微型DNA指纹图的研究与应用

作者采用小板琼脂糖凝胶电泳,应用MYO探针,Southern印迹杂交技术制作微型DNA指纹图,能获得清晰图谱。实验结果表明,同一个体的血液与血斑,精液与精斑及不同部位的组织,其指纹图谱完全相同。不同个体的微型DNA指纹图谱有明显个体差异。用本法能使大板DNA指纹图的常规检出量重复15～20次,最小检出量为250ng,达到极微量的水平。     

JL-02多位点探针DNA指纹的法医学应用研究

以自制的JL－02探针进行了DNA指纹分析，对北京地区无关个体进行了调查，计算出任意两无关个体的偶合机率为6．6×10－15；家系分析表明，谱带在亲代与子代间的传递符合孟德尔遗传规律；同一个体不同组织的DNA指纹图相同；混合斑精子DNA指纹图与相应男性血液DNA指纹图完全相同；该探针对0．5μg的基因组DNA杂交，可获得清晰可辩的DNA指纹图。证明了新探针适用于法医物证检验中的个人同一认定及亲子鉴定。     

DNA指纹图在法医学鉴定中应用的研究(Ⅲ)——应用“Myo”DNA探针进行混合斑中精液的个体认定

本文利用蛋白酶K、SDS对精液和阴道液、精液和血液的混合斑进行前处理,除去女性阴道脱落上皮细胞和血液细胞成份获得精子。提取精子DNA,用“Myo”小卫星DNA探针杂交进行DNA指纹检验,获得了高度多态性的精子DNA指纹图谱,与同一个体血液DNA指纹图谱比较完全一致,实现了混合斑中精液来源的个体认定。在对20多起强奸案例混合斑的实际应用中,成功地认定了强奸罪犯。     

DNA指纹图在法医学鉴定中应用的研究(Ⅰ)

应用 MYO DNA 探针对中国人进行了 DNA 遗传指纹图检验。从两个家系16人及100个无关个体中取肘静脉血提取 DNA,用限制性内切酶 HinfⅠ或 HaeⅢ水解,1%琼脂糖凝胶电泳分离,经 Southern印迹转移,MYO DNA 探针杂交,获得了清晰可辨的 DNA 指纹图谱。结果每个个体在3.0Kb 以上均能检出10条以上杂交区带,个体间的相关概率<4×10~(-9),由杂交区带构成的图谱是个体特异的,杂交区带遵循孟德尔的显性遗传方式由亲代向子代遗传;具有 DNA Fingerprints 的特点。对两起亲子鉴定的案例进行指纹图检验,孩子所存在的杂交区带,除来自母亲外,其余可在嫌疑父亲带中找到,肯定了孩子与嫌疑人的父子关系。MYO DNA 探针在亲子鉴定与个人识别的法医学鉴定中有着重要的实用价值。     

DNA分析及其在法庭科学中的证据作用

在DNA分析技术应用于法医物证检验之前,法医物证技术只能对血液、精液、血斑、精斑、毛发、唾液斑等人体组织做有限的几种红细胞血型、酶型、血清蛋白型的检验,对血型不同的嫌疑人做出排除的结论,而血型相同时却达不到确认作案人的要求。1985年英国Leister大学遗传学部的Jeffreys首先将DNA分析技术应用于法医物证检验,为法医物证检验提供了新的检验方     

PuriTyper~(TM)法医学纯化试剂盒的性能验证

目的验证PuriTyperTM纯化试剂盒各项性能指标和法医学应用价值。方法收集及制备抗凝血液、常见案件检材(唾液、烟头、精液、毛发、指甲、骨骼及组织块)、斑痕样本(血斑、唾液斑、精斑)以及模拟添加抑制剂和模仿自然环境中放置的血斑。采用PuriTyperTM纯化试剂盒提取纯化并进行DNA定量,IdentifilerTM复合扩增试剂盒扩增,产物经ABI 3130遗传分析仪进行检测,Genemapper软件分析结果,对该试剂盒灵敏度、稳定性、重复性、检材适应性进行测试。结果采用该试剂盒提取0.1～40μL血液分别获得0.042～26.45ng/μL的DNA。3种斑痕样本DNA产量平行试验结果稳定。不同类型检材重复检验所获IPC的CT平均值在27.60至28.03之间。常见案件检材所得分型与已知结果均一致。结论 PuriTyperTM纯化试剂盒能够满足法医DNA检验的要求,对法医学实践具有重要的应用价值。     

