PCR-STR分型技术在尿样DNA分型中的应用

目的　对尿样的DNA分型进行研究。　方法　 10份尿样随机收集于无关个体 ,同时采集血液样本做DNA分型对照 ,用PCR -STR分型技术对尿样DNA进行FIBRA和D18S5 35基因座分型。　结果　 10份尿样 10ml、1ml及 0 .2ml体积均获得准确的分型结果 ,且与同一个体的血样DNA分型结果完全相同 ;室温储存 4天及 4℃保存 4周的尿样均分型成功。　结论PCR -STR分型技术对尿样DNA分型是一种有效的方法 ,在尿样的个人识别中具有极高的实用价值。     

澳大利亚联邦警察局法医DNA实验室管理与质量控制简介

在国家留学基金委资助下,笔者于2011年作为国家公派访问学者赴澳大利亚联邦警察局（Austral—ianFederalPolice,简称AFP）法医及数据中心（Fo—rensicandDataCentre）交流学习。本文重点介绍最新的澳大利亚联邦警察局法医DNA实验室管理的基本情况及其目前质量控制（QualityControl,简称QC）的主要措施,结合我国的实际国情及法医DNA实验室管理及发展现状,探讨我国可以借鉴的法医DNA实验室管理制度、运行机制、质量管理等方面先进经验,供同行们借鉴和参考。     

赴美国考察DNA数据库及DNA实验室的情况介绍

美国联邦调查局（FBI）邀请,公安部刑事侦查局组团于2009年7月19日至25日赴美国对FBI、加利福尼亚州（以下简称“加州”）和巴尔蒂摩市（以下简称“巴市”）DNA实验室进行了考察。本文重点介绍了美国DNA实验室、DNA数据库建设应用的基本情况,探讨了其先进经验给我们的启示,     

从打火机上提取DNA成功分型1例

2009年8月在某市发生一起盗窃保险柜案件,勘查人员在勘查现场时在被撬开的保险柜中发现一支一次性打火机,怀疑是犯罪嫌疑人所留。为明确案情,将打火机送检,并成功对其表面提取的DNA进行了STR分型。     

法庭科学DNA实验室规范化建设的初体验

近几年来,法庭科学DNA分析技术及其数据库建设在国内发展迅速,各类刑事案件的侦破及法庭举证中该技术的应用日趋广泛。各地法医DNA实验室检验量持续增加,专业技术人员长期超负荷工作,鉴定质量难以保障,已成为普遍面临的问题。因此,尽快开展法庭科学DNA实验室的规范化建设显得尤为重要。现将本实验室开展规范化建设情况及工作中的体会介绍如下,供同行交流、参考。1天津市法医DNA实验室规范化建设情况本实验室自1990年组建以来,历经RFLP、VN-TR、STR等法医DNA分析技术各个发展时期的磨砺,逐步走上了标准化、规范化的发展轨道。针对…     

指纹和DNA分型证据的比较研究

本文在简要地叙述了指纹证据和DNA历史的基础上,介绍了两个法庭证据在技术上的运用并讨论了两个领域相关专业知识的界限和构成。指纹证据拥有独特的说服力来让陪审员定被告的罪。DNA分型研究渗入了主流媒体,尽管它可以明显地辨认嫌疑犯,但DNA分型研究的证据性还是在法庭上遭到质疑。本文将比较指纹证据和DNA分型研究,通过比较分析从而可以让实习者、法官和律师们注意到指纹证据作为黄金证据的缺点。     

法医DNA实验室污染问题分析与对策

法医物证学;DNA污染;防控措施     

PCR-STR分型技术在尿样DNA分型中的应用

目的：对尿样的DNA分型进行研究。方法：10份尿样随机收集于无关个体,同时采集血液样本做DNA分型对照,用PCR－STD分型技术对尿样DNA进行FIBRA和D18S535基因座分型。结果：10份尿样10ml、1ml及0．2ml体积均获得准确的分型结果,且与同一个体的血样DNA分型结果完全相同;室温储存4天及4℃及4周的尿样均分型成功。结论：PCR－STR分型技术对尿样DNA分型是一种有效的方法,在尿样的个人识别中具有极高的实用价值。     

法医DNA实验室的DNA污染和防范

DNA污染是产生DNA鉴定结论错误的重要因素,法医DNA实验室要努力去解决这一问题。DNA污染有自身污染、交叉污染、PCR污染3种。法医DNA实验室要采取实验室分区、严格检验操作步骤、对试剂及消耗材料进行质量控制等方法防止发生DNA污染,采取设置对照样本、核查DNA结果、建立DNA排查数据库等方法监测和发现DNA污染。     

牙齿的DNA提取及STR分型研究

目的建立有效的牙齿DNA提取方法。方法使用物理及化学方法去除牙齿表面污染物,经脱钙、裂解、纯化从牙粉中提取DNA进行STR分型。结果对96例牙齿检材进行DNA检验,获得STR分型的有94例,在查找尸源的案件中发挥了重要作用。结论本方法操作简单快速,能够显著提高牙齿DNA检验的成功率。     

物证鉴定实验室的组织和服务体系

世界各国物证鉴定实验室组织结构有多种形式。本文综述了物证鉴定实验室的内部组织、上级组织和服务体系模式 ,分析讨论各种模式的特性和优缺点。物证鉴定实验室组织形式由多种因素决定 ,没有最佳模式     

论法庭科学实验室认可的特殊要求

本文从价值观、证据资格和优质法庭科学服务3个方面分析了法庭科学实验室认可特殊性的产生根源;分析和总结了ILAC和部分国家法庭科学实验室认可的特殊要求,给此项工作在我国的开展提供了借鉴。     

Assessing the potential of bacterial DNA profiling for forensic soil comparisons

A pilot study was undertaken to evaluate DNA profiling of the bacterial community in soil as an alternative to geological methods for forensic soil comparisons. Soil samples from three different ecosystems were compared, and the variation within and between ecologically different sites was determined by using terminal restriction fragment (TRF) analysis of 16S ribosomal DNA. Comparison of TRF profiles revealed that samples from within a specific ecosystem (e.g., a field) showed a significantly higher similarity to each other than to those from another ecosystem (e.g., a forest). In addition, some profile features were unique to specific ecosystems. These features may allow the determination of characteristic profiles that will facilitate identification of ecologically different sites, so that a given sample collected from a suspect could be identified as originating from, for example, a field, rather than a forest. The implications of these preliminary findings for forensic investigations are discussed.     

