Figure 1.

Schematic of how a disease locus will appear in an admixture scan. Around the locus, there should be an unusually high proportion of ancestry from one of the parental populations, because of patients inheriting high-risk alleles from that group. The peak can be identified not only in a case-control comparison but also in a comparison of the estimate of ancestry in cases at that point in their genome with the rest of their genomes. The width of the peak of association is determined by the number of generations since admixture.