33.15及33.6探针对中国人DNA指纹图的研究

目的统计用33．15及33．6探针对中国人进行DNA指纹图检验的群体调查资料，为实际案件的检验提供理论依据。方法应用33．15及33．6探针为中国北京地区无关群体的血液进行DNA指纹图分析。结果应用33．15探针检验15人的DNA指纹图，无关个体间相关机率为1．03×10-15，两无关个体间出现同一谱带的平均概率0．176；应用33．6探针检验19人的DNA指纹图，无关个体间相关机率为1．53×11-11，两无关个体间出现同一港带的平均概率为0．187；两探针均符合孟德尔遗传规律，均具有组织同一性。结论本研究结果可应用于法医物证检验的亲子鉴定及个体识别。     

DNA检验技术在刑事案件中的应用

１凶杀案凶杀或盗窃案现场,有价值的物证常常是被害人或罪犯留下的血迹,通过DNA检验结果计算出现场血迹在种族人群中的偶合机率,如果达到（１０－９～１０－１５）,就可科学准确的表现是否可同一认定。即使是混合血迹（或混合精斑）也不再是不可逾越的障碍。例１,１９９９年５月３０日凌晨,在北京市石景山区发生了一起８名女青年被杀的特大凶杀案。从现场提取８０余处血迹与８名受害人血液样本,同时进行检验。经多个STR位点检验得出：第１,现场血迹与８名死者血样的检验结果进行比对,使每一处血斑均确定是何人所留,从而明确案…     

DNA技术在法医学上的应用

<正> 1985年,英国某地连续发生数起强奸案没能侦破,但调查发现这些案件的作案特点非常相似。后来又一名妇女遭强奸时,其阴道内容物精斑被送往Leicester大学遗传学研究人员Jeffreys等人做“DNA指纹”检验,并将所有涉嫌对象的血样做同样检验,发现其中一嫌疑人的“DNA指纹”与被害人阴道内精斑的“DNA指纹”完全相同,从而认定了罪犯,侦破了此案。此乃利用“DNA指纹”进行法医学个体识别的开端。     

用α-珠旦白-3’HVR探针研究DNA指纹

用α-珠蛋白-3’HVR探针,经Southern印迹法,对100名不相关个体及4个家系的32名相关个体的DNA指纹进行了检测,所产生的DNA图谱具有高度的个体特异性,在被测的所有个体中无一相同。经统计学计算表明,任意两个个体DNA指纹图重合率为10~(-11)。家系分析毒明,DNA片段严格按照孟德尔方式遗传。该探针的应用,将在法医学亲子鉴定和个人同一认定中发挥重要的作用。     

A Comparison of DNA Extraction Using AutoMate Express™ and EZ1 Advanced XL from Liquid Blood,Bloodstains, and Semen Stains

In this study, DNA was extracted using an AutoMate Express? and an EZ1 Advanced XL from liquid blood, fresh and aged bloodstains, and fresh and aged semen stains. Extracted DNA was quantified by real‐time PCR using the D17Z1 locus. Short tandem repeat typing was performed using an AmpF?STR^® Identifiler kit. The yields of DNA obtained by the AutoMate Express? were higher from fresh bloodstains and fresh semen stains, almost the same from aged bloodstains and aged semen stains, but slightly lower from liquid blood compared with those obtained by the EZ1 Advanced XL. The addition of dithiothreitol or the use of PrepFiler? lysis buffer improved the EZ1 Advanced XL results from fresh bloodstains, but not for liquid blood and aged bloodstains. Our results demonstrated that the PrepFiler? lysis buffer is the main contributor to the higher DNA yields of the AutoM ate Express? for fresh bloodstains.     

