单核苷酸多态性研究进展

单核甘酸多态性（ SNPs）是继 RFLP和微卫星多态性标记之后的新一代遗传标记系统,具有密度高、遗传稳定、分析易自动化等特点。 SNPs可通过电泳、 PCR、酶切及测序等方法检测,已广泛应用于基因作图、疾病相关性分析、群体遗传学及药物研究等领域。     

湖北地区德国牧羊犬10个微卫星DNA基因座遗传多态性研究

目的研究85头德国牧羊犬的10个基因座多态性。方法选用美国应用生物系统公司的10个商用犬微卫星基因座荧光标记复合扩增试剂盒进行PCR、并进行统计学分析。结果对85头德国牧羊犬的10个基因座的多态性研究表明,10个基因座累积DP值在0.9999972,非父排除率在0.9399,微卫星DNA基因座PEZ6、PEZ8、FHC2054的等位基因数均在8个以上,DP值接近或超过0.9,杂合度接近或超过0.7,能有效地应用犬的个体识别和亲权关系鉴定,其它7个基因座均未达到理想的个体识别和亲权鉴定使用条件。结论联合使用多个犬微卫星基因座,可以用于犬的个体识别和亲权鉴定。     

克隆牛的DNA鉴定

目的建立26个多态性STR标记,进行克隆牛的鉴定。方法采用荧光标记PCR引物,进行PCR扩增,应用GeneScan技术分析26个牛的微卫星基因座遗传多态性。结果26对荧光标记引物均能对上述样品很好地扩增出DNA产物,并得到清晰的条带。根据实验观察到的数据计算,体细胞克隆牛供体奶牛与克隆小奶牛的偶合率为3.31×10-15,认定它们为相同来源;在所检测的26个微卫星标记中,体细胞克隆牛供体奶牛、克隆小奶牛与克隆小奶牛代孕荷斯坦母亲的基因型在21个标记上不符合母子遗传关系,可以排除其亲子关系。结论有助于今后开展对珍稀动物或家畜被盗的案件鉴定工作。     

海南地区汉族人群15个STR基因座的遗传多态性

<正>短串联重复序列(short tandem repeat,STR),又称微卫星DNA或简单重复序列,其长度多态性来源于2~6 bp重复单位拷贝数的个体差异,是目前在法医物证鉴定中应用最广泛的长度多态性遗传标记[1]。本研究采用Amp F詛STRTM华夏TM荧光标记复合扩增体系对海南地区汉族人群的15个常染色体基因座(D8S1179、D21S11、D7S820、CSF1PO、D3S1358、D5S818、D13S317、     

X染色体遗传标记的研究应用进展

X染色体遗传标记在法医学中占有不可或缺的位置,因其独特的结构和遗传特征而被应用于复杂亲缘鉴定。目前应用于法医遗传学领域的有超过50个高度多态性X-STRs,筛选到高度多态性的X-SNPs和X-Indels的数量也在逐渐增加,且X染色体特异性遗传标记对复杂疾病的易感性也受到了临床工作者的重视。本文就X染色体遗传标记在法医学及临床医学上的研究和应用进行综述。     

中国内蒙古地区蒙古族群体13个SNPs遗传多态性

单核苷酸多态性（SNP）是一种具有高度稳定性的遗传学标记。在基因多态性研究、基因图谱构建、疾病诊断、预防和药物筛选中具有重要作用。本文采用荧光标记片段长度差异等位基因特异性复合扩增技术,对内蒙古地区242名无血缘关系蒙古族个体13个SNP进行调查,并评价其法医学应用价值。     

广东为主汉族人群19个STR基因座遗传多态性

正STR遗传标记具有高度多态性,多个不连锁的STR遗传标记联合应用时具有高度识别力,近年来成为法医学DNA分析的首选工具~([1])。由于等位基因频率在不同地区人群中具有显著差异~([2-3]),在应用STR基因座进行个体识别和亲权鉴定时需要调查该地区人群的遗传多态性。本研究对中国13 939个无关汉族个体(以广东汉族为主)使用Goldeneye誖DNA身份鉴定系统20A     

