Identity-by-descent captures shared environmental factors at biobank scale.

Identity-by-descent-based clustering reveals environmental and health disparities at biobank scale, with 17 subcommunities showing differential exposure and disease prevalence.

• Why it matters: Understanding how shared environmental factors influence health beyond genetic ancestry can improve precision health strategies; current classifications may overlook these shared exposures.
• What they did: Using genomic and electronic health record data from 13,143 individuals, a hierarchical community detection algorithm identified 17 subcommunities based on shared IBD, integrating geographic and environmental data.
• The result: Subcommunities exhibit unequal environmental exposures and health outcomes, with persistent disparities even after adjusting for race, highlighting IBD-based clustering as a tool to capture genetic and environmental health determinants.