Analysis of the D1S80 (pMCT118) VNTR locus polymorphism in a native Kuwaiti population by the polymerase chain reaction

We have determined the allele and genotype frequencies at the hypervariable locus D1S80 in a native Kuwaiti population using the polymerase chain reaction technique and subsequent high resolution gel electrophoresis. In a sample of 200 individuals, 21 alleles and 57 genotypes were detected. The alleles with 18 and 24 repeat units were most common with frequencies of 0.188 and 0.408 respectively. The distribution of the observed genotypes was in agreement with the Hardy-Weinberg equilibrium prediction. The observed heterozygosity for the population sample was 0.80 with the allelic diversity of 0.781 ± 0.029 and the power of discrimination was 0.94. The data obtained in this study are potentially useful for individual identification in forensic casework.     

Sex identification of forensic specimens by polymerase chain reaction (PCR): two alternative methods

Sex identification of forensic samples (bloodstains and decomposed tissue) by polymerase chain reaction (PCR) was investigated. Amplification of a segment of the amelogenin gene using a pair of primers revealed both Y- and X-specific bands at the same time. The gene has counterparts in both the X and Y chromosomes and a small deletion in the former made it possible to distinguish them. Analysis of the X-specific band is the most reliable method for sex identification. THe locus includes a single copy gene so a sample of 250 ng/tube of deoxyribonucleic acid (DNA) is required for identification. Amplification of part of the DYZ1 locus was attempted as an alternative method for analysis of infinitesimal amounts of sample. Even DNA from putrefied tissue could be analyzed by PCR because the locus consists of thousands of copies of repeating units pHY10.     

用反相杂交技术对HLA-DQA1基因分型及其应用

目的 :HLA -DQA1其因的分型研究及在实际办案中的应用。方法 :PCR结合反相杂交检测技术对HLA -DQA1基因进行分型。结果 :检见7种基因 ,24种基因型 ,获得上海地区HLA -DQA1基因的基因频率及基因型的频率分布数据。结论 :对法医学中常见的血液 (痕 )、牙齿、精斑、混合斑、人体组织等检材进行HLA -DQA1分型检测 ,其结果稳定可靠 ,为实际办案提供了科学依据     

Discrimination between human and animal DNA: application of a duplex polymerase chain reaction to forensic identification

Identification of a report's species is one of the basic analyses in forensic laboratories. The authors report the case of 6 bone fragments recovered in a wooded area, which were not attributable to 1 animal species on the basis of morphologic examination. The aim of this study was to develop a duplex polymerase chain reaction (PCR) to discriminate human and animal origin of bone fragments. The method is based on the PCR amplification of cytochrome b and a 16S ribosomal mitochondrial DNA fragment, which has never been tested up to now. Our protocol combines a single-round PCR with direct visualization of amplicons in agarose gel, without sequencing analysis of the PCR products. The presence of a single band (359 bp) indicates a nonhuman origin of the sample, whereas 2 bands (157 and 359 bp) indicate a human biologic sample.This method revealed to be useful for forensic purposes because the 16S ribosomal mitochondrial DNA is a small human-specific fragment that is easily amplifiable even with degraded DNA from biologic materials such as old bones.     

Allele frequency distributions of four variable number tandem repeat (VNTR) loci in the London area.

Allele frequency distributions of four hypervariable minisatellite loci were obtained from a large sample of individuals in the London area. The sample is subdivided into three major ethnic groups; Caucasian, Afro-Caribbean and Asian, and histograms for these groups are displayed for comparison. The distributions are discussed in relation to mutation rates, heterozygosity and the computer analysis and processing of results.     

HLA-DQA1 typing in Danes by two polymerase chain reaction (PCR) based methods

A total of 280 persons were HLA-DQA1 typed by two different polymerase chain reaction (PCR) based methods: (i) a reverse dot-blot (RDB) method, which can differentiate between six alleles, and (ii) a combined PCR-restriction fragment length polymorphism (PCR-RFLP) and allele-specific amplification (ASA) method, which together recognise eight alleles. In 146 unrelated Danish individuals, the HLA-DQA1 alleles were in Hardy-Weinberg equilibrium. For identity testing, the power of discrimination (PD) of HLA-DQA1 was 0.932 with the RDB method and 0.942 with the PCR-RFLP/ASA method. For paternity testing, the theoretical chance of exclusion in HLA-DQA1 of non-fathers was 0.634 with the RDB method and 0.660 with the PCR-RFLP/ASA method.     