基于DNA预测人类可见外表特征的综述

本文介绍了基于DNA预测人类可见外表特征的法医学动机及筛选预测性DNA标记的科学挑战,讨论了目前认为很有应用前景的研究结果,比如现在科学水平只能达到通过高度关联的DNA标记准确预测性别、红色头发颜色、蓝色和棕色虹膜颜色。同时也讨论了现在看来不太有前景的应用,比如成年人的身高、人类面部特征等,为我国法医工作者今后进行相关研究提供一些参考。     

试论我国技术侦查立法的完善

技术侦查在现代各国侦查实践中被普遍应用,但技术侦查因其高度的秘密性、强制性对特点容易造成对公民权利的侵犯.我国立法对技术侦查缺乏明确而详尽的规定,刑诉法修正案虽对技术侦查做了一些规定,却存在着许多不完善之处.我们应对其立法的不完善之处进行思考并加以修正,以建立完善的法律机制对其加以规范从而更好地发挥其积极作用.     

利用种属特异性SSR荧光引物检出稀释液中罂粟DNA1例

正基于DNA检测技术建立的罂粟种属鉴别系统,能准确识别幼苗期罂粟、罂粟植株残渣、罂粟壳和罂粟种子,但针对涉毒案件中稀释液体所含罂粟的DNA种属检验目前尚无报道~([1-2])。本文应用种属特异性SSR荧光引物(simple sequence repeat,微卫星标记)的DNA检测技术,通过提取、扩增方法的优化,从1例涉毒案件送检的罂粟稀释浆液样本中检出SSR谱带并成功破案,为将来涉毒案件中类     

4个STR基因座在广东汉族人群的单倍型分布

调查DYS19、DYS390和DYS389Ⅰ/Ⅱ基因座在广东汉族群体的单倍型分布。PCR扩增后,用不连续PAGE电泳系统分型。在130名无关男性个体中,共检出81种不同的单倍型,其中52种只出现过1次。4个基因座单倍型的遗传多样性、个体识别率和非父排除率分别为0.9989,0.9824,0.9824,结果表明,4个STR基因座的单倍型检测在法医学个体识别和亲权鉴定方面有较高的应用价值。     

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。     

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。     

Analysis of global variability in 15 established and 5 new European Standard Set (ESS) STRs using the CEPH human genome diversity panel

The CEPH human genome diversity cell line panel (CEPH-HGDP) of 51 globally distributed populations was used to analyze patterns of variability in 20 core human identification STRs. The markers typed comprised the 15 STRs of Identifiler, one of the most widely used forensic STR multiplexes, plus five recently introduced European Standard Set (ESS) STRs: D1S1656, D2S441, D10S1248, D12S391 and D22S1045. From the genotypes obtained for the ESS STRs we identified rare, intermediate or off-ladder alleles that had not been previously reported for these loci. Examples of novel ESS STR alleles found were characterized by sequence analysis. This revealed extensive repeat structure variation in three ESS STRs, with D12S391 showing particularly high variability for tandem runs of AGAT and AGAC repeat units. The global geographic distribution of the CEPH panel samples gave an opportunity to study in detail the extent of substructure shown by the 20 STRs amongst populations and between their parent population groups. An assessment was made of the forensic informativeness of the new ESS STRs compared to the loci they will replace: CSF1PO, D5S818, D7S820, D13S317 and TPOX, with results showing a clear enhancement of discrimination power using multiplexes that genotype the new ESS loci. We also measured the ability of Identifiler and ESS STRs to infer the ancestry of the CEPH-HGDP samples and demonstrate that forensic STRs in large multiplexes have the potential to differentiate the major population groups but only with sufficient reliability when used with other ancestry-informative markers such as single nucleotide polymorphisms. Finally we checked for possible association by linkage between the two ESS multiplex STRs closely positioned on chromosome-12: vWA and D12S391 by examining paired genotypes from the complete CEPH data set.     

Population genetics of HPRTB, F13B, and LPL in Pernambuco, Northeast Brazil

One hundred thirty-four unrelated Northeast Brazilian individuals were typed for the HPRTB, F13B, and LPL short tandem repeats (STRs). DNA was amplified by specific primers and identified by silver staining of polyacrylamide gels. The allelic frequencies of these loci were in agreement with Hardy-Weinberg proportions. The most frequent alleles were HPRTB*13, F13B*10, LPL*10. The combined probability of paternity and the discrimination power of these 3 STRs were high, permitting their utilization for forensic science purposes.     

