The use of the M-Vac® wet-vacuum system as a method for DNA recovery

Collecting sufficient template DNA from a crime scene sample is often challenging, especially with low quantity samples such as touch DNA (tDNA). Traditional DNA collection methods such as double swabbing have limitations, in particular when used on certain substrates which can be found at crime scenes, thus a better collection method is advantageous. Here, the effectiveness of the M-Vac® Wet-Vacuum System is evaluated as a method for DNA recovery on tiles and bricks. It was found that the M-Vac® recovered 75% more DNA than double swabbing on bricks. However, double swabbing collected significantly more DNA than the M-Vac® on tiles. Additionally, it was found that cell-free DNA is lost in the filtration step of M-Vac® collection. In terms of peak height and number of true alleles detected, no significant difference was found between the DNA profiles obtained through M-Vac® collection versus double swabbing of tDNA depositions from 12 volunteers on bricks. The results demonstrate that the M-Vac® has potential for DNA collection from porous surfaces such as bricks, but that alterations to the filter apparatus would be beneficial to increase the amount of genetic material collected for subsequent DNA profiling. These results are anticipated to be a starting point to validate the M-Vac® as a DNA collection device, providing an alternative method when DNA is present on a difficult substrate, or if traditional DNA collection methods have failed.     

The effect of NucleoSpin® Forensic Filters on DNA recovery from trace DNA swabs

Forensic DNA profiling is a globally accepted method for human identification, however, obtaining full DNA profiles from trace DNA can be challenging. The optimal recovery of DNA from trace DNA swabs is therefore crucial. Methods for extracting DNA from swabs often make use of a spin basket combined with a centrifugation step, to enhance the release of cells from the swab prior to DNA extraction. The NucleoSpin® Forensic Filter (Macherey-Nagel, Düren) is a type of spin basket, but it has not been thoroughly assessed on trace DNA samples. This study aimed to assess if the inclusion of the NucleoSpin® Forensic Filter significantly improved DNA recovery and DNA profiling success from cotton and flocked swabs used to collect trace DNA and buccal cells (control). Buccal cells and trace DNA samples were collected from 25 volunteers using each swab type (cotton and flocked) in duplicate. DNA was extracted from the samples using the NucleoSpin® DNA Forensic kit, one set with, and the other set without, NucleoSpin® Forensic Filters. DNA concentration was assessed using real time PCR, and DNA profiling was done using the PowerPlex® ESX 16 system. The inclusion of the NucleoSpin® Forensic Filters significantly improved DNA concentration for buccal cells that were collected using flocked swabs (p = 0.035). However, no significant differences were noted for trace DNA samples for either swab type. There was also no significant difference in DNA profiling success when NucleoSpin® Forensic Filters were used, regardless of swab and sample type. These results may be helpful for laboratories that are considering the NucleoSpin® Forensic Filters in the DNA extraction workflow, particularly for trace DNA samples.     

The effect of cleaning agents on the ability to obtain DNA profiles using the Identifiler™ and PowerPlex® Y multiplex kits

Abstract: A year after the introduction of Identifiler? into the forensic DNA laboratories of the Institute of Environmental Science and Research Limited (ESR), increasing occurrences of dropout of the three loci, D7S820, D18S51, and FGA, were observed in samples where the DNA was not degraded and sufficient DNA was present that full DNA profiles were to be expected. The dropout was either partial or complete at these loci. Full profiles could sometimes be obtained by reamplification of samples using the same input amount of DNA. After a thorough investigation of the methods and procedures used in the laboratory, the cause of this inhibition was identified as the cleaning agent TriGene? ADVANCE. This was determined after the deliberate addition of varying amounts of different cleaning reagents into the DNA amplification reactions. At concentrations of 0.004% TriGene? ADVANCE caused inhibition resulting in tri‐loci dropout. At concentrations of 0.04% and higher, complete inhibition was observed. An effect was also seen on the amplification of samples using the Y STR profiling system PowerPlex^®Y. This work highlights the importance of checking all reagents and chemicals prior to use, even those with no apparent direct influence on the DNA profiling process.     

