The All of Us Research Program, affiliated with the National Institutes of Health, seeks to advance biomedical research and address the underrepresentation of non-White Americans in genetic research. The program is currently working on recruiting over 1 million participants to measure the country’s genetic variation.
Recently, a new report using All of Us data has found self-reported race and ethnicity do not always match genetic ancestry, suggesting that specific, subcontinental genetic ancestry data may be a better method of understanding and addressing the persistent health disparities between different populations in the United States.
Led by scholars at the National Human Genome Research Institute, the research team analyzed some 2 million genetic variants in the genomes of more than 230,000 participants included in the All of Us database. According to the authors, this study is the largest population genomics analysis of U.S. samples that reflect the nation’s genetic variation.
In their analysis, the authors found participants within the same self-identified race and ethnicity groups had gradients of genetic variation rather than discrete clusters, with Black and African American participants reflecting varying degrees of African and European ancestry. Furthermore, the authors found local categories within continents provided important insights into how genetic traits are shaped. For example, West-Central African and East African ancestries – which are frequently grouped together as African ancestry – had different associations with BMI levels, with West-Central African traits showing higher BMI and East African traits showing lower BMI.
“Our results and previous reports highlight the importance of avoiding using African continental ancestry as a single entity,” the authors write. “Given this consideration and the well-documented subcontinental ancestries within Africa, the Americas, Asia, and Europe, along with their substantial regional variation within continents and in the US, we recommend treating continental ancestry not as a singular entity but as a composite of subcontinental ancestries.”
However, the authors also highlight the importance of including race and ethnicity in other areas of research, stating that although they may be inadequate in “defining genetically or biologically distinct populations,” they “may serve as proxies for capturing sociocultural or environmental factors that are not typically accounted for by standard covariates in association models.”