D3S1358等7个DNA位点的荧光法在法医学中的应用

报道了D3S1358、D16S539等7个DNA位点的复合扩增和四色荧光分析技术。经310自动测序仪检测7个位点 ,实现了STR位点同步扩增和自动检测目的。同一性实验表明 ,同一个体肌肉、血液、唾液和头发等组织STR位点基因型完全一致。对2个四代家系、3个三代家系的调查结果表明 ,这些位点符合孟德尔遗传定律。D3S1358、D16S539等7个位点对陈旧、微量的检材适用性很强,灵敏度达75pg ,在法医个人识别和亲子鉴定中有着重要意义     

Y-chromosomal short tandem repeats haplotyping from vaginal swabs using a chelating resin-based DNA extraction method and a dual-round polymerase chain reaction

Reported are 2 autopsy cases in which Y-chromosomal microsatellite short tandem repeats DYS19, DYS389I and II, DYS390, and DYS393 could be haplotyped with vaginal swabs by using a Chelex 100-based DNA extraction method and dual-round polymerase chain reaction. The extraction of DNA from vaginal swabs by using this method was as efficient or more efficient than using proteinase K and phenol-chloroform extraction or the alkaline lysis methods. Y-chromosomal microsatellite short tandem repeats haplotyping based on the dual-round polymerase chain reaction method provided genotypes from all the loci determined. Although amplification of Y-chromosomal microsatellite short tandem repeats loci is not directly involved in the existence of spermatozoa, it is considerably advantageous for male individualization from body fluid mixture stains in criminal cases.     

中国法医学家--吴梅筠教授

吴梅筠教授,1926年生于浙江省黄岩市.1952年上海第一医学院医学系毕业.1953年7月参加卫生部主办的法医学高级师资培训班结业后被分配至原四川医学院.吴梅筠教授与吴家馼教授一起正式开创了法医学教学、科研和检验工作.1983年建立法医学教研室,任教研室主任.1986年成立法医学系,任法医物证教研室主任,是华西医科大学法医学系和四川省法医学会的创始人之一.1980 1982年赴美国,进修免疫血液学.1984年6月12月赴澳大利亚合作进行计划生育科研.1985年1月作为国家教委组织的法医学教育考察团成员兼翻译赴美国考察.1990、1991年曾两次赴日本参加第一届国际法科学进展学术会议及日本第75届法医学学术年会,并在大会上作学术报告.吴梅筠教授现为华西医科大学法医学系教授,硕士、博士导师,省级重点学科学术带头人,昆明医学院客座教授,国家教委"法医学专业教育指导委员会”委员、中国法医学会理事、中国法医学会法医物证专业委员会副主任委员、四川省法医学常务理事及法医物证检验委员会主任委员、四川省法医学技术鉴定委员会委员、<中国法医学杂志>副主编及英文编审、<华西医科大学学报>及<中国输血杂志>编委.1991年享受国家特殊津贴.吴梅筠教授长期从事病理学和法医学的教学、科研及检案工作,为中国法医学事业,特别是华西科大学法医学系的建设、学科的发展和人才培养作出了巨大贡献.     

短串联重复vWFⅢ扩增片段长度多态性在法医学应用的可行性研究

目的 探讨ＳＴＲ位点ｖＷＦⅢ用于法医学鉴定中的实用价值。方法 应用聚合酶链式反应（ＰＣＲ），聚丙烯酰胺凝胶电泳结合染银显带的分离方法对ＳＴＲ位点ｖＷＦⅢ扩增片断长度多态性进行研究。结果 经过优化筛选掌握了该位点的最适扩增条件，其对各类检材均获得可靠的扩增产物。本方法的灵敏度达１０ｐｇ基因组ＤＮＡ、０．５μｌ全血、１μｌ新血痕、０．１μｌ精液、０．２μｌ新鲜精斑。结论 本方法快速、灵敏、准确，在法医     

个体识别SNPs位点组合筛选与法医学应用价值初探

目的筛选用于包括中国主要民族在内的多个群体个体识别的SNPs位点组合体系。方法以Kidd实验室筛选的86个SNPs位点、欧洲SNPforID组织构建的52-plex SNPs复合检测体系为基础,收集和整理这些位点在HapMap数据库中11个人群的分型数据,计算各位点杂合度和Fst值,筛选杂合度〉0.4,Fst值〈0.06,并在研究人群中处于Hardy-Weinberg和连锁平衡的位点组合。针对这些位点,采用MassARRAY分子阵列技术对自行收集的8个人群（尼日利亚人、坦桑尼亚查加人、印度人、丹麦人、俄罗斯汉特人、中国汉族、藏族、维吾尔族）308份样本进行分型,统计群体遗传学参数。结果按本文标准共筛选出66个SNPs位点,均符合Hardy-Weinberg平衡,之间互不连锁,平均杂合度和Fst值分别为0.475、0.014。在本文收集的8个人群中的随机匹配概率在1.45E-24~4.72E-27之间,累积非父排除率为0.999 995 608~0.999 997 876之间。结论本文筛选的SNPs组合系统具有较强的个体识别能力,可用于本文调查的HapMap数据库中11个人群和本文收集的8个人群的个体识别鉴定。     

