Developing A Novel Panel Of Ancestry Informative Markers For Unknown DNA Donor Ancestry Estimates Of Intercont Inental Populations

Objective:To research and screen a panel of ancestry informative markers from autosomal used to distinguish between European, African and Asian populations,then based on the technology of SNa PshotTMand combined the related software for the description of genetic components of European, African and Asian populations and individual ancestry inference develop a multiplexed detection system for the unknown DNA donor population. The composite detection system should have the following features: 1. The SNPs are able to build compound detection system with highly information but little numbers; 2. A single pipe PCR(One- tube) is able to operate and reduce consumption of the DNA template; 3.The short fragments amplified(< 150 bp) which can be applicable to the analysis of the degradation of DNA template; 4. Using capillary electrophoresis detection is suitable for forensic genetics laboratory and enable the forensic DNA analysis to serve the criminal detection more effectively.Methods:Refered to the related literature and the information from the international databases,and based on the kinds of parameters of population genetics,we selected a set of SNPs for estimating ancestry original.Considering the domestic current situation of the existing large special equipment in the forensic DNA laboratory,the 27-plex SNPs composite amplification method was developed.First,We selected 27 AIMs from 908 AIMs screened of 52 genes associated with the phenotype based on the genotyping data of 1417 samplesas theory data of 11 populations from the Hap Map databases,and to verify its effectiveness1417 population samples were analyzed using this panel of AIMs analysis.Then based on the Micro sequencing technology of SNa PshotTM, we developed the Multiplexed assay,and1164 unrelated DNA samples from 17 populations of the world’s were collected for assay validation. Set up the population allele frequency databases of 27 locus allele frequency from 28 populations samples by analyzing results of statistics. Finally,we got population genetic components and individual genetic composition through the analysis of STRUCTURE and FI software,and made the individual ancestry inference together with the results of the random matching probabilities be the system for ancestry original inference.Meanwhile,validated the accuracy of genotyping and sensitivity etc.for the system.Results:We screened the 27 AIMs according to the following condition:which’s Hardy-Weinberg equilibrium(P>0.00001)are well balanced,the linkage disequilibrium is inexistent(r2<0.2)and the allele frequency distribution were highly contrasting among the different populations involved in this study(Fst>0.4). There are 10 East Asian AIMs(there are large δ values of East Asian/African and East Asian/European in the 10 SNPs) with a median Fst of 0.634(0.526-0.771), 9 European AIMs with a median Fst of 0.683(0.525-0.842), and 8 African AIMs with a median Fst of 0.811(0.772-0.883)in the 27 AIMs.The 27 locus were constructed based on The Sna PshotTMtechnology and formed the compound detection system, PCR amplification fragment length ranged from 89 bp to 149 bp.Using the SNPs panel we can successfully infer the ancestry inference of individuals with African, European, and East Asian ancestries. Furthermore, the system performed well when inferring the admixture of Eurasians(EUR:EAS) after analyzing admixed populations from Xinjiang(Central Asian): Tajik(68:27), Uyghur(49:46), kirgiz(40:57),and Kazak(36:60). For individual analysis, we interpreted each sample with a three-ancestry-component percentage and a population match probability sequence.We described the population STRUCTURE and the individual STRUCTURE with the pie charts. The ancestry component analyses for 2581 samples from 28 populations are consistent with the known origin, and the original ancestry inference can be obtained accurately,with the results of the random matching probabilities. This panel of AIMs was configured with significant and balanced discriminatory ability among African, European,and East Asian ancestries. The compound detection system has a highly accuracy, the consistency between genotyping results of SNa PshotTMand the sequencing results is 100%.Moreover,it has a highly sensitivity and the lowest concentration that produced a complete SNPs profile was 0.1 ng/μl.Conclusion:The established panel screened and developed by the 27 AIMs can be applied to analyze the genetic components of Asian,European,African and have a better ability for the admixed populations(European:African)and individual genetic composition.Based on SNa PshotTMtechnology the composite detection system have the high sensitivity, high accuracy, high flux, high efficient and economical advantages,which can be widely used in forensic DNA testing for unknown DNA donor ancestry estimates of intercontinental populations.