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Microbiota Analysis Using Two-step PCR and Next-generation 16S rRNA Gene Sequencing

Microbiota Analysis Using Two-step PCR and Next-generation 16S rRNA Gene Sequencing

Published on: October 15, 2019

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.

Keywords:

Alzheimer’s disease Dementia FinnGen Gut microbiota Mendelian randomization MiBioGen Vascular dementia

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Last Updated: Jul 14, 2026

Microbiota Analysis Using Two-step PCR and Next-generation 16S rRNA Gene Sequencing

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High-Throughput Screening of Microbial Isolates with Impact on Caenorhabditis elegans Health

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Murine Fecal Isolation and Microbiota Transplantation

Murine Fecal Isolation and Microbiota Transplantation

Published on: May 26, 2023

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.