Population genetic data of eight tetrameric short tandem repeats (STRs) in Casablanca resident population to use in forensic casework

The allele frequencies for eight short tandem repeat (STR) loci HUMvWA, HUMFES/FPS, HUMF13A, HUMF13B, HUMTHO1, HUMTPOX, HUMCSF1P0, HUMLPL included in Geneprint STR kits were obtained from 234 unrelated individuals in Casablanca.     

Immunological analysis of human placental lactogen in blood stains and its application to forensic science

Sex determination of blood stains from women who were in the late stages of pregnancy was possible by detecting human placental lactogen (HPL) in them. However, the agglutination time for positive reactions was prolonged as the stains aged.     

The polymerase chain reaction and post-mortem forensic identity testing: application of amplified D1S80 and HLA-DQ alpha loci to the identification of fire victims.

The application of DNA typing methods after amplification by the polymerase chain reaction (PCR) of DNA derived from body tissues from charred fire victims was investigated. A total of 26 different tissue specimens from ten extensively burned individuals were analyzed. The samples included femoral muscle, psoas muscle, bone marrow and blood. The post-mortem period varied from 38 to 183 h. After amplifying the DNA by PCR from the various tissues, the D1S80 locus was analyzed with a high resolution polyacrylamide gel electrophoresis technique followed by silver staining and the alleles of the HLA-DQ alpha locus were detected by using a reverse dot blot format. All samples could be typed for both loci and the genotypes were consistent in the various tissues from each individual. A parentage test was performed in two cases and Mendelian inheritance of the alleles for both loci was observed.     

Validation of short tandem repeats (STRs) for forensic usage: performance testing of fluorescent multiplex STR systems and analysis of authentic and simulated forensic samples

The amplification and typing conditions for the 13 core CODIS loci and their forensic applicability were evaluated. These loci are CSF1PO, FGA, TH01, TPOX, vWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, and D21S11. Results were obtained using the multiplex STR systems AmpFlSTR Profiler Plus and AmpFlSTR COfiler (Applied Biosystems, Foster City, CA), GenePrint PowerPlex (Promega Corporation, Madison, WI), and subsets of these kits. For detection of fluorescently labeled amplified products, the ABI Prism 310 Genetic Analyzer, the ABI Prism 377 DNA Sequencer, the FMBIO II Fluorescent Imaging Device, and the Fluorlmager were utilized. The following studies were conducted: (a) evaluation of PCR parameter ranges required for adequate performance in multiplex amplification of STR loci, (b) determination of the sensitivity of detection of the systems, (c) characterization of non-allelic PCR products, (d) evaluation of heterozygous peak intensities, (e) determination of the relative level of stutter per locus, (f) determination of stochastic PCR thresholds, (g) analysis of previously typed case samples, environmentally insulted samples, and body fluid samples deposited on various substrates, and (h) detection of components of mixed DNA samples. The data demonstrate that the commercially available multiplex kits can be used to amplify and type STR loci successfully from DNA derived from human biological specimens. There was no evidence of false positive or false negative results and no substantial evidence of preferential amplification within a locus. Although at times general balance among loci labeled with the same fluorophore was not observed, the results obtained were still valid and robust. Suggested criteria are provided for determining whether a sample is derived from a single source or from more than one contributor. These criteria entail the following: (a) the number of peaks at a locus, (b) the relative height of stutter products, and (c) peak height ratios. Stochastic threshold levels and the efficiency of non-templated nucleotide addition should be considered when evaluating the presence of mixtures or low quantity DNA samples. Guidelines, not standards, for interpretation should be developed to interpret STR profiles in cases, because there will be instances in which the standards may not apply. These instances include (a) a primer binding site variant for one allele at a given locus, (b) unusually high stutter product, (c) gene duplication, and (d) translocation.     

A polymerase chain reaction (PCR) method for sex and species determination with novel controls for deoxyribonucleic acid (DNA) template length.

