Plots representing the genetic relationships among the 31 tribal and non-tribal populations of Tamil Nadu.

<p>(A) PCA plot based on HG frequencies. The two dimensions display 36% of the total variance. The contribution of the first four HGs is superimposed as grey component loading vectors: the HTF populations clustered in the direction of the F-M89 vector, HTK in the H1-M52 vector, BRH in the R1a1-M17 vector, while the HG L1-M27 is less significant in discriminating populations. (B) MDS plot based on 17 microsatellite loci <i>R_st</i> distances. The two tribal groups (HTF and HTK) are clustered at the left side of the plot while BRH form a distant cluster at the opposite side. The colors and symbols are the same as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0050269#pone-0050269-g001" target="_blank">Figure 1</a>, while population abbreviations are as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0050269#pone-0050269-t001" target="_blank">Table 1</a>.