Spatial Principal Component Analysis (sPCA) based on frequencies of Y-chromosome haplogroups.

<p>The first two global components, sPC1 (a) and sPC2 (b), are depicted. Positive values are represented by black square; negative values are represented by white squares; the size of the square is proportional to the absolute value of sPC scores.</p

Age estimates (in YBP) of STR and HVS variation for the most common haplogroups in the Italian data set.

<p>Standard deviation (SD) estimator (Sengupta et al. 2006) and ñ statistic calculator (Soares et al. 2009) were used for Y-chromosome and mtDNA haplogroups respectively. Ages were estimated for the entire haplogroups as well as for each DAPC cluster with at least 10 individuals and frequencies >70% in NWI, SEI, or SAR (excepted for G-P15, cluster 2, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0065441#s2" target="_blank">Methods</a>).</p

Discriminant Analysis of Principal Components (DAPC) for G2a-P15 haplotypes.

<p>Samples are grouped according to their affiliation at the sPCA-identified groups (NWI; SEI; SAR; symbols in the top right table). The table in the bottom left shows the number of haplotypes in each of the five G2a clusters and their geographical distribution in the three Italian areas. DAPC eigenvalues are depicted in the enclosed barplot.</p