In admixed populations, individual genomes can be viewed as mosaics of ancestry segments, with different segments arising from different “parental” populations that participated in an admixture process. Admixed populations often have high variation across individuals in the proportions of ancestry from the various source groups70,71,72, and in the same way that use of multiple subgroups of a larger population in an association study can give rise to false-positive associations, variation in admixture proportions can also produce spurious association of genotypes and phenotypes through their separate associations with ancestry73.
