The Selection Of Tibetan Ancestry Informative SNPs And Forensic DNA Geographical Ancestry Inference

Objective:Select ancestry informative SNPs of Tibetan population and develop a multiplex system and algorithm to infer geographical ancestry of unknown individuals.Methods:We selected 44 Tibetan ancestry informative SNPs after analyzing 146 SNPs distribution in 1506 individuals from 15 East Asian populations.The F_ST and?value were used to evaluate the informativeness of SNPs.The original 146 SNPs panel used in this study include 87 SNPs from gene EGLN1 and EPAS1,59 SNPs from GWAS?Genome-Wide Association Study?.The 15 East Asian populations were consisted by 5populations?N=504?from 1000 Genomes Project database and 10 populations?N=1002?from Caixia Lab.STRUCTURE and PCA were employed to evaluate the population differentiation power of the 44 SNPs.Meanwhile,we analyzed 5-SNPs?rs115321619,rs73926263,rs73926264,rs73926265,rs55981512?haplotype from the 44 SNPs by 92populations?N=4986?.Finally,we developed multiplex system of 44 SNPs based on mini-sequencing.Then,191 individuals with self-declared ancestry information were typed and ancestry assignment performance was evaluated by analyzing statistics of LR,ancestry component and PCA.Results:Forty-four Tibetan ancestry informative SNPs were selected using F_ST values(F_ST>0.3)and?values??>0.4?.Tibetan population displayed a distinct cluster which was different from other populations in East Asian by STRUCTURE analysis.The PCA analysis showed that Tibetan population was separated from other populations in East Asian.Furthermore,the 5-SNPs haplotype displayed a special frequency distribution pattern between populations from Tibet and peripheral regions.The 44 SNPs multiplex system and algorithm were used to infer the ancestry of 191 individuals and the accuracy rate was>90%.Conclusion:Here we selected 44 ancestry informative SNPs of Tibetan population and developed a multiplex system.The system can be used to differentiate Tibetan population from other East Asian populations with an accuracy rate>90%.This panel can be used for forensic DNA ancestry inference.