Population data of new Y-chromosome STRs GATA C4, DYS438, DYS437, GATA A7.2, GATA H4, DYS439 and GATA A10 in males from Colombia

Two hundred twenty-five unrelated males were typed for 7 over 8 loci Y-chromosome STRs proposed in a collaborative study by The Spanish and Portuguese ISFG Working Group. The markers amplification were in two multiplex reactions GEPY I with GATA C4, DYS438, DYS437, DYS461 (GATA A7.2) and GEPY II with GATA H4, DYS439, GATA A10 and DYS460 (GATA A7.1). All gene diversities were upper 0.5 with the highest value in DYS439 with 0.64. Furthermore, 152 haplotypes from 7 loci Y-chromosome STRs were found within studied population and a high haplotype diversity 0.9902 was found. The DYS460 (GATA A7.1) marker can not be studied because its diverse alleles were not able for interpret.     

Genetic variation of 23 STR loci in a Northeast Colombian population (department of Santander)

The most efficient markers to solve filiation cases are the STRs, including complex cases that require the analysis of a greater number of markers. In this study samples from 123 unrelated individuals from the department of Santander (northeast Colombia) were typed for 23 autosomal STRs included in VeriFiler express kit (Thermo Fisher Scientific),and their allele frequencies and parameters of forensic relevance were determined. Results demonstrate independence within and between the loci analyzed, and the accumulate power of exclusion for the full set of markers was high (99.9996%), as well as the match probability, which was 1 in 8.77E + 29. Therefore, this northeast Colombian population database can be used in forensic to estimate the frequency of the genetic profile using of a multiple locus including in this DNA kit.     

Y-chromosome STR-haplotype typing in El Salvador

Eight Y-chromosome STRs were investigated in a male population sample from El Salvador. Complete Y-chromosomal STRs haplotypes were obtained in 121 individuals, among which 107 different haplotypes were observed. The two most common haplotypes were shared by approximately 4% of the sample, while 100 haplotypes were unique. The gene diversity was 0.9883 and the discrimination capacity was 0.8926. The combined Y-chromosome STR polymorphisms provide a powerful discrimination tool for routine forensic applications.     

Pros and cons in the use of SNPs in forensic kinship investigation: a comparative analysis with STRs

Recent advances in single nucleotide polymorphisms (SNPs) research have raised the possibility that these markers could replace the forensically established short tandem repeats (STRs). In this work, we compare STRs and SNPs applicability for kinship investigation in terms of expected informative content and probability of occurrence of "difficult cases" (when isolated Mendelian incompatibilities between alleged father and child are found). Since SNPs have a much lower mutation rate than STRs, these difficulties were expected to occur less frequently if SNPs were used instead of STRs. The purpose of this paper is to make some simulations allowing the estimation of how often such difficult cases are expected to occur using both types of markers and how serious can be their impact in routine work. Our results demonstrate that a battery based exclusively on SNPs matching the informative power of current STR kits would be prone, if applied to routine paternity investigation, to the occurrence of cases where the statistical evidence would be inconclusive. We infer that the introduction of a SNP based strategy, as a substitute to the now classical STR approach poses statistical problems that must be carefully evaluated.     

河南汉族人群27个Y-STR基因座遗传多态性

目的 调查27个Y-STR基因座在河南汉族男性人群中的遗传多态性.方法 应用Yfiler（R） Plus试剂盒,对河南地区1100名汉族男性无关个体血样进行PCR扩增,3500XL型遗传分析仪电泳检测,GeneMapper-ID-X软件进行等位基因分型.结果 1100名男性共检出1098种不同的单倍型,其中1094种为单一型,另有3种单倍型均检出2例,HD（单倍型）值为0.999995;27个Y-STR基因座的GD值为0.3833～0.9663.结论 27个Y-STR基因座多数在河南汉族男性人群中有较好分布,对法医学应用和人类群体遗传学研究具有重要价值.