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.     

Discrimination between sediment and soil samples for forensic purposes using elemental data: an investigation of particle size effects

This paper reports the results of an investigation to quantify variations in elemental concentrations amongst different particle size fractions obtained from a suite of sediment samples collected from the River Avon, UK. Concentrations of 49 elements determined by inductively coupled plasma spectrometry (ICP-AES and ICP-MS) were compared using conventional and multivariate statistical methods in order to assess compositional differences between different size fractions and between different samples. The results showed significant differences between different size fractions and the bulk sediments, but indicated that all of the size fractions considered (<150, 63-150, 20-63 and <20microm) provided an adequate basis on which to identify associations and differences between samples. It was concluded that, while in certain specific circumstances it may be most appropriate to make forensic comparisons based on a very narrowly defined particle size range, for the majority of purposes the <150microm fraction provides the best compromise between sample size requirements and data resolution.     

菲德倍斯试剂检验唾液斑的有效性

目的验证菲德倍斯试剂（Phadebas Forensic tube test）检验唾液（斑）的有效性。方法从灵敏度、敏感性、常见载体的影响、唾液斑保存时间的影响,以及与STR检验的相关性等几个方面进行研究。结果0.01 ul唾液和阴干保存1年以上的唾液斑仍能被有效检出,该检验对其它常见体液（斑）反应不敏感,常见载体对该检验无影响。结论菲德倍斯试剂是人唾液（斑）检验的理想试剂。     

The forensic application of allozyme electrophoresis to the identification of blowfly larvae (Diptera: Calliphoridae) in southern Australia

Most known carrion-breeding species of blowflies in southern Australia are of the genus Calliphora. The morphological similarity of the immatures of these species means that correctly identifying them poses a challenge for forensic entomologists. This study investigates the potential of allozyme analysis to assist with this task. Molecular profiles of third-instar larvae and adults representing four of these carrion-breeding species, Calliphora stygia, C. dubia, C. hilli hilli, and C. vicina, were compared at 42 allozyme loci. The two life stages were found to display almost identical allozyme profiles in each species (93% of loci were expressed in both life history stages), enabling the reliable identification of larvae in these four species. Integration of these results with data from a previous study indicates that allozyme analysis would also be suitable for rapid, species-level identification of the larvae of six other carrion-breeding Calliphora species occurring in southern Australia. This is the first report of the application of allozyme data to the identification of forensically important blowflies.     

The application of signal detection theory to decision-making in forensic science

Signal Detection Theory (SDT) has come to be used in a wide variety of fields where noise and imperfect signals present challenges to the task of separating hits and correct rejections from misses and false alarms. The application of SDT helps illuminate and improve the quality of decision-making in those fields in a number of ways. The present article is designed to make SDT more accessible to forensic scientists by: (a) explaining what SDT is and how it works, (b) explicating the potential usefulness of SDT to forensic science, (c) illustrating SDT analysis using forensic science data, and (d) suggesting ways to gain the benefits of SDT analyses in the course of carrying out existing programs of quality assessment and other research on forensic science examinations.     

超滤管在陈旧生物检材中的应用

目的探讨millipore超滤管滤过方法对陈旧生物检材DNA分型检验的应用价值。方法将23份陈旧血样分别剪取同样合适大小的血片3组,标为A、B、C组,磁珠法提取DNA,分别用80μL、80μL、20μL洗脱液洗脱得到模板DNA,其中A、C组模板直接扩增,B组用millipore超滤管滤过浓缩后扩增。PCR产物用AB3130x L基因分析仪检测,Gene Mapper ID V3.2软件进行自动分型。所得实验数据用SPSS软件分析处理。结果 A组没有1例样本扩出全部STR基因座,B组有18例样本扩出全部STR基因座,C组有11个样本扩出全部STR基因座。结论应用millipore超滤管滤过方法可以明显提高陈旧生物检材的DNA分型成功率。     

Independent forensic autopsies in an armed conflict: investigation of the victims from Racak, Kosovo

In January 1999, a team of Finnish forensic experts under the mandate of the European Union (EU forensic expert team, EU-FET) performed forensic investigations in a sovereign state, in Kosovo, the Federal Republic of Yugoslavia (FRY). The team served as a neutral participant in the forensic investigation of victims of an incident at Racak, which was receiving considerable international attention. The Finnish team performed forensic autopsies, monitored forensic autopsies performed by local experts and verified findings of earlier executed autopsies. The victims had sustained varying numbers of gunshot wounds, which were established to be the cause of death. The manner of death remained undetermined by the EU-FET, because the scene investigation and the chain of custody for the bodies from the site of the incident to the autopsy were impossible to verify by the team. The events at Racak were the first of those leading to charges by the International Criminal Tribunal for the former Yugoslavia (ICTY) against the highest authorities in power in the FRY for crimes against humanity and violations of the laws or customs of war.     

