VANGAY, PAJAU2019-12-112019-12-112018-08https://hdl.handle.net/11299/209016University of Minnesota Ph.D. dissertation. August 2018. Major: Biomedical Informatics and Computational Biology. Advisor: Dan Knights. 1 computer file (PDF); x, 132 pages.Many United States immigrant populations develop metabolic diseases post-immigration, but the causes are not well understood. Although the microbiome plays a role in metabolic disease, there have been no studies measuring the effects of U.S. immigration on the gut microbiome. We collected stool, dietary recalls, and anthropometrics from 514 Hmong and Karen individuals living in Thailand and the U.S., including first- and second-generation immigrants and 19 Karen individuals sampled before and after immigration, as well as from 36 U.S.-born Caucasian individuals. Using 16S and deep shotgun metagenomic DNA sequencing, we found that migration from a non-Western country to the U.S. is associated with immediate loss of gut microbiome diversity and function, with U.S.-associated strains and functions displacing native strains and functions. These effects increase with duration of U.S. residence, and are compounded by obesity and across generations.enimmigrationmetagenomicsmicrobiomemicrobiotaobesityrefugee healthGut microbiome westernization in Hmong and Karen refugees and immigrants in the United StatesThesis or Dissertation