Human X and Y chromosome alpha-satellite sequences lying within higher order repeats were amplified by the polymerase chain reaction (PCR) in genomic deoxyribonucleic acid (DNA) isolated from blood, bone, and several other tissues and specimens of potential forensic science interest. X and Y sequences could be coamplified under some of the PCR conditions employed. Monomorphic sequences in the 3'-apolipoprotein B gene (designated "H") and in an alpha-satellite higher order repeat on Chromosome 17 (p17H8, D17Z1) were likewise amplified in the specimens. X and Y sequence amplification can provide information about the sex of origin. Amplification of the X, H, and D17Z1 sequences was found to be primate-specific among the common animals tested and can thus provide species of origin information about a specimen. The authors suggest that amplification of X and D17Z1 or H sequences might provide "relaxed" and "stringent" controls for appropriate PCR amplification tests on forensic science specimens. Testing was carried out using PCR protocols that employed Thermophilus aquaticus (Taq) and Thermus flavis (Replinase) thermostable DNA polymerases.     

Context effects in forensic science: a review and application of the science of science to crime laboratory practice in the United States.

This article discusses the phenomenon of "context effects" by reviewing the findings and practices of a range of scientific fields, including astronomy, physics, biology, medicine, and especially the relevant research and theory from psychology. Context information, such as expectations about what one is supposed to see or conclude, has been found to have a small but relentless impact on human perception, judgment, and decision-making. The article then considers the vulnerability of forensic science practice to context effects, and concludes by suggesting that forensic science adopt practices familiar in other fields of scientific work, in particular blind or double-blind testing and also the use of evidence line-ups.     

广东地区汉族人群 13个 STR基因座的频率调查

目的调查广东地区汉族无关个体的 13个 STR基因座（ D3S1358、 vWA、 FGA、 D8S1179、 D21S11、 D18S51、 D5S818、 D13S317、 D7S820、 D1 6S539、 TH01、 TPOX、 CSF1PO）多态性,研究其在法医学检验中的应用价值。方法用 AmpFlSTR Profiler Plus及 Cofiler二个荧光标记系统对新鲜血样进行 13个基因座的复合扩增,用 ABI 377-96全自动测序仪对扩增产物进行检测,用 GenoTyper软件进行基因分型。结果 13个基因座 PIC >0.5,DP >0.76,家系调查符合孟德尔遗传规律。结论含有 13个 STR基因座的二个荧光标记复合扩增系统可满足法医物证学的个体识别及亲权鉴定的需要。     

荧光复合扩增4个Y染色体STR的单倍型及其法医学应用

目的建立一套Y染色体STR的双色荧光复合扩增系统,调查4个Y-STR基因座单倍型分布情况及其在混合斑物证检验中的法医学应用前景。方法荧光标记引物复合扩增Y-GATA-A10、DYS531、DYS557和DYS448四个Y染色体特异性STR基因座,并用ABⅠ310遗传分析仪对扩增产物进行检测、分型。结果在成都汉族120名无关男性个体中,四个基因座分别检出5、5、8、7个等位基因,共检出78种单倍型,单倍型基因多样性为0.9881。对3例本教研室不能用常规常染色体STR对男性成份作出同一认定的混合斑检材,该系统成功的作出了与嫌疑人血液Y-STR基因型一致的鉴定结论。结论建立的Y-STR荧光标记复合扩增系统具有很高的识别能力,对建立Y染色体STR数据库,研究群体遗传学和进行法医学混合斑物证鉴定有重要意义。     

A study of the precursors, intermediates and reaction by-products in the synthesis of 3,4-methylenedioxymethylamphetamine and its application to forensic drug analysis

3,4-Methylenedioxymethylamphetamine (MDMA) was prepared by three synthetic routes. Analytical data from thin-layer chromatography, gas chromatography and gas chromatographymass spectrometry of the precursors (safrole and isosafrole), intermediates (isosafrole glycol, piperonylmethylketone, N-formyl-3,4-methylenedioxymethylamphetamine, N-formyl-3,4-methylenedioxyamphetamine and 1-(3,4-methylenedioxyphenyl)-2-bromopropane), reaction by-products and the product MDMA were obtained. Further analyses of MDMA using other techniques including ¹H- and ¹³C-nuclear magnetic resonance spectroscopy, X-ray diffraction, infrared spectroscopy, ultraviolet spectroscopy and high performance liquid chromatography were also carried out. The results were then used as reference data for the identification of MDMA in case samples and also to establish the route of synthesis of illicity prepared MDMA by the study of trace impurities.