Host genomic variation shapes gut microbiome diversity in threespine stickleback fish

Area of Science:

• Microbiology
• Genetics
• Ecology

Background:

• Understanding host genetic influence on the microbiome is crucial but challenging due to environmental variables.
• Previous studies lacked strict control over environmental factors, hindering the isolation of host genetic effects.

Purpose of the Study:

• To investigate the impact of host genetic variation on microbiome composition in a controlled environment.
• To establish a model system for studying host-microbiome interactions using genetically diverse hosts.

Main Methods:

• Utilized stickleback fish (Gasterosteus aculeatus) in a common garden experiment with standardized early-life microbiomes.
• Controlled environmental factors rigorously, allowing unrestricted co-housing of genetically distinct fish.
• Analyzed over 2,000 host genomic regions and correlated genetic variation with microbiome composition.

Main Results:

• Host genetic differences were shown to significantly influence microbiome diversity and composition.
• The experimental design successfully isolated genetic effects from environmental influences.
• A clear link was established between specific host genomic regions and microbial community structure.

Conclusions:

• Host genetics play a critical role in shaping the microbiome, even under highly controlled environmental conditions.
• Stickleback fish provide a powerful model for dissecting host-microbiome interactions.
• Future research should leverage genetically variable host systems for manipulative microbiome studies.