Fig. 3

Evaluation of PTESHK. a Linear graph depicted the detection ability of 89 Chinese fixed loci using PTESHK. In all the samples, no less than 86 HERV-K (HML-2) fixed loci can be detected. b Box plot exhibiting the correlation between the average CPM of HERV-K (HML-2) loci in all 9 samples and the corresponding estimated age (Mya). As the figure shows, the more recent the HERV-K (HML-2) integration, the higher the average RPTM. These results show that it is much easier to detect recently integrated loci. c–e Venn diagram exhibiting the interrelationship among the detected loci of experimental replicates of different individuals. Within the three replicates of “P”, 872 loci could be detected in all the repeats, whereas in “W” and “Y”, there were 889 and 886 repeatable loci. f–h Correlation analysis of the relative abundance (CPM value) of the same locus in different replicates. Grids on the diagonal line of the figure represent the replicates and exhibit the distribution of the CPMs. In the upper half of the figure, the grid of intersection of the row of one sample and the column of another sample represents the Pearson correlation coefficient between the two samples and shows a significant correlation of the CPM of different samples. In the bottom half of the figure, the nearly linear correlation represents the relationship of the RPTM between every two samples