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.     

Evaluation of an enzyme linked immunosorbent assay (ELISA) method for ABO and Lewis typing of body fluids in forensic samples.

An ELISA for the detection of the ABO group and secretor status of body fluids and stains other than blood is described, together with the validation procedures employed before its introduction into forensic casework. Criteria for the interpretation of results have been formulated for the method in use in this laboratory. The method was found to be reliable and to have a higher success rate than the haemagglutination techniques previously employed.     

Practical application of the Injury Severity Score (ISS) in expert forensic testimony

The retrospective analysis of the autopsy records of 50 homicides showed that the Injury Severity Score (ISS), a numerical scoring system initially developed to quantify the severity of injuries sustained in road traffic accidents, can also be useful for objectively describing and ranking the overall severity of trauma with regard to forensic issues. The present case report illustrates to what extent the ISS can help to assess the contribution of each assailant in homicides committed by several perpetrators. In the case presented the court was convinced that one perpetrator had inflicted four deep stab wounds to the victim's face (each with bony lesions), 2 stabs to the chest piercing the right lower pulmonary lobe and causing a haemothorax of 200 ml, an abdominal stab wound without involvement of a parenchymatous organ as well as multiple defence wounds of the arms. Thereafter, a second perpetrator was thought to have inflicted several heavy blows with a full water bottle causing severe contusions on the right side of the forehead, the chin, the left side of the face and a spider's web fracture of the frontal bone. Using the ISS an injury severity score of 24 was assigned to the first complex of injuries and a score of 10 to the second complex. The forensic conclusions with regard to prognosis and lethal outcome are discussed.     

论法医学鉴定文书

概述 一、法医学鉴定文书的概念及其种类 法医学鉴定文书,是指法医学鉴定人接受委托和在检验、鉴定过程中形成的各种规范性文字、数据和图片(像)资料,以及根据检验所见和鉴定结论制作的书面报告的总称,也可以简称为法医学文书.关于法医学鉴定文书的名称问题,在传统法医学中仅见介绍过"法医学鉴定书”一词,而法医学鉴定书是法医学鉴定文书的一种.另外,我国法学界和司法部门使用的"诉讼文书(有称司法文书和法律文书)”与法医学鉴定文书的关系尚需进一步探讨,但诉讼文书中也涉及法医学鉴定文书的内容. 根据法医学鉴定文书的作用、特点,可以将其分为以下几类(如图示),该分类主要包括三个方面,鉴定程序和过程的文字记录;鉴定书;鉴定结论签发手续和应用反馈.     

The United Kingdom and Ireland association of forensic toxicologists forensic toxicology laboratory guidelines (2018)

In 2010, the United Kingdom and Ireland Association of Forensic Toxicologists (UKIAFT) created forensic toxicology laboratory guidelines. This represents a revision of those guidelines as a result of the changing toxicological and technical landscape.     

论法医学鉴定文书

编者按：法医学是为法律服务的一门自然科学，其提供服务是通过鉴定实现的。鉴定在法医学，乃至法庭科学中占有极为重要的位置。然而，由于我国在司法鉴定立法方面很不完善，以及其他众所周知的原因，致使有关法医学鉴定的理论发展缓慢，很不系统，这不仅影响专业教育培养职业鉴定人，而且，也不利于充分发挥法医学鉴定的服务职能。为此，我们提出创建“法医鉴定学”，作为法医学的分支学科。法医鉴定学所涉及的内容较为广泛，其学科框架尚难明确界定。我刊从本期开始设“法医鉴定学”专题栏目，本期两篇文章，旨在抛砖引玉，特别是通常所称…     

尿素氮、肌酐和尿酸死后生化学检测的法医学应用

死后生化学是法医鉴定中重要的检查手段。研究表明含氮化合物中尿素氮、肌酐、尿酸是临床上常用的生化学检测指标,其在法医死后生化学检测中也有重要的价值。本文就体内上述三者的特征及其在法医学中的研究及应用加以综述,以期为法医死后生化学分析提供参考。     

Successful extraction of human genomic DNA from serum and its application to forensic identification

We report here on the successful extraction of human genomic DNA from a serum sample in a forensic case. The extracted DNA was successfully used for the identification of remains presumably immersed for more than three weeks for which the only comparison sample was a 250-microL serum aliquot kept frozen in a laboratory. The analysis made it possible to identify a second victim as the daughter of the first.     

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.     

Analysis of DNA profiles extracted from degraded samples from archival of formalin fixed tissue included in paraffin (FFTIP) and hairs

The possibility of studying DNA extracted from archival of formalin fixed tissue included in paraffin (FFTIP) enables valuable retrospective investigations. However, according to some authors it is difficult to obtain genomic DNA of good quality, since the process of fixation often results in fragmentation of DNA. In order to evaluate the quality and quantity of DNA extracted, necropsy samples of FFTIP (spleen/lung) and hairs, with or without bulbs, were analyzed using three methods of extraction (QIAamp DNA mini, QIAamp DNA micro-kit and phenol–chloroform followed by microcon YM-30). The amount of DNA recovered was quantified by spectrophotometer. The β-actin, amelogenin gene and the profiles of STR were analyzed. Based on experimental results, a general guideline concerning the appropriate extraction method according to the tissue and the quantity of the starting material for the analysis of DNA from FFTIP and hairs could be suggested.     

DYS19、DYS391、DYS439三个Y-STR荧光标记复合扩增的法医学应用研究

目的　研究Y—染色体STR基因座在法医学检测中的应用价值。方法　用荧光标记DYS19,DYS391,DYS4 39三个Y—STR基因座 ,PCR复合扩增 ,通过毛细管电泳得到结果。结果　三个Y—STR基因座有较高的种属特异性 ;观察 5 0次男性配子细胞形成过程中的减数分裂未发现突变基因 ;对男∶女不同比例混合血样检测 ,当男∶女性血样比达 1∶5 0时 ,仍能准确分型Y—STR基因型 ,并且Y—STR检验较常染色体STR分型更有优势 ;检测了 1～ 15个月病理石蜡切片 ,表明Y -STR基因座适合降解DNA的检测。结论　Y -STR分型适合日常法医检案的需要 ,该方法是对常染色体STR应用的一个补充。     

The information gained from witnesses' responses to an initial "blank" lineup

Wells ("The psychology of lineup identifications," Journal of Applied Social Psychology, 1984, 14, 89-103) proposed that a blank lineup (an initial lineup of known-to-be-innocent foils) can be used to screen eyewitnesses; witnesses who chose from a blank lineup (initial choosers) were more likely to make an error on a second lineup that contained a suspect than were witnesses who rejected a blank lineup (initial nonchoosers). Recent technological advances (e.g., computer-administered lineups) may overcome many of the practical difficulties cited as a barrier to the use of blank lineups. Our research extended knowledge about the blank lineup procedure by investigating the underlying causes of the difference in identification performance between initial choosers and initial nonchoosers. Studies 1a and 1b (total, N = 303) demonstrated that initial choosers were more likely to reject a second lineup than initial nonchoosers and witnesses who did not view a blank lineup, implying that cognitive biases (e.g., confirmation bias and commitment effects) influenced initial choosers' identification decisions. In Study 2 (N = 200), responses on a forced-choice identification test provided evidence that initial choosers have, on average, poorer memories for the culprit than do initial nonchoosers. We also investigated the usefulness of blank lineups for interpreting identification evidence. Diagnosticity ratios suggested that suspect identifications made by initial nonchoosers (cf. initial choosers) should have a greater impact on estimates of the likely guilt of the suspect. Furthermore, for initial nonchoosers, higher confidence in blank lineup rejections was associated with higher diagnosticity for subsequent suspect identifications. These results have implications for policy to guide the collection and interpretation of identification evidence. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

The use of quantitative light-induced fluorescence (QLF) to identify composite restorations in forensic examinations

There has been a large increase in the number of tooth colored restorations "white fillings" placed in recent years. An increased demand from the public for more aesthetic dental restorations causes a potential problem for forensic dentists who may find the fillings difficult to identify and hence include in postmortem odontograms. This has implications for the accuracy of dental identifications, particularly in situations where limited time is available for postmortem identification, e.g., mass casualty incidents. A new method for the detection of composite restorations is presented. Quantitative Light-induced Fluorescence (QLF) is a technique currently employed to detect small changes in enamel mineral content. An experiment was conducted to determine if the technique would afford a greater degree of contrast between composite and enamel and thus enable the accuracy of composite identification in enamel. Twenty-four previously extracted human premolars were gently cleaned with pumice and wet-and-dry paper. Twelve were subsequently randomly selected and restored on their buccal surfaces with Spectrum (a composite) following manufacturer's instructions. No attempt was made to color match the teeth and all were filled with shade B3. Twelve teeth were left unrestored. QLF and normal white light images were taken of both restored and non-restored surfaces with teeth wet and then dried. Ten forensic dentists were asked on two separate occasions (one month between each attempt) to indicate whether or not they thought the surface was: a) restored or b) unrestored. Results indicate that forensic dentists detected a significantly higher proportion (p<0.005) of filled surfaces with QLF.