The causality between gut microbiota and ankylosing spondylitis: Insights from a bidirectional two-sample Mendelian...

Area of Science:

• Genetics
• Microbiology
• Immunology

Background:

• The relationship between gut microbiota and ankylosing spondylitis (AS) is suggested but not clearly established.
• Investigating this link is crucial for understanding AS pathogenesis.

Purpose of the Study:

• To determine the causal relationship between gut microbial composition and ankylosing spondylitis (AS) using a robust genetic approach.
• To identify specific gut bacteria that may influence AS risk.

Main Methods:

• A two-sample Mendelian randomization (MR) study utilized single nucleotide polymorphisms (SNPs) associated with gut microbiome and AS.
• Genome-wide association study data from 968 AS cases and 336,191 controls were analyzed.
• Inverse-variance weighted method was employed to estimate causal effects, with sensitivity analyses confirming robustness.

Main Results:

• Certain bacteria, including Anaerotruncus and Ruminococcaceae UCG002, showed a protective effect against AS.
• Conversely, Defluviitaleaceae, Butyricicoccus, Coprococcus 3, and Defluviitaleaceae UCG011 were associated with increased AS susceptibility.
• Reverse MR analysis indicated that AS does not influence gut microbial composition.

Conclusions:

• A genetically supported causal relationship between gut microbiota and AS has been established.
• These findings suggest potential therapeutic strategies targeting specific gut bacteria for AS prevention and treatment.