ALLELE DISTRIBUTION OF FIVE X-CHROMOSOME SHORT TANDEM REPEAT LOCI IN EWENKE POPULATION OF NORTH CHINA

Objective To study the allele genetic polymorphism of five short tandem repeat （STR） loci on X-chromosome in Ewenke population of north China and to provide basic data for forensic identification. Methods Genomic DNA was extracted from EDTA-whole blood of Ewenke population by Chelex-100. The DNA samples were amplified by PCR and were analyzed by polyacrylamide gel electrophoresis and silver staining. The sequence length variations of DXS6799, DXS8378, DXS101, HPRTB, and DXS6789 loci on X-chromosome in 98 unrelated Ewenke individuals were investigated. Results All five loci analyzed showed high polymorphism and genetic stability. The data of the five X-chromosome STR loci in Ewenke ethnic group of China was in accordance with Hardy-Weinberg equilibrium by Chi-square test. Conchusion Allele polymorphism of five X-chromosome STR loci can be used as a genetic marker for forensic identification and population genetic research.

Utilizing Short Tandem Repeats (STRs) as a Resolving Matrix in Parental Dispute DNA Analysis

Interest in DNA analysis using short tandem repeats (STR) as finger printing tools in forensic medicine has gained tremendous application, as expression of these nuclear factors have enhanced forensic examination. Here we used this Biochemical characterization after conventional extraction process, polymerase chain reaction (PCR), gel electrophoresiss and a sequencer to distinguish and resolve parental dispute. The differential migration of labeled DNA fragments which attains excitation energy with a laser elicits fluorescent light of different wavelength depending on the dye used. A data collection software (Genemapper) collects raw data (spectrograph) and converts it to an electropherogram that is interpreted. By comparing the DNA profiles, inclusion and exclusion criteria were elucidated to resolve disputes. The inherent discriminating power of STRs used in analysis enhances resolution of cell mixtures, genetic aberration, substantiation of tissue origin and provides genetic distinction which is a robust and reliable approach in resolving parental disputes.

A NORTHWEST DATABASE MODEL OF SHORT TANDEM REPEAT LOCI IN FORENSIC MEDICINE

Objective To establish the northwest database of short tandem repeat(STR) loci in forensic medicine. Methods Bloodstains or whole blood samples were collected from the unrelated prisoners in Xi'an city. Genetic distribution for 13 STR loci and amelogenin locus were determined in prisons based on GeneScan. One primer for each locus was labeled with the fluorescent by 5 FAM, JOE, or NED. The forensic database were generated by using multiple amplification, GeneScan, genotype, and genetic distribution analysis. Results 113 alleles and 302 genotypes were observed, with the corresponding frequency between 0.0050-0.5250 and 0.0100-0.4100. The mean H was 0.7667. The accumulative DP was 0.9999999,. The accumulative EPP was 0.9999999. The scope of PIC was 0.6036- 0.8562 . PM was less than 10 -11 . The observed and expected genotype frequencies were evaluated using χ 2 test and all were in accordance with Hardy Weinberg equilibrium ( P > 0.05 ). Conclusion STR loci is an ideal genetic marker with powerful polymorphism and stable heredity. It can be used for individual identification and paternity in forensic medicine. The forensic DNA database model can be established successfully.

Identification and characterization of short tandem repeats in the Tibetan macaque genome based on resequencing data

The Tibetan macaque, which is endemic to China, is currently listed as a Near Endangered primate species by the International Union for Conservation of Nature （IUCN）（2017）. Short tandem repeats （STRs） refer to repetitive elements of genome sequence that range in length from 1-6 bp. They are found in many organisms and are widely applied in population genetic studies. To clarify the distribution characteristics of genome-wide STRs and understand their variation among Tibetan macaques, we conducted a genome-wide survey of STRs with next-generation sequencing of five macaque samples. A total of 1 077 790 perfect STRs were mined from our assembly, with an N50 of 4 966 bp. Mono-nucleotide repeats were the most abundant, followed by tetra- and di-nucleotide repeats. Analysis of GC content and repeats showed consistent results with other macaques. Furthermore, using STR analysis software （IobSTR）, we found that the proportion of base pair deletions in the STRs was greater than that of insertions in the five Tibetan macaque individuals （P〈0.05, t-test）. We also found a greater number of homozygous STRs than heterozygous STRs （P〈0.05, t-test）, with the Emei and Jianyang Tibetan macaques showing more heterozygous loci than Huangshan Tibetan macaques. The proportion of insertions and mean variation of alleles in the Emei and Jianyang individuals were slightly higher than those in the Huangshan individuals, thus revealing differences in STR allele size between the two populations The polymorphic STR loci identified based on the reference genome showed good amplification efficiency and could be used to study population genetics in Tibetan macaques. The neighbor-joining tree classified the five macaques into two different branches according to their geographical origin, indicating high genetic differentiation between the Huangshan and Sichuan populations. We elucidated the distribution characteristics of STRs in the Tibetan macaque genome and provided an effective method for screening polymorphic STRs. Our results also lay a foundation for future genetic variation studies of macaques.