Assessing the performance of quantity and quality metrics using the QIAGEN Investigator® Quantiplex® pro RGQ kit

The Quantiplex® Pro RGQ kit quantifies DNA in a sample, supports the detection of mixtures and assesses the extent of DNA degradation based on relative ratios of amplified autosomal and male markers. Data show no significant difference in the accuracy and sensitivity of quantification between this and the Promega PowerQuant® System, both detecting the lowest amount of DNA tested, 4 pg. Laboratory controlled mixed male:female DNA samples together with mock sexual assault samples were quantified across a range of mixture ratios. Analysis software detected mixed DNA samples across all ratios for both quantification kits. Subsequent STR analysis using the Investigator® 24Plex QS Kit was able to corroborate mixture detection down to 1:25 male:female DNA ratios, past which point mixtures appeared identical to single-source female samples. Analysis software also detected laboratory degraded DNA samples, with data showing a positive trend between the Degradation Index (DI) and length of time of sonication. When used on ancient remains the assay was able to triage samples for further analysis, and STR profiles were concordant with DNA quantification results in all instances. STR analyses of laboratory-controlled sensitivity, mixture, and degradation studies supports the quality metric obtained from quantification. These data support the use of the Quantiplex® Pro RGQ kit for sample screening and quantification in forensic casework and ancient DNA studies.     

利用EZ—tape提取DNA破案1例

1案件简介 某年5月某日，某郊区发现一具无名男尸，经勘验系他杀。死者穿着符合流浪拾荒人员，死者全身无开放性损伤，背、臀部有多处木棒类钝器伤，现场未发现有价值的物证线索。经排查，发现现场附近看护房看管员张某有重大嫌疑，从看护房内提取断裂杨树木棍一根。     

Detection and analysis of DNA mixtures with the MiSeq FGx®

Recognizing and interpreting mixtures are challenges that occur frequently in forensic casework. Therefore, any new analysis methods that are implemented must handle the challenges of mixed forensic samples. Next generation sequencing offers advantages over capillary electrophoresis in amplicon multiplexing and degraded sample analysis; however, advantages with mixed samples rely heavily on the advancement of user-friendly analysis software. This research analyzed samples with the ForenSeq™ DNA Signature Prep Kit on the MiSeq FGx® and compared them with the GlobalFiler™ STR Kit for capillary electrophoresis. Metrics tested for both chemistries included concordance, limits of detection, and mixture analysis. Data analysis for mixture samples was completed with the MixtureAce™ plug-in and ArmedXpert™ software. Next generation sequencing offered distinct advantages in limits of detection and isoallele heterozygosity but suffered from increased variability in stutter and allele count ratios compared to capillary electrophoresis.     

The neuroendocrine effects of the TASER X26®: A brief report

IntroductionLaw enforcement officers use conducted electrical weapons (CEW) such as the TASER X26^® to control violently resistive subjects. There are no studies in the medical literature examining the effects of these weapons on the human stress response. This is the first study to compare the human stress response to conducted electrical weapons, oleoresin capsicum (O.C.), a cold-water tank immersion, and a defensive tactics drill.MethodsSubjects were randomized to one of the four interventions studied. Subjects received either a 5-s exposure from the TASER X26 CEW with the probes fired into the back from 7 ft, a 5-s spray of O.C., a skin and mucous membrane irritant, to the eyes, a 45-s exposure of the hand and forearm in a 0 °C cold water tank, or a 1-min defensive tactics drill.ResultsAlpha-amylase had the greatest increase from baseline at 10–15 min with the defensive tactics drill. Cortisol had the greatest increase at 15–20 min with O.C. Cortisol remained most elevated at 40–60 min in the defensive tactics drill group.ConclusionsOur preliminary data suggests that physical exertion during custodial arrest may be most activating of the human stress response, particularly the sympathetic–adrenal–medulla axis. This may suggest that techniques to limit the duration of this exertion may be the safest means to apprehend subjects, particularly those at high-risk for in-custody death. Conducted electrical weapons were not more activating of the human stress response than other uses of force.     

The use of telepsychiatry within forensic practice: a literature review on the use of videolink – a ten-year follow-up

In the last decade, telepsychiatry – the use of telecommunications technologies to deliver psychiatric services from a distance – has been increasingly utilised in many areas of mental health care. Since the review by Khalifa and colleagues in 2007 the body of literature relevant to the forensic applications of telepsychiatry has grown substantially, albeit not by much in the United Kingdom. In the current review, we aim to provide an update summary of the literature published since 2007 to determine the effectiveness and feasibility of increasing telepsychiatry utilisation in forensic practice. The literature reviewed provides some encouraging evidence that telepsychiatry is a reliable, effective and highly acceptable method for delivering mental health care in forensic settings. There are also a number of papers that indicate the use of telepsychiatry may be cost effective for health providers in the longer term. Further research is required to consider the potential legal and ethical implications of using telepsychiatry in forensic settings.     

应用EZ1自动提取仪提取关节软骨组织的DNA

在刑事案件的DNA检验中.对于一些腐败的生物检材.多采用骨骼组织中的骨松质或骨密质来进行DNA检验.这主要是因为骨骼有外部硬组织的保护,能够抵抗外界环境的影响,其中的DNA不易被破坏[1].     