The utility of whole genome amplification for typing compromised forensic samples

Biological evidence has become invaluable in the crime laboratory; however, it may exist in limited quantity and/or quality. Given this, the ability to amplify total DNA obtained from evidence, in an unbiased manner, would be highly advantageous. Methods for whole genome amplification (WGA) have the potential to fulfill this role, resulting in a virtually unlimited supply of DNA. In the research presented, two WGA methods, improved primer extension preamplification and multiple displacement amplification (MDA), were tested using commercial kits. Control DNA, artificially degraded DNA, and DNA from fresh blood, aged blood, hair shafts, and aged bones underwent WGA, followed by short tandem repeat and mitochondrial DNA analysis. The methods did amplify DNA, but performed poorly on forensically relevant samples; the maximum amplicon size was reduced, and MDA often resulted in extraneous bands following polymerase chain reaction. Taken together, WGA appears to be of limited forensic utility unless the samples are of a very high quality.     

国外法庭科学DNA实验室的质量保证和质量控制现状

法庭科学DNA检测飞速发展和广泛应用的同时也面临巨大风险,实验室质量保证能力和质量控制手段的不足已开始影响到法庭科学DNA检测的证据地位。本文对国外法庭科学DNA实验室的有关情况进行初步分析,从中发掘有益的启示,为我国法庭科学DNA检测的改革和发展提供借鉴。     

Mitochondrial DNA sequencing of cat hair: an informative forensic tool

Approximately 81.7 million cats are in 37.5 million U.S. households. Shed fur can be criminal evidence because of transfer to victims, suspects, and/or their belongings. To improve cat hairs as forensic evidence, the mtDNA control region from single hairs, with and without root tags, was sequenced. A dataset of a 402-bp control region segment from 174 random-bred cats representing four U.S. geographic areas was generated to determine the informativeness of the mtDNA region. Thirty-two mtDNA mitotypes were observed ranging in frequencies from 0.6-27%. Four common types occurred in all populations. Low heteroplasmy, 1.7%, was determined. Unique mitotypes were found in 18 individuals, 10.3% of the population studied. The calculated discrimination power implied that 8.3 of 10 randomly selected individuals can be excluded by this region. The genetic characteristics of the region and the generated dataset support the use of this cat mtDNA region in forensic applications.     

ABO基因分型与多重STR联合检测在法医学中的应用

目的建立ABO基因型和Goldeneye16A试剂盒联合检测的方法,并评价其在法医学实践中的应用价值。方法将6种ABO基因型(A/A,A/O,B/B,B/O,A/B,O/O)的序列特异性引物(PCR-SSP)检测方法与Goldeneye16A试剂盒相整合进行同步分型。通过对460份男性个体血痕样本、9947A DNA及90份案件样本进行检测,考察方法的一致性、灵敏度及对法庭科学检材的适用性。结果应用本文方法可同时检出6种ABO基因型和15个常染色体STR基因座及性别决定基因座,检测灵敏度为125pg,其中ABO基因检测灵敏度达63pg。460份男性血痕和90份案件检材证实该联合分型方法用于各类检材结果准确、稳定。结论本文ABO基因分型与多重STR联合检测方法,适用于各类含有核细胞的生物检材,在法庭科学DNA鉴定中有较好的应用前景。     

我国法庭科学实验室管理中的问题与对策

本文从管理体制和运行机制两个层面对国内外法庭科学实验室的管理工作进行了综述,深入探讨并分析了我国现有实验室管理中存在的问题,并有针对性的提出了政策建议。     

Y-STRs in forensic medicine: DNA analysis in semen samples of azoospermic individuals

ABSTRACT: The incidence of rape has increased, especially in metropolitan areas, such as the city of São Paulo. In Brazil, studies about it have shown that the majority of this type of crime is committed by the relatives and persons close to the victim. This has made the crime more difficult to be denounced, as only 10% of the cases are reported to competent police authorities. Usually, cytological exams are carried out in sex crime investigations. The difficulty in showing the presence of spermatozoa is frequent, but it does not exclude the presence of male DNA. The absence of spermatozoa in material collected from rape victims can be due to several factors, including the fact that the agressor suffers from azoospermia. This condition can be the result of a successful vasectomy. As the majority of DNA in the ejaculation sample is from spermatozoa, there is much less DNA to be analyzed. This study presents the application of Y‐STRs (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, and DYS393) in DNA analysis of sperm samples from 105 vasectomized men. The study demonstrated a great variation in DNA concentration. DNA extraction and amplification was possible in all sperm samples even in the absence of spermatozoa. The same profile was observed, for each individual, from DNA extracted from blood, pre‐ and postvasectomy semen samples. The use of markers specific for Y chromosome in sex crime cases, especially in the absence of spermatozoa, is very important, mainly because in most situations there is a small quantity of the agressor's DNA in the medium and a large quantity of the victim's DNA.