Mapping short tandem repeats for liver gene expression traits helps prioritize potential causal variants for complex traits in pigs

Background:Short tandem repeats(STRs)were recently found to have significant impacts on gene expression and diseases in humans,but their roles on gene expression and complex traits in pigs remain unexplored.This study investigates the effects of STRs on gene expression in liver tissues based on the whole-genome sequences and RNA-Seq data of a discovery cohort of 260 F6 individuals and a validation population of 296 F7 individuals from a heterogeneous population generated from crosses among eight pig breeds.Results:We identified 5203 and 5868 significantly expression STRs(eSTRs,FDR<1%)in the F6 and F7 populations,respectively,most of which could be reciprocally validated(π1=0.92).The eSTRs explained 27.5%of the cisheritability of gene expression traits on average.We further identified 235 and 298 fine-mapped STRs through the Bayesian fine-mapping approach in the F6 and F7 pigs,respectively,which were significantly enriched in intron,ATAC peak,compartment A and H3K4me3 regions.We identified 20 fine-mapped STRs located in 100 kb windows upstream and downstream of published complex trait-associated SNPs,which colocalized with epigenetic markers such as H3K27ac and ATAC peaks.These included eSTR of the CLPB,PGLS,PSMD6 and DHDH genes,which are linked with genome-wide association study(GWAS)SNPs for blood-related traits,leg conformation,growth-related traits,and meat quality traits,respectively.Conclusions:This study provides insights into the effects of STRs on gene expression traits.The identified eSTRs are valuable resources for prioritizing causal STRs for complex traits in pigs.

Application of Short Tandem Repeat in Prenatal Diagnosis for Phenmylketonuria during the First Trimester

Objective : To find a simple and rapid way far the prenatal diagnosis of phenyUce-tonuria (PKU) during the first trimester in order to prevent inborn PKU patients as early as possible. Methods :DNA was extracted respectively from the Mood sampleps of 9 families' members and chori-onic tissues of 9 embryoes by cliorionic vittus sampling (CVS). The independent short tandem repeat (STR) alleles of members in 9 families with classic form of PKU were analyzed and prenatal diagnosis were conducted using polymerase chain reaction (PCR) together with denaturing gradient gel elec-trophoresis(DGGE)and silver dyeing. Results-.We identified 1 embryo with PKU, 2 normal individuals and 5 carriers among 9 subjects. Conclusion: Prenatal diagnosis for PKU by STR is available in the first trimester. This procedure was promising and would be widely used in Chinese population.

Genetic and structural characterization of 20 autosomal short tandem repeats in the Chinese Qinghai Han population and its genetic relationships and interpopulation differentiations with other reference populations

China is a multinational country composed of 56 ethnic groups of which the Han Chinese accounts for 91.60%.Qinghai Province is located in the northeastern part of the Qinghai-Tibet Plateau,has an area of 72.12 km2,and is the fourth largest province in China.In the present study,we investigated the genetic polymorphisms of 20 short tandem repeat (STR) loci in a Qinghai Han population,as well as its genetic relationships with other populations.A total of 273 alleles were identified in 2 000 individuals at 20 loci,and the allelic frequency ranged from 0.0002 to 0.5327.The 20 STR loci showed a relatively high polymorphic rate in the studied group.Observed and expected heterozygosities ranged 0.613 0-0.907 5 and 0.614 8-0.920 0,respectively.The combined power of discrimination,and the probability of exclusion in duo and trio cases were 0.999 999 999 999 999 999 999 999 34,0.9999960 and 0.9999999965,respectively.Analyses of interpopulation differentiation revealed that the most significant differences were found between the Qinghai Han and Malaysian,while no significant differences were found between the Qinghai Han and Han people from Shaanxi and Jiangsu.The results of principal component analysis,multidimensional scaling analysis and phylogenetic reconstructions also suggested the close relationships between the Qinghai Han and other two Han populations.The present results,therefore,indicated that these 20 STR loci could be used for paternity testing and individual identification in forensic applications,and may also provide information for the studies of genetic relationships between Qinghai Han and other groups.

