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Updated: Jul 14, 2026
11:22
Microbiota Analysis Using Two-step PCR and Next-generation 16S rRNA Gene Sequencing
Published on: October 15, 2019
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Causal relationships between gut microbiota and dementia: A two-sample, bidirectional, Mendelian randomization study
Zhao-Lin Ren1, Hai-Hong Zhou1, Chu-Pei Chen2
1Department of Neurology, The Affiliated Hospital of Guangdong Medical University, Zhanjiang 524000, Guangdong Province, China.
World Journal of Clinical Cases
|June 20, 2024
Summary
Gut microbiota may causally influence dementia risk. Specific bacterial orders, like Bacillales, show associations with Alzheimer's disease dementia, suggesting potential therapeutic targets for prevention and treatment.
Area of Science:
- Neuroscience
- Microbiology
- Genetics
Background:
- Gut microbiota is a recognized environmental risk factor for various dementias.
- Causal links between gut microbiota and dementia subtypes remain unclear.
Purpose of the Study:
- Investigate causal relationships between gut microbiota and dementia using Mendelian randomization (MR).
- Identify specific gut bacteria associated with dementia risk or protection.
Main Methods:
- Conducted a bidirectional, two-sample MR analysis.
- Utilized genome-wide association study (GWAS) data for gut microbiota and dementia from MiBioGen and FinnGen consortia.
- Employed five MR methods and Bonferroni correction for robust analysis.
Main Results:
- Identified gut taxa with putative causal links to dementia, acting as risk or protective factors.
- Reverse MR indicated dementia influences gut microbiota composition.
- The order Bacillales showed a significant association with Alzheimer's disease dementia (P-adjusted = 0.0311).
Conclusions:
- Gut microbiota is causally associated with dementia.
- Findings offer novel insights into dementia pathophysiology.
- Results have implications for dementia treatment and prevention strategies.
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