汉族12个STR位点群体遗传学调查

目的240个汉族无关个体12个STR位点基因频率调查及其法医学应用;方法采用12位点复合扩增及变性聚丙烯酰胺凝胶电泳基因分型;结果该系统12个STR基因位点在汉族人群中均为高识别率位点,特别适合于陈旧血痕检验;结论12位点STR-PCR复合扩增系统检测方法简便,经济实用,在法医个体识别和亲子鉴定中具有应用价值。     

67个X-SNP位点的分型检测和连锁不平衡检验

目的 筛选一组在中国汉族人群中具有法医学应用前景的X-SNP位点.方法 根据dbSNP和HapMap两个数据库提供的位点信息和频率数据从X染色体上筛选出67个候选X-SNP位点,采用多重PCR联合基质辅助激光解析电离飞行时间质谱技术检测中国汉族人群428名无关个体,获得67个候选X-SNP位点在中国汉族人群中的频率数据...     

Characterization of 26 miniSTR loci for improved analysis of degraded DNA samples

An additional 20 novel mini-short tandem repeat (miniSTR) loci have been developed and characterized beyond the six previously developed by our laboratory for a total of 26 non-CODIS miniSTR markers. These new markers produce short PCR products in the target range of 50-150 base pairs (bp) by moving the primer sequences as close as possible-often directly next to the identified repeat region. These candidate loci were initially screened based on their small amplicon sizes and locations on chromosomes currently unoccupied by the 13 CODIS STR loci or at least 50 Mb away from them on the same chromosome. They were sequenced and evaluated across more than 600 samples, and their population statistics were determined. The heterozygosities of the new loci were compared with those of the 13 CODIS loci and all were found to be comparable. Only five of the new loci had lower values than the CODIS loci; however, all of these were much smaller in size. This data suggests that these 26 miniSTR loci will serve as useful complements to the CODIS loci to aid in the forensic analysis of degraded DNA, as well as missing persons work and parentage testing with limited next-of-kin reference samples.     

Genetics and genomics of core short tandem repeat loci used in human identity testing

Over the past decade, the human identity testing community has settled on a set of core short tandem repeat (STR) loci that are widely used for DNA typing applications. A variety of commercial kits enable robust amplification of these core STR loci. A brief history is presented regarding the selection of core autosomal and Y-chromosomal STR markers. The physical location of each STR locus in the human genome is delineated and allele ranges and variants observed in human populations are summarized as are mutation rates observed from parentage testing. Internet resources for additional information on core STR loci are reviewed. Additional topics are also discussed, including potential linkage of STR loci to genetic disease-causing genes, probabilistic predictions of sample ethnicity, and desirable characteristics for additional STR loci that may be added in the future to the current core loci. These core STR loci, which form the basis for DNA databases worldwide, will continue to play an important role in forensic science for many years to come.     

单亲亲子鉴定的分析研究

目的从理论和实际应用方面客观评价13～15个STR位点应用于单亲亲子鉴定的准确性。方法依据中国人群基因频率资料,计算单亲亲子鉴定的非父排除率及单亲亲子鉴定的亲子关系概率,并选择有明确排除结论的104例排除案例,分析统计其中父-子二联体出现的排除指标数。结果对于单亲亲子鉴定,选用13～15个STR位点,联合非父排除率为0.9805～0.9906;亲子关系概率均大于99.73%。104例二联体排除案例中,有3例的排除指标数小于2,未发现排除指标为零的现象。结论若应用ProfilerPlus和CofilerPlus试剂盒的13个STR位点进行日常单亲亲子鉴定工作,存在微弱漏判非父的风险,必要时增加检测指标数。不排除案例的单亲亲子鉴定,其亲子概率均可达国际认定标准。     