Assessment of the Yfiler® Plus PCR amplification kit for the detection of male DNA in semen-negative sexual assault cases

The ability to detect male epithelial cells deposited during digital penetration or penile penetration without ejaculation is limited by the sensitivity of the Y-STR profiling kit. In this study, the relative profiling success of the Thermofisher Yfiler® Plus kit was compared to its predecessor, AmpFlSTR Yfiler®, for 104 semen-negative sexual assault samples from casework at Forensic Science SA, Adelaide, South Australia. Yfiler Plus generated allele information in 25% more samples than Yfiler and gave a higher recovery of informative alleles in all but two samples where detectable male DNA was present. Where a profile was obtained in both kits, 92% of samples gave a higher percentage of informative loci with Yfiler Plus compared to Yfiler. Yfiler Plus also resolved DNA mixtures in 15 samples as compared to 1 sample with Yfiler. Detection of male DNA with the Quantifiler™ Trio DNA Quantification kit was shown to correlate with a successful profiling outcome with Yfiler Plus. The success of profiling with Yfiler Plus was independent of the time elapsed between the alleged offence and the sample being collected, the type of sexual penetration which occurred, and the anatomical origin of the sample.     

Characterisation of forward stutter in the AmpFlSTR® SGM Plus® PCR

PCR amplification of tetrameric short tandem repeats (STRs) can lead to Taq enzyme slippage and artefact products typically one repeat unit less in size than the parent STR. These back stutter or n ? 4 amplification products are low-level relative to the amplification of the parent STR but are widely seen in the forensic community where tetrameric STRs are employed in the generation of DNA profiles. To aid the interpretation of DNA mixtures where minor contributor(s) might be present in comparable amounts to the back stutter products, the typical amounts of back stutter generated have been well characterised and guidelines for interpretation are in place. However, further artefacts thought to be Taq enzyme slippage leading to products with one repeat unit greater than the parent sequence (n + 4 or forward stutter) or two repeats less (n ? 8 or double back stutter) also occur, but these have not been well characterised despite their potential influence in mixture interpretations. Here we present findings with respect to these additional artefacts from a study of 10,000 alleles and include guidelines for interpretation.     

The crime of the century? The case for the Holocaust

With the twentieth century now ended the Holocaust is surelya leading contender for the title of ``The Crime of the Century.'Although a massive literature exists on the Holocaust, very littleof this literature has been produced by criminologists. Somereasons for this relative neglect are identified and a case ismade for the claim that criminology can contribute to anunderstanding of the Holocaust and that the Holocaust cancontribute to the development of a more profound criminology. Thispaper draws upon an integrative criminological approach toconstruct a framework for understanding the Holocaust. This multi-disciplinary framework links philosophical, sociolegal,sociological, behavioral and criminological dimensions todiscriminate between unique and non-unique aspects of the Holocaustas a case of genocide and as crime. The paper closes with someobservations on the relevance of the Holocaust for challengesconfronting a twenty-first century criminology.     

Internal validation study of the PowerPlex® Y23 system

The PowerPlex Y23 System is a 23-loci, 5-color Y-STR multiplex designed for genotyping forensic casework samples, database samples and paternity samples. The kit contains: all 12 loci in the current PowerPlex Y System, the additional 5 loci found in AmpFlSTR Y-filer, plus 6 new loci. An internal validation study of the PowerPlex Y23 kit was therefore conducted including the following aspects: sensitivity, mixture studies of male–male and female–male DNA, performance with simulated inhibition and stutter calculations. 100 Caucasians living in Switzerland were also typed using the PowerPlex Y23 kit.     

The End of the Beginning? The Freedom of Information Bill 1999

With the publication of its plans for a Bill on Freedom of Information, the new Labour government has been accused of abandoning its promise of greater openness in the way government is conducted in this country and its proposals are seen as a departure from the highly applauded contents of the White Paper published in December 1997. The draft Bill has been pilloried by friend and foe alike. It is seen as a litmus test of Blair's government and where it really stands on the citizen/state relationship and how the future balance will lie between the executive and Parliament. The authors examine the events surrounding the publication of the Bill and its scrutiny by the pre-legislative select committees in the Commons and Lords. The Home Secretary has hinted at possible concessions in the light of fierce criticism. Is this a Bill worth saving and how can it be improved to capture a more appropriate balance between confidentiality, secrecy, and openness in the conduct of modern governance?     