Evaluation of four deoxyribonucleic acid (DNA) extraction protocols for DNA yield and variation in restriction fragment length polymorphism (RFLP) sizes under varying gel conditions.

This study originated from discussions and recommendations of the Technical Working Group on DNA Analysis Methods (TWGDAM). Four bloodstain deoxyribonucleic acid (DNA) extraction protocols and five semen stain DNA extraction protocols were evaluated. Nine laboratories participated in the extraction of DNA from 20 bloodstains and 20 semen stains using each protocol. All blood and semen stains originated from a single donor and were prepared under uniform conditions to permit the direct comparison of DNA yields and restriction fragment lengths. The extracted DNA from approximately 600 bloodstains and 700 semen stains was quantified by yield gel analysis and a slot blot hybridization technique. The extracted DNA was digested and restriction fragment length polymorphism (RFLP) patterns were generated using three single-locus probes. The RFLP sizing data produced from the blood and semen stains were evaluated with respect to (1) DNA extraction method, (2) gel length, (3) agarose type, (4) presence or absence of ethidium bromide in the gel, and (5) fragment sizes obtained from DNA isolated directly from the donor's liquid blood. This study demonstrates conclusively that high-molecular-weight DNA can be isolated using either organic or nonorganic DNA extraction protocols and that the resulting RFLP sizes are highly reproducible regardless of gel length, agarose type, or presence/absence of ethidium bromide.     

Isolation of deoxyribonucleic acid (DNA) from saliva and forensic science samples containing saliva.

Saliva and saliva-stained materials were examined as potential sources of deoxyribonucleic acid (DNA) for DNA analysis and identity testing. In this paper, the authors demonstrate that DNA was isolated and DNA banding patterns suitable for DNA typing were obtained from fresh saliva and various saliva-stained materials, such as envelopes, buccal swabs, gags, and cigarettes. Furthermore, DNA and DNA banding patterns were obtained from actual forensic evidentiary samples containing mixed saliva/semen stains. The DNA banding patterns obtained from saliva or saliva-stained material were indistinguishable from the patterns obtained from blood or hair from the same individual. Intact DNA was readily isolated and DNA banding patterns were obtained from saliva stored at -20 degrees C and dried saliva stains stored under varying conditions. We conclude that saliva and saliva-stained material can be good sources of DNA for analysis and for DNA typing in certain forensic settings.     

Effects of presumptive test reagents on the ability to obtain restriction fragment length polymorphism (RFLP) patterns from human blood and semen stains.

Some of the commonly used presumptive test reagents for identification of blood and semen could potentially affect the recovery of intact high-molecular-weight deoxyribonucleic acid (DNA) from evidentiary samples. Thus, the capability of performing restriction fragment length polymorphism (RFLP) analysis on evidentiary samples could be compromised. In order to investigate the potential effects of presumptive test reagents on the DNA present in these samples, bloodstains on cotton and glass were exposed directly to luminol, benzidine, phenolphthalein, o-tolidine, and leucomalachite green, while semen stains and vaginal swabs containing semen were exposed directly to bromochloroindolyl phosphate (BCIP) and sodium thymolphthalein monophosphate (STMP) reagents. The yield gels for DNA quality and quantity and RFLP results indicated that bloodstains exposed to luminol, benzidine dissolved in ethanol, and phenolphthalein, as well as semen stains and vaginal swabs exposed to BCIP and STMP yield RFLP patterns consistent with that of the uncontaminated control. Except for the phenolphthalein treatment, the quantity of extractable, high-molecular-weight DNA obtained was comparable with that of untreated stains. Therefore, evidentiary material purposely or inadvertently contaminated with these reagents can be successfully typed. However, stains exposed to benzidine dissolved in glacial acetic acid, leucomalachite green, and o-tolidine failed to yield high-molecular-weight DNA or to produce any RFLP patterns.     

