Properties of global- and local-ancestry adjustments in genetic association tests in admixed populations.

ABSTRACT: Population substructure can lead to confounding in tests for genetic association, and failure to adjust properly can result in spurious findings. Here we address this issue of confounding by considering the impact of global ancestry (average ancestry across the genome) and local ancestry (ancestry at a specific chromosomal location) on regression parameters and relative power in ancestry-adjusted and -unadjusted models. We examine theoretical expectations under different scenarios for population substructure; applying different regression models, verifying and generalizing using simulations, and exploring the findings in real-world admixed populations. We show that admixture does not lead to confounding when the trait locus is tested directly in a single admixed population. However, if the

SUBMITTER: Martin ER 

PROVIDER: S-EPMC5811405 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature