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Oral Microbiome and Constipation: A Causal Link Revealed by Mendelian Randomization
Ziyi Zhao1, Jinlian Ling1, Jiashu Chen2
1Faculty of Biology, Medicine and Health University of Manchester UK.
Summary
This study explored the oral microbiome
Area of Science:
- Microbiome research
- Human genetics
- Gastroenterology
Background:
- Constipation affects over 15% of the global population.
- The gut microbiome's role in constipation is known, but the oral microbiome's influence is unexplored.
- Investigating the oral microbiome's causal link to constipation is crucial for understanding gastrointestinal health.
Purpose of the Study:
- To investigate the potential causal relationship between the oral microbiome and constipation.
- To identify specific oral bacteria associated with constipation risk.
- To explore the implications for gastrointestinal health management.
Main Methods:
- Utilized Mendelian randomization (MR) with large-scale genome-wide association study (GWAS) data.
- Oral microbiome data from a metagenome-wide association study (mgGWAS) of 2984 individuals.
- Constipation GWAS data from 176,629 samples in the Japan Biobank; employed IVW, weighted median, and MR-Egger regression.
Main Results:
- Identified significant associations between specific oral bacteria and constipation.
- Treponema denticola (saliva) showed a positive association with constipation risk (OR=3.961, p=0.037).
- Neisseria sicca (tongue coating) was positively associated with constipation (OR=4.864, p=0.019), while Pauljensenia sp000308055 and Aggregatibacter segnis showed protective effects.
Conclusions:
- This is the first study to explore the causal link between the oral microbiome and constipation.
- Specific oral bacteria may influence constipation risk, warranting further mechanistic research.
- Highlights the importance of considering both oral and gut microbiomes in gastrointestinal health.
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