aDNA and you may Polygenic Chance Get Framework.
We collected published aDNA data from 1,071 ancient individuals, taken from 29 publications. The majority of these individuals had been genotyped using an in-solution capture reagent (“1240k”) that targets 1.24 million SNPs across the genome. Because of the low coverage of most of these samples, the genotype data are pseudohaploid. That is, there is only a single allele present for each individual at each site, but alleles at adjacent sites may come from either of the 2 chromosomes of the individual. For individuals with shotgun sequence data, we selected a single read at each 1240k site. We obtained the date of each individual from the original publication. Most of the samples have been directly radiocarbon dated, or else are securely dated by context. ST using smartpca v16000 (79) (SI Appendix, Table S1) and multidimensional scaling using pairwise distances computed using plink v1.90b5.3 (options-distance flat-missing 1-ibs) (80) (SI Appendix, Fig. S1C) and unsupervised ADMXITURE (81) (SI Appendix, Fig. S1D).