Mutation Studies of 31 Highly Mutated Y-chromosomal Short Tandem Repeat Systems in the Han Population of Northern China

A six-color fluorescent multiplex amplification system for 31 Y-chromosomal short tandem repeats(Y-STRs)(DYS19,DYS390,DYS391,DYF399S1,DYF404S1,DYS439,DYS444,DYS449,DYS452,DYS456,DYS458,DYS460,DYS481,DYS508,DYS513,DYS516,DYS518,DYS543,DYS547,DYS549,DYS552,DYS557,DYS570,DYS576,DYS612,DYS622,DYS626,DYS627,DYS630,DYS635,and Y-GATA-A10)was developed for investigating the mutation rates of 31 highly mutated Y-STR genes in the Han population of northern China.The mutation rates of the 31 highly mutated Y-STRs were calculated using the father-son pair study method after typing 526 Northern Han father-son pairs with this system.Statistically,148 Y-STR mutations were found,with mutation rates ranging from 0(95%confidence interval[CI]0 to 9.0×10^(−3),DYS622)to 7.0×10^(−2)(95%CI 5.1×10^(−2)to 9.7×10^(−2),DYF399S1).Out of these,126 father-son pairs were successfully identified,with a distinction rate of 24.0%(95%CI 20.4%-27.9%).The ability of the 31 highly mutated Y-STRs to distinguish closely related males from the same paternal lineage in the Northern Han population is extremely valuable for criminal investigations and other purposes.

Genetic Polymorphisms of 22 Novel Autosomal Short Tandem Repeat Loci in Sierra Leone Population

Background:Exploring and identifying novel alleles of noncombined DNAIndex System(CODIS)short tandem repeat(STR)loci in different ethnic groups is important for the establishment of forensic reference databases and study of population genetics.Aim:This study is aimed to explore the genetic polymorphism of 22 non-CODIS autosomal STR loci(D6S477,D18S535,D19S253,D15S659,D11S2368,D20S470,D1S1656,D22-GATA198B05,D8S1132,D4S2366,D21S1270,D13S325,D9S925,D3S3045,D14S608,D10S1435,D12S391,D7S3048,D17S1290,D5S2500,D2S1338,and D16S539)in Sierra Leone population and analyze the population genetic relationships in comparison with otherpopulations.Materialsand ethods:The amples of a total of 495 unrelated individuals(274 females and 221 males)from Sierra Leonewere examined by the Microreader^(TM)23SPID System,and their genetic polymorphisms and associated forensic parameters were calculated.The genetic relationships between Sierra Leonepopulation and other populations were evaluated as well.Results:Atotal of 287 alleles were observed with allelic frequencies ranging from 0.001 to 0.399.The cumulative power of discrimination(CPD)of the 22 autosomal STR loci was 0.99999999999999999999999999999538.The cumulative probability of exclusion(CPE)of the 22 autosomal STR loci was 0.9999998514(CPEdous)and 0.9999999999826(CPEtrios).All of the STR loci reached the Hardy–Weinberg equilibrium after Bonferroni correction.The population genetics analysis results demonstrated that Sierra Leone population exhibited distinctive genetic characteristics compared to those of East Asian populations and it had relatively close genetic distances to the Uygur population.Conclusion:The results of this study could enrich the forensic databases with Sierra Leone population.The 22 STR loci are highly polymorphic and could be used for forensic practice and population genetics studies.

贵州汉族人群21个非CODIS STR基因座的遗传多态性分析

目的调查贵州汉族人群21个非DNA检索系统(CODIS)的短串联重复序列(STR)基因座的遗传多态性,并评估其在法医学上的应用价值。方法选取301例贵州汉族无关个体血样,采用AGCU21+1荧光标记复合扩增系统对样本进行聚合酶链式反应(PCR),3500型全自动遗传分析仪对PCR扩增产物进行电泳分离,Gene Mapper ID-X 1.3软件进行STR基因分型,Modified-Powerstates软件包获得各基因座的等位基因频率、杂合度(H)、匹配概率(PM)、个体识别率(DP)、非父排除率(PE)、多态信息含量(PIC)、累积个体识别能力(TDP)、累积非父排除率(CPE)及各基因座的Hardy-Weinberg平衡检验,采用Genepop软件对两两基因座进行连锁不平衡分析;同时选择已报道的7个地区汉族人群作为参考,对8个汉族人群基因频率进行主成分分析(PCA),应用MEGA 7.0软件通过Neighbor-Joining(N-J)法构建8个地区汉族人群的系统发育树。结果 21个STR基因座共检测出了157个等位基因,436种基因型,基因频率介于0.001 7~0.584 7,PM介于0.052 6(D19S433)~0.226 8(D1S1627),DP介于0.773 2(D1S1627)~0.947 4(D19S433),PE介于0.272 9(D1S1627)~0.586 7(D22S1045),PIC介于0.533 2(D1S1627)~0.803 0(D19S433);TDP为1-4.645 5×10-20,CPE为0.999 998 822;与已报道的7个汉族群体比较,贵州和湖南汉族人群遗传关系最近,与宁夏汉族份遗传关系最远。结论 21个非CODIS STR在贵州汉族人群具有较好的多态性及个体识别能力,可作为法医学亲权鉴定和个人识别的有效补充。