Examples of kinship analysis where Profiler Plus™ was not discriminatory enough for the identification of victims using DNA identification

The identification of the victims of the 2009 Victorian bushfires disaster, as in other mass disasters, relied on a number of scientific disciplines - including DNA analysis. As part of the DVI response, DNA analysis was performed to assist in the identification of victims through kinship (familial matching to relatives) or direct (self source of sample) matching of DNA profiles. The majority of the DNA identifications made (82%) were achieved through kinship matching of familial reference samples to post mortem (PM) samples obtained from the victims. Although each location affected by the bushfires could be treated as a mini-disaster (having a small closed-set of victims), with many such sites spread over vast areas, DNA analysis requires that the short tandem repeat (STR) system used be able to afford enough discrimination between all the DVI cases to assign a match. This publication highlights that although a 9-loci multiplex was sufficient for a DVI of this nature, there were instances that brought to light the short comings of using a 9-loci multiplex for kinship matching--particularly where multiple family members are victims. Moreso it serves to reinforce the recommendation that a minimum of 12 autosomal STR markers (plus Amelogenin) be used for DNA identification of victims which relies heavily on kinship matching.     

DNA typing from skeletal remains using GlobalFiler™ PCR amplification and Investigator® 24plex QS kits

Since the beginning of our work in 2003 our laboratory has focused exclusively on STR DNA from bone, a powerful tool in missing person cases. In cases such as mass disasters or missing persons, human remains are challenging to identify as they may be fragmented, burnt, recovered from water, degraded, and/or contain inhibitory substances. To address these challenges, this study has evaluated the performance of relatively new STR kits Investigator® 24plex QS kit (Qiagen) and GlobalFiler™ PCR Amplification kit (Thermo Fisher Scientific) by comparing it with current uses of the AmpFLSTR® Identifiler® Plus kit (Applied Biosystems) to obtain genetic information from skeletal remains. We analyzed 20 bone samples of skeletal remains from routine casework submitted for body identifications by law enforcement corresponding using Investigator® 24plex QS kit and GlobalFiler™ PCR Amplification kit, previously analysed AmpFLSTR® Identifiler® Plus kit (Thermo Fisher Scientific). The data indicates that the STR profiles obtained using the GlobalFiler™ and Investigator® 24plex QS kit for analysis of skeletal remains has shown results in an increased number of reportable genetic loci, and provide greater power of discrimination in comparison to the Identifiler® Plus Kit. Advanced extraction and purification techniques, together with more sensitive and robust new amplification kits allowed us to overcome the challenges associated with processing compromised skeletal remains and ultimately obtain full STR DNA profiles in 99% of the bones.     

Banking in the cloud: Part 1 – banks' use of cloud services

This paper looks at EU banks' use of public cloud computing services. It is based primarily on anonymised interviews with banks, cloud providers, advisers, and financial services regulators. The findings are presented in three parts. Part 1 explores the extent to which banks operating in the EU, including global banks, use public cloud computing services. It describes how banks are using cloud computing and the key drivers for doing so (such as time to market), as well as real and perceived barriers (such as misconceptions about cloud and financial services regulation), including cultural and technical/commercial aspects. It summarises how banks have approached the cloud and how cloud providers have approached the banking sector.Part 2 of this paper will cover the main legal and regulatory issues that may affect banks' use of cloud services, including how the regulation of outsourcing applies to banks' use of cloud services. Part 3 will look at the key contractual issues that arise between banks and cloud service providers, including data protection requirements, termination, service changes, and liability.All three parts of the paper can be accessed via Computer Law and Security Review's page on ScienceDirect at: http://www.sciencedirect.com/science/journal/02673649?sdc=2. The full list of sources is available via the same link and will be printed alongside the third part of the paper.     

Comparison of the M-Vac® Wet-Vacuum-Based Collection Method to a Wet-Swabbing Method for DNA Recovery on Diluted Bloodstained Substrates*†‡

A wet-vacuum-based collection method with the M-Vac^® was compared to a wet-swabbing collection method by examining the recovery of diluted blood on 22 substrates of varying porosity. The wet-vacuum method yielded more total nuclear DNA than wet-swabbing on 18 porous substrates, recovering on average 12 times more DNA. However, both methods yielded comparable amounts of total DNA on two porous and two nonporous substrates. In no instance did wet-swabbing significantly recover more DNA. The wet-vacuum method also successfully collected additional DNA on previously swabbed substrates. Mitochondrial DNA yields were assessed, and outcomes were generally similar to the nuclear DNA outcomes described above. Results demonstrate that wet-vacuuming may serve as an alternative collection method to swabbing on difficult porous substrates and could potentially recover additional DNA on previously swabbed substrates. However, swabbing remains the preferred collection method on substrates with visible stains and/or nonporous surfaces for reasons of convenience, simplicity, and lower cost relative to the wet-vacuum method.