PCA of TSI and samples representing main continental groups, including Africa (AFR; represented by YRI), East Asia (EAS; represented by CHB), broad Middle East (bMEA), and Europe (EUR; represented by CEU+GBR+IBS+SPA) (Figure 1A) and PCA comparing only TSI, EUR and different populations from bMEA (Figure 1B).

<p>For each PCA analysis, only three principal components are represented (PC1 <i>vs.</i> PC2, and PC1 <i>vs.</i> PC3). See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0105920#pone-0105920-t001" target="_blank">Table 1</a> for more information on population codes.