江苏汉族人群30个插入/缺失位点的遗传多态性

目的调查30个插入/缺失(insertion/deletion,In Del)位点在江苏汉族人群中的遗传学信息,评估Investigator~ DIPplex试剂盒的使用价值,并用于指导江苏汉族人群的法医学分析。方法用Investigator~ DIPplex试剂盒对江苏地区305名汉族健康无关个体进行常染色体In Del位点的分型检测,统计分析30个In Del位点的频率数据及遗传学参数。结果 30个In Del位点在江苏汉族人群中的分布均符合Hardy-Weinberg平衡,有21个In Del位点的最小等位基因频率大于0.3。多态信息含量为0.089~0.375,个体识别率为0.093~0.500,二联体非父排除率为0.047~0.250,三联体非父排除率为0.046~0.219。30个In Del位点经连锁不平衡分析,各位点之间相互独立,累积个体识别率为1-7.369×10-8,二联体累积非父排除率为0.998 933 978,三联体累积非父排除率为0.997 806 392。除HLD118等5个位点外,群体间Fst值均小于0.06,在群体间差异较小。结论 Investigator~ DIPplex试剂盒中所含有的In Del位点可作为补充遗传标记应用于法医物证学相关检案工作。     

Portuguese population data on the six short tandem repeat loci — CSF1PO,TPOX, THO1, D3S1358, VWA and FGA

Allele frequencies for six tetrameric short tandem repeat (STR) loci CSF1PO, TPOX, THO1, D3S1358, VWA and FGA were determined in a Caucasian population sample from Portugal. All loci are highly polymorphic and meet Hardy-Weinberg expectations. There is little evidence for association of alleles among the six loci. The three loci D3S1358, VWA and FGA are more polymorphic and, hence, are more informative than the loci CSF1PO, TPOX, and THO1. However, all six loci would be useful for human identification applications. The STR allelic frequency data are similar to other Caucasian data.     

Retrospective study of the impact of miniSTRs on forensic DNA profiling of touch DNA samples

The theoretical advantages of miniSTRs are undeniable. Several studies show that miniSTRs are more sensitive and robust in the analysis of low template and degraded DNA. In this study we want to show the overall benefit of using miniSTRs in real forensic casework samples and show the percentage of samples that benefit from analysis with additional miniSTR loci in terms of resulting in a useful profile. The considered samples were 3064 touch DNA samples, analyzed in our accredited routine forensic DNA profiling laboratory between mid 2009 and mid 2013. Of these 3064 samples, 618 samples were analyzed using 13 loci, 532 samples using 15 loci and 1914 samples using 20 loci of which 5 were the mini- and midi-STR loci that were added to the extended European Standard Set (ESS). The retrospective results show a small increased success rate after implementation of extra loci and an even smaller increase after the implementation of the mini- and midi-STR analysis. The percentage of touch DNA samples that benefit from the analysis of additional mini- and midi-STR loci is limited.     

Genetic diversity in four tribal groups of western India: a survey of polymorphism in 15 STR loci and their application in human identification

Genetic diversity at 15 STR loci: 2 pentanucleotide and 13 tetranucleotide STR loci was determined in four highly endogamous tribal groups, viz. Madia-Gond, Mahadeo-Koli, Katkari and Pawara of western India. The distribution of genotypes at studied 15 loci was found in agreement with expected values according to Hardy-Weinberg equilibrium. The combined power of discrimination of 15 loci was calculated as 0.80 while combined power of exclusion was observed as 0.53 among the studied four tribal groups. The study demonstrate very low heterozygosity and low power of exclusion of the loci of Powerplex 16 among the selected groups indicating less informativeness of the studied markers in human identification testing.     

An STR forensic typing system for genetic individualization of domestic cat (Felis catus) samples