Validation of PrepFiler™ forensic DNA extraction kit (Applied Biosystems)

The PrepFiler™ is a new kit recently introduced by Applied Biosystems for DNA extraction from a wide range of forensic samples. In the present study we tested the performance of PrepFiler™ kit against other commonly used commercially available kits on a variety of real forensic casework samples: bloodstains on different substrates, washed bloodstains, semen stains, saliva stains, hairs, bones, tissues, nails, prints after chemical treatments, skin swabs.     

中国人精子黄递酶Ⅲ型的分布及精斑黄递酶Ⅲ型的检出

应用超薄层聚丙烯酰胺凝胶等电聚焦技术对辽宁地区200例正常人精子黄递酶Ⅲ型(DIA)的分布进行了研究。其基因频率分别为DIA_3~1=0.6850,DIA_3~2=0.2875,DIA_5~3=0.0275。由阴道液、唾液、乳汁及无精子症精液不能判定DIA_3型。室温保存精斑可检出时限为9个月。     

用Y—染色体特异DNA探针鉴识微量干血痕性别的研究

法医鉴识干血痕性别,通常是用盐酸阿地平染色观察 Y—小体的方法。重组 DNA 技术的发展与应用,为法医物证检验开辟了新的领域。本文用 Y—染色体特异 DNA 探针鉴识干血痕性别的成功,为法医的血痕性别签定,提供了一种新的检验方法。     

Developmental Validation of the PrepFiler™ Forensic DNA Extraction Kit for Extraction of Genomic DNA from Biological Samples*

Abstract: The PrepFiler? Forensic DNA Extraction Kit enables isolation of genomic DNA from a variety of biological samples. The kit facilitates reversible binding of DNA with magnetic particles resulting in high DNA recovery from samples with very low and high quantities of biological materials: 0.1 and 40 μL of human blood (donor 2) provided 14 and 2883 ng of DNA, respectively. Following the revised SWGDAM guidelines, performance of the developed method was investigated using different sample types including saliva on swabs, semen stains on cotton fabric, samples exposed to environment, samples with polymerase chain reaction (PCR) inhibitors, blood stains (on denim, cotton cloth, and FTA^® paper), and touch evidence‐type samples. DNA yields for all samples tested were equal or better than those obtained by both phenol–chloroform extraction and commercial kits tested. DNA obtained from these samples was free of detectable PCR inhibitors. Short tandem repeat profiles were complete, conclusive, and devoid of PCR artifacts.     

混合血迹中不同个体成份逐一分离识别的研究

目的研究法庭科学混合血迹物证中不同个体成份逐一分离、识别的问题,建立适合混合血迹个体识别的分析技术。方法采用PCR-SSCP及测序技术,选择m tDNA D-loop区的HVI 16030~16481区域452 bp片段作为分析目标,对中国汉族两无关个体、三无关个体混合血迹进行分析。结果100份两个体混合血迹样品m tDNA 452bp的PCR产物经SSCP电泳分离,结果有95份样品完全分离开,分离成功率达95%;30份三个体混合血迹样品452 bp片段经SSCP电泳分离,结果有26份样品有1~3个个体完全分离开,分离成功率达84%。对其中3份两个体混合血样、2份三个体混合血样SSCP电泳分离后的谱带进行回收、测序分析,两个体混合血样每一份均可准确获得其中单一个体序列及以另一个体主要成份(峰值比达4∶1以上)的序列结果;三个体混合血迹中不同个体成份可以达到初步分离,1份可准确确定单一个体序列。对两个体不同比例混合样品SSCP分析,结果可以检测到较少成份的最低比例为20∶80。结论本研究建立的PCR-SSCP及测序分析混合血迹综合技术,是对混合血迹中不同个体成份逐一分离、识别的一种有效技术手段。