21个非CODIS STR基因座的遗传多态性

目的调查华东汉族人群21个非CODIS STR基因座的遗传多态性并评价其法医学应用价值。方法用AGCU 21+1 STR试剂盒,对华东地区汉族225个无关个体的21个非CODIS STR基因座进行扩增,用3130遗传分析仪检测扩增产物,GeneMapper ID v3.2软件进行分型,采用PowerStats v12.xls和Cervus 2.0分析软件计算常用法医遗传学参数。结果 21个非CODIS STR基因座的频率分布在本组人群中均符合Hardy-Weinberg平衡。杂合度分布为0.596～0.804,个体识别率为0.764～0.948,二联体非父排除率(PEduo)为0.176～0.492,三联体非父排除率(PEtrio)为0.334～0.663,多态信息含量(PIC)为0.522～0.807。二联体累积非父排除率(CPE)为0.999707,三联体CPE为0.9999994,累积个体识别率(CDP)为0.99999999999999999994。结论 21个非CODIS STR基因座具有良好的遗传多态性,能有效运用于个体识别和三联体亲子鉴定,也可作为二联体亲子鉴定案例的补充工具。

Comparison of STR polymorphism among a Kirgiz ethnic group from Sinkiang and other groups

Objective To study the genetic relationship between Kirgiz individuals living in Sinkiang China and analyze the difference among Kirgiz and the other population with STR polymorphisms.Methods PCR amplification was performed using PE9700,the PCR products were typed by automated sequencer and genescan.Results A database of nine STR loci of Kirgiz was established.It shows there are at least 73 STR alleles and 191 genotypes in Kirgiz.Genotype frequencies distribution showed no deviation from Hardy-Weinberg equilibrium by χ2-test.Kirgiz was compared with the other Chinese ethnic groups,then the American Black and the White.Conclusion These results suggested that the nine STR loci and Amelogenin locus were very useful in human identification,biological archaeology and gene resource studies.

Silver STR Ⅲ系统基因座中等位基因在葡萄胎基因组中的分布及其意义

目的研究S ilver STR(Ⅲ系统3个基因座中各等位基因在葡萄胎基因组中的分布及潜在意义。方法对应用多重PCR和变性聚丙烯酰胺凝胶电泳技术鉴别出的39例遗传物质完全来自父方的完全性葡萄胎进行分析,统计S ilverSTR(Ⅲ系统3个基因座中各等位基因的出现率。结果在39例葡萄胎中,S ilver STR(Ⅲ系统的D16S539座位出现6个等位基因,D7S820座位出现5个等位基因,D13S317座位出现7个等位基因;D16S539座位中等位基因14出现率显著高于人群(P<0.05),D7S820座位中等位基因9出现率显著低于人群(P<0.01),其余各等位基因出现率与人群基因频率无显著差异;D16S539、D7S820和D13S317基因座位杂合度分别为0.1795,0.1282和0.1538;其中可追踪的23例良性葡萄胎中,D16S539出现6个等位基因,D7S820出现4个等位基因,D13S317出现7个等位基因;可追踪的7例侵袭性葡萄胎中,D7S820出现5个等位基因,D16S539与D13S317均出现4个等位基因,其中D16S539和D13S317座位的等位基因9出现率高于良性葡萄胎(P<0.01和P<0.05)。结论葡萄胎D16S539、D7S820和D13S317基因座位等位基因杂合度远低于人群杂合度;葡萄胎具有侵袭性与D16S539和D13S317座位的等位基因9出现率具有相关性。

