Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, United States; Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, United States; McGill Genome Centre, McGill University, Montreal, Canada; Department of Human Genetics, McGill University, Montreal, Canada
Division of General Internal Medicine, University of California, San Francisco, San Francisco, United States; Department of Medicine, University of California, San Francisco, San Francisco, United States; Institute of Human Genetics, University of California, San Francisco, San Francisco, United States; Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, United States
McGill Genome Centre, McGill University, Montreal, Canada; Department of Human Genetics, McGill University, Montreal, Canada
Dara G Torgerson
McGill Genome Centre, McGill University, Montreal, Canada; Department of Human Genetics, McGill University, Montreal, Canada; Department of Epidemiology and Biostatistics University of California, San Francisco, San Francisco, United States
Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, United States; McGill Genome Centre, McGill University, Montreal, Canada; Department of Human Genetics, McGill University, Montreal, Canada; Institute of Human Genetics, University of California, San Francisco, San Francisco, United States; Bakar Computational Health Sciences Institute, University of California, San Francisco, San Francisco, United States; Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, United States
People in the Americas represent a diverse continuum of populations with varying degrees of admixture among African, European, and Amerindigenous ancestries. In the United States, populations with non-European ancestry remain understudied, and thus little is known about the genetic architecture of phenotypic variation in these populations. Using genotype data from the Hispanic Community Health Study/Study of Latinos, we find that Amerindigenous ancestry increased by an average of ~20% spanning 1940s-1990s in Mexican Americans. These patterns result from complex interactions between several population and cultural factors which shaped patterns of genetic variation and influenced the genetic architecture of complex traits in Mexican Americans. We show for height how polygenic risk scores based on summary statistics from a European-based genome-wide association study perform poorly in Mexican Americans. Our findings reveal temporal changes in population structure within Hispanics/Latinos that may influence biomedical traits, demonstrating a need to improve our understanding of admixed populations.
