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Published on: July 4, 2018
Global diversity in the human salivary microbiome
Ivan Nasidze1, Jing Li, Dominique Quinque
1Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany.
Genome Research
|March 3, 2009
Summary
The human salivary microbiome is highly diverse within and between individuals, with minimal geographic structuring. Understanding this diversity is key to its role in oral health and human population studies.
Area of Science:
- Microbiology
- Human Genetics
- Oral Health
Background:
- The human salivary microbiome's role in oral health and its interaction with other body microbiomes is largely unknown.
- Normal variation in the salivary microbiome requires further investigation.
Purpose of the Study:
- To analyze the diversity and structure of the human salivary microbiome across different global locations.
- To identify novel bacterial genera within the oral cavity.
Main Methods:
- Analysis of 14,115 partial 16S ribosomal RNA (rRNA) gene sequences from saliva samples.
- Samples were collected from 120 healthy individuals across 12 worldwide locations.
- Phylogenetic analysis was used to identify known and unknown bacterial genera.
Main Results:
- 101 known bacterial genera were identified, with 39 previously unreported in the human oral cavity.
- Phylogenetic analysis suggested the presence of an additional 64 unknown genera.
- High intra- and inter-individual diversity was observed, with limited geographic structure. Individual differences accounted for ~13.5% of the variance.
- A significant association was found between geographic distance from the equator and genetic distances among locations.
Conclusions:
- The human salivary microbiome exhibits substantial diversity, with individual variation being a major factor.
- Geographic location, particularly distance from the equator, may influence salivary microbiome composition.
- Further characterization is crucial for understanding the salivary microbiome's role in health, disease, and human population history.
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