Figure 2 of Ryu, Mol Vis 2010; 16:2811-2821.


Figure 2. Population stratification in the age-related eye disease study (AREDS) subjects. Three race categories are presented in pink circle for white, non-Hispanics (White), in black triangle for blacks (Black), and in green cross for subjects who are neither white, non-Hispanics nor blacks. A plot of the first two principal components using 103,895 single nucleotide polymorphisms (SNPs) passing quality-control filters. Of the total 590 subjects, the self-reported race was white, non-Hispanic for 576, black for 12, and “other” for 2. The figure shows that one black subject and two other subjects were similar to the white subjects. There was also stratification among the white subjects, for which we corrected in subsequent analyses. The x-axis shows the first principal component axis (PC1), while the y-axis shows the second component (PC2).