East Asians experience worse metabolic health outcomes compared to other ethnic groups at lower body mass indices; however, the potential role of the gut microbiota in contributing to these health disparities remains unknown. We conducted a multi-omic study of 46 lean and obese East Asian and White participants living in the San Francisco Bay Area, revealing marked differences between ethnic groups in bacterial richness and community structure. White individuals were enriched for the mucin-degrading Akkermansia muciniphila. East Asian subjects had increased levels of multiple bacterial phyla, fermentative pathways detected by metagenomics, and the short-chain fatty acid end-products acetate, propionate, and isobutyrate. Differences in the gut microbiota between the East Asian and White subjects could not be explained by dietary intake, were more pronounced in lean individuals, and were associated with current geographical location. Microbiome transplantations into germ-free mice demonstrated stable diet- and host genotype-independent differences between the gut microbiotas of East Asian and White individuals that differentially impact host body composition. Taken together, our findings add to the growing body of literature describing variation between ethnicities and provide a starting point for defining the mechanisms through which the microbiome may shape disparate health outcomes in East Asians.
All 16S-seq and metagenomic sequencing data generated in the preparation of this manuscript have been deposited in NCBI's Sequence Read Archive under accession number PRJNA665061. Metabolomics results and metadata are available within this manuscript (Tables S2, S4, S5, and S9). Code for our manuscript will be uploaded to GitHub (https://github.com/turnbaughlab/2021_IDEO).
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: Protocols for all experiments involving mice were approved by the University of California, San Francisco Institutional Animal Care and Use Committee, and performed accordingly (UCSF IACUC numbers AN183950 and AN184143).
Human subjects: Informed consent was provided for all subjects participating in the study, which was approved by the UCSF Institutional Review Board.
© 2021, Ang et al.
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