A forensic genotyping panel of 11 tetranucleotide STR loci from the domestic cat was characterized and evaluated for genetic individualization of cat tissues. We first examined 49 candidate STR loci and their frequency assessment in domestic cat populations. The STR loci (3-4 base pair repeat motifs), mapped in the cat genome relative to 579 coding loci and 255 STR loci, are well distributed across the 18 feline autosomes. All loci exhibit Mendelian inheritance in a multi-generation pedigree. Eleven loci that were unlinked and were highly heterozygous in cat breeds were selected for a forensic panel. Heterozygosity values obtained for the independent loci, ranged from 0.60-0.82, while the average cat breed heterozygosity obtained for the 11 locus panel was 0.71 (range of 0.57-0.83). A small sample set of outbred domestic cats displayed a heterozygosity of 0.86 for the 11 locus panel. The power of discrimination of the panel is moderate to high in the cat breeds examined, with an average P(m) of 3.7E-06. The panel shows good potential for genetic individualization within outbred domestic cats with a P(m) of 5.31E-08. A multiplex protocol, designed for the co-amplification of the 11 loci and a gender-identifying locus, is species specific and robust, generating a product profile with as little as 0.125 nanograms of genomic DNA.     

中国东部蒙古族人群15个STR基因座多态性研究

目的调查15个STR基因座在中国东部蒙古族人群中的基因频率分布。方法应用四色荧光标记引物复合扩增技术,对105名东部蒙古族无关个的血样15个STR基因座进行多态性研究。结果在东部蒙古族人群中15个STR基因座偶合率在0.0084～0.2169之间,个体识别概率(DP)在0.7831～0.9916之间,杂合度在0.5619～0.9231之间,三联非父排除率(PE)在0.4490～0.8444之间,多态性信息总量(PIC)在0.5438～0.9178之间,15个STR基因座总TDP值为0.9999999999998,所有基因座经χ2检验符合Hard-Weinberg平衡。结论上述15个STR基因座在东部蒙古族人群中等位基因分布较好,个体识别率高,适合法医个体识别和亲子鉴定。     

中国鄂温克族人群15个STR基因座多态性研究

目的调查15个STR基因座在中国鄂温克族人群中的基因频率分布。方法应用PowerPlex16System复合扩增系统,对99名鄂温克族无关个的血样DNA进行多态性研究。结果在鄂温克族人群中15个STR基因座偶合率(Pm)在0.0205～0.1733之间,个体识别概率(DP)在0.8267～0.9795之间,杂合度在0.6061～0.9091之间,三联非父排除率(PE)在0.4038～0.7690之间,多态性信息总量(PIC)在0.5985～0.8734之间,15个STR基因座总TDP值为0.9999999999998,所有基因座经χ2检验符合Hard-Weinberg平衡。结论上述15个STR基因座在鄂温克族人群中等位基因分布较好,个体识别率高,适合法医个体识别和亲子鉴定。     

Zimbabwe black population data on the six short tandem repeat loci – CSF1PO, TPOX, THO1, D3S1358, VWA and FGA

Allele frequencies for six tetrameric short tandem repeat (STR) loci CSF1PO, TPOX, THO1, D3S1358, VWA, and FGA were determined in a Black African sample population from Zimbabwe. All loci are highly polymorphic and meet Hardy-Weinberg expectations. An inter-class correlation test analysis detected only one departure from independence out of 15 pair-wise comparisons of the six loci (i.e., CSF1PO/VWA loci, P=0.026). The allele frequency data at four of the six STR loci in the Black African sample population are similar to African American data.     

Y-STR基因座应用于刑事案件的独特作用

目的探讨Y-STR基因座在刑事案件中的应用价值。方法采用Y-STR荧光标记复合扩增技术,结合案例应用。结果Y-STR基因座对于涉及男女混合、多名男性混合样本、性别鉴定、父权鉴定等案例中具有特有应用价值。结论Y-STR基因座可应用于法庭科学中的个体识别与同一认定,但在应用中要注意各种特例的发生。     

线粒体DNA nt8584、nt8701单核苷酸多态性研究

目的建立一种快速、准确的线粒体DNA单核苷酸多态性位点检测方法。方法收集62份无关个体血液样本,应用荧光定量PCR技术研究线粒体DNA nt8584、nt8701位点在中国汉族人群中的多态性。结果 nt8584位点检测到10例nt8584A、52例nt8584G,nt8584A/G变异频率为16∶84;nt8701位点检测到27例nt8701A、35例nt8701G,nt8701A/G变异频率为44∶56。结论所建立的荧光定量PCR方法分型准确、耗时短,适用于法医DNA检验。     