天津市汉族胎儿D21S1411和D21S1413 STR基因座遗传多态性的研究

目的:调查天津市汉族胎儿21号染色体上D21S1411和D21S1413短串联重复序列(STR)的遗传多态性,获取群体遗传学数据,为其应用于产前诊断提供依据。方法:选取211例产前诊断样本,提取DNA,复合扩增D21S1411和D21S1413 STR基因座,非变性聚丙烯酰胺凝胶电泳,分析扩增产物。用PowerState V12软件分析群体遗传学指标。结果:D21S1411 STR基因座共发现9种等位基因,45种基因型。D21S1413 STR基因座共发现7种等位基因,28种基因型。D21S1411基因座的观察杂合度(Ho)、多态信息含量(PIC)、个体识别率(DP)和非父排除率(PE)分别为75.4%、0.85%、0.967%、0.516%。D21S1413基因座的Ho、PIC、DP、PE分别为87.2%、0.82%、0.947%、0.739%。D21S1411和D21S1413 2个STR基因座累计PIC为0.973,累计DP为0.998,累计PE为0.874。结论:D21S1411和D21S1413 STR基因座均符合Hardy-W e inberg平衡定律,在天津市汉族胎儿群体中具有较高的杂合度和多态信息含量,可用于唐氏综合征的基因诊断和产前基因诊断。

GENETIC POLYMORPHISM OF SIX Y CHROMOSOMAL STR IN CHINESE HUI ETHNIC GROUP

Objective To study genetic polymorphism of 6 Y chromosomal STR in Hui ethnic group living in Ningxia Hui ethnic autonomous region, in order to evaluate their usefulness in forensic science and enrich the Chinese genetic information resources. Methods We investigated 101 unrelated, healthy, male individuals of Hui ethnic group and studied their allelic frequency distribution and haplotype diversity of 6 Y chromosomal STR. Primer for each loci was labeled with the fluorescent by FAM (blue) or TAMRA(yellow). The data of Hui ethnic group were generated co-amplification, GeneScan, genotype, and genetic distribution analysis. Results 31 alleles and 43 phenotype(DYS385) were detected, with the frequencies ranging from 0.0099-0.7129. Out of a total of 101 individuals, 96 showed different haplotypes; 91 were unique; 5 were found 2 times. The haplotype diversity for 6 Y-STR loci was 0.9990. Conclusion The date obtained can be valuable for individual identification, paternity testing in forensic fields and for population genetics because of 6 Y-STR loci high polymorphism.

ANALYSIS ON GENETIC POLYMORPHISM OF 6 STR LOCI ON CHROMOSOME 12 IN CHINESE HAN POPULATION

Objective To analyze the genetic polymorphism of 6 STR loci (D12S358, D12S1675, D12S1663, D12S1697, D12S1725 and D12S1613) on chromosome 12 in Chinese Han population. Methods EDTA-blood specimens were collected from 153 unrelated individuals of Chinese Han population in Shaanxi province. Allele and genotype frequencies for the 6 STR loci were estimated and statistical parameters of polymorphism were calculated. Results 8 alleles and 18 genotypes, 10 alleles and 17 genotypes, 9 alleles and 15 genotypes, 12alleles and 29 genotypes, 12 alleles and 31 genotypes, 8 alleles and 11 genotypes were observed at D12S358, D12S1675, D12S1663, D12S1697, D12S1725 and D12S1613, respectively. No deviations of the observed allele frequency from Hardy-weinberg equilibrium expectations were found for any of these loci. The Heterozygotes of these 6 loci were 78.89%, 66.10%, 54.95%, 79.10%, 71.98% and 59.48%, respectively. It indicated the high genetic polymorphism of the loci in Chinese Han population. Conclusion The 6 STR loci belonged to the genetic marker system of high discriminutesation and high information in Chinese Han population and can be used in the study of gene-related diseases.

The development and application of a multiplex short tandem repeat(STR)system for identifying subspecies,individuals and sex in tigers

Poaching and trans-boundary trafficking of tigers and body parts are threatening the world’s last remaining wild tigers.Development of an efficient molecular genetic assay for tracing the origins of confiscated specimens will assist in law enforcement and wildlife forensics for this iconic flagship species.We developed a multiplex genotyping system“tigrisPlex”to simultaneously assess 22 short tandem repeat(STR,or microsatellite)loci and a gender-identifying SRY gene,all amplified in 4 reactions using as little as 1 ng of template DNA.With DNA samples used for between-run calibration,the system generates STR genotypes that are directly compatible with voucher tiger subspecies genetic profiles,hence making it possible to identify subspecies via bi-parentally inherited markers.We applied“tigrisPlex”to 12 confiscated specimens from Russia and identified 6 individuals(3 females and 3 males),each represented by duplicated samples and all designated as Amur tigers(Panthera tigris altaica)with high confidence.This STR multiplex system can serve as an effective and versatile approach for genetic profiling of both wild and captive tigers as well as confiscated tiger products,fulfilling various conservation needs for identifying the origins of tiger samples.