Two histograms of Mahalanobis distances (D2s) to the centroid of the European-American (“White”) group. Both histograms display the same data, but with different axis ranges and bin widths. Histogram A uses bins of width 42 so that the first two bars on the left include all 6,615 White subjects and no others. The subjects with D2 near 1000 are mostly mixed-race, Hispanic and Native American. The peak between 3000 and 4000 was caused by 378 Asian subjects, mostly Korean adoptees, and the subjects with D2 exceeding 4000 are Black. Histogram B used bin widths of 1 so that all visible bars (values less than 84 on the abscissa) represent counts of White subjects. All subjects with D2 less than 84 were used in the core European American group for all initial GWAS analyses.