二联体亲权鉴定风险分析

目的探讨二联体亲权鉴定时存在的风险。方法选取22组经Goldeneye~(TM) 20A试剂盒检测后只有一个或没有不符合基因座的无关个体对构建假想家系。对其增加检测STRtyper-10G和/或AGCU 21+1 STR系统直至所有组不符合基因座个数大于3个,累积父权指数(CPI)不大于0.000 1。以三种规则:(1)不符合基因座数大于3个;(2)CPI值小于0.000 1;(3)同时满足(1)和(2),作为排除依据,使用不同数量的基因座(19个、26个、39个和46个)进行检测,讨论无关个体对的排除情况是否存在差异。结果 22组无关个体对,使用19个基因座和39个基因座以上的检测系统达到排除结果的分别为0组和22组。结论二联体亲子鉴定,使用19个基因座进行检测仍存在结果错判,39个基因座以上的检测系统能更有效的避免二联体的鉴定风险。     

单亲案的亲权概率的计算及认定标准

确定单亲案的亲权概率计算方法和认定标准。用多基因座DNA分析方法和计算多基因座累积平均非父排除率计算公式。检测8个以上的DNA多态性基因座,在等位基因的遗传不违反孟德尔规律的前提下,父权概率都可达到或超过0.9990的标准;对不存在亲生关系的案例,在用本方法时,都有3个或更多的基因座的等位基因遗传违反孟德尔规律。对单亲案的亲权鉴定,检测的多态性基因座要在8个以上。在肯定亲生关系时,父权概率要达到或超过0.9990;在否定亲生关系时,必须有3个以上或更多的基因座违反孟德尔遗传规律。     

广西壮、汉族人群F13A01、FESTPS、vWA三个STR基因座的遗传多态性

采用复合扩增、PAG电泳分离和银染检测技术,对广西壮、汉族人群的F13A01、FESFPS、vWA等3个STR基因座进行遗传多态性研究.3个基因座的基因型在广西壮、汉族人群的频率分布均符合Hardy-wein-berg平衡.3个STR基因座在广西壮族人群的个体识别力(DP)分别为0.8205、0.8566和0.9239;在广西汉族人群的个体识别力(DP)分别为0.8256、0.8455、0.9191.     

Genomic diversity at 15 fluorescent labeled short tandem repeat loci in few important populations of State of Uttar Pradesh,India

Genomic diversity at 15 short tandem repeat loci is studied in four major endogamous populations of Uttar Pradesh (UP), India. The studied populations included Thakur, Khatri, Kurmi and Jat; all of whom belong to Hindi speaking linguistic group of UP State of India. All the STR loci of Powerplex 16 System have been found highly significant in showing genomic diversity among the addressed populations. Homozygosity test values for all the 15 loci in studied population range between 0.053 and 0.999, following Hardy-Weinberg equilibrium. Distribution of allele pattern at fluorescent labeled 13 tetranucleotide repeat loci and two pentanucleotide repeat loci of Powerplex 16 System portrays that these markers are highly polymorphic, and thus, suitable in human identity testing and human genetic studies.     

4个miniSTR基因座复合扩增体系及应用

目的构建D6S474、D20S482、D4S2408、D6S1017等4个miniSTR基因座复合扩增体系,评价其对腐败检材的应用价值,调查4个基因座在汉族人群中的遗传多态性。方法采用不同荧光标记4个miniSTR基因座上游引物,构建复合扩增体系。用分子克隆方法制备等位基因分型标准物。采用上述体系对135份汉族无关个体血样进行检测,并计算群体遗传学参数。比较该体系与ID试剂盒在降解检材分析中的成功率。结果采用本文复合扩增体系检测,汉族人群中4个基因座基因型频率分布均符合Hardy-Weinberg平衡定律,累积个人识别能力为0.999 666,累积非父排除率为0.914 902。本文体系较ID试剂盒对自然腐败检材的分型成功率更高。结论 4个miniSTR基因座复合扩增体系对法庭科学实践,特别是对腐败检材的检测有应用价值。