developed countries.[789] Since, there is a variety in gut flora between different world's regions[1314] the efficacy of probiotics may be affected by different ethnic groups of patients from different countries. There is no published report about probiotics efficacy on IBS treatment in Iran yet. "
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    • "hat may affect medications in many more complex ways than the human genome variations do ( Rizkallah et al . , 2010 ) . Microbiome variations do not merely occur between individuals , but , as suggested above , can be spatial , temporal , seasonal , developmental , hormonal , dietary , or drug - dependent within the same individual ( Aziz , 2012 ; Ursell et al . , 2012 ) . Below we discuss examples of intra - individual variations that shape the microbiome struc - ture , and we demonstrate how the concept of a microbiome cloud complicates cataloguing human microbiome varia - tions , their classification into clusters or biome types , and the definition of a universal / core human microbiome ."
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