Causal link between gut microbiota and obsessive-compulsive disorder: A two-sample Mendelian randomization analysis.

Area of Science:

• Microbiome Research
• Psychiatric Genetics
• Human Health

Background:

• Emerging evidence suggests a link between gut microbiota and obsessive-compulsive disorder (OCD).
• The precise causal relationship between gut bacteria and OCD remains unclear.
• This study investigates the potential causal role of gut microbiota in OCD development.

Purpose of the Study:

• To evaluate the causal relationship between gut microbiota composition and obsessive-compulsive disorder (OCD).
• To identify specific gut bacteria that may act as risk or protective factors for OCD.
• To explore potential novel therapeutic targets for OCD based on gut microbiome modulation.

Main Methods:

• Utilized a two-sample Mendelian randomization (MR) analysis.
• Employed Genome-Wide Association Study (GWAS) summary data for gut microbiota (n=18,340) and OCD (n=199,169).
• Applied inverse variance weighting (IVW), MR Egger, and other methods, assessing heterogeneity and pleiotropy.

Main Results:

• Proteobacteria and Ruminococcaceae showed a protective effect against OCD.
• Bacillales, Eubacterium ruminantium group, and Lachnospiraceae UCG001 were identified as risk factors for OCD.
• No significant reverse causal relationship was found between OCD and gut microbiota.

Conclusions:

• Specific gut bacteria taxa are causally associated with obsessive-compulsive disorder (OCD).
• Findings suggest the gut microbiome as a potential target for OCD prevention and treatment.
• This research opens avenues for microbiome-based interventions in psychiatric disorders.