Hidden structure in polygenic scores and the challenge of disentangling ancestry interactions in admixed populations.

ABSTRACT: The extent to which genetic effects vary across ancestries remains a central question in human genetics, with direct implications for improving polygenic prediction. Recent studies have found that average causal effects are similar across ancestries, but empirical evidence and theoretical considerations suggest that interactions may still contribute to poor portability of polygenic scores. Here, we leverage the ancestry mosaicism of admixed individuals to develop models of genetic interactions with local and global ancestry. We show that these models capture epistasis but are also consistent with highly similar average causal effects, clarifying that the latter observation does not exclude the possibility of gene-ancestry interaction. Next, we investigate how models of local and global int

SUBMITTER: Aw AJ 

PROVIDER: S-EPMC12693580 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature