Automated DNA extraction using the QIAsymphony platform: Estimation of DNA recovery from simulated forensic stains

The aim of this study was to evaluate the forensic protocol recently developed by Qiagen for the QIAsymphony automated DNA extraction platform. Samples containing low amounts of DNA were specifically considered, since they represent the majority of samples processed in our laboratory. The analysis of simulated blood and saliva traces showed that the highest DNA yields were obtained with the maximal elution volume available for the forensic protocol, that is 200 μl. Resulting DNA extracts were too diluted for successful DNA profiling and required a concentration. This additional step is time consuming and potentially increases inversion and contamination risks. The 200 μl DNA extracts were concentrated to 25 μl, and the DNA recovery estimated with real-time PCR as well as with the percentage of SGM Plus alleles detected. Results using our manual protocol, based on the QIAamp DNA mini kit, and the automated protocol were comparable. Further tests will be conducted to determine more precisely DNA recovery, contamination risk and PCR inhibitors removal, once a definitive procedure, allowing the concentration of DNA extracts from low yield samples, will be available for the QIAsymphony.     

Prevalence of mixed DNA profiles in fingernail swabs from autoptic cases

Physical contact between two or more persons can give rise to the transfer of DNA from one person to another and biological material can accumulate under the fingernail hyponichium. The purpose of this study is to value the normal levels of foreign DNA profiles under the fingernail of individuals deceased of a non-violent death, in order to define the usefulness of this approach in the recovery of a suspect's DNA profile. No foreign DNA was found in the majority of the cases.     

A dedicated automated system for extraction, quantification and STR amplification of forensic evidence samples

Forensic DNA analysis is a multi-step process involving extraction of DNA, quantification of human DNA in the extract, amplification using multiplex STR systems, separation of products, and data analysis. The backlog of forensic casework is increasing worldwide. Automation is one significant way to alleviate the bottleneck of sample processing in forensic labs. The HID EVOlution™ Combination System described here is a robust, reliable sample processing platform, easily adapted to forensic laboratory workflows. Using a variety of forensic sample types including: blood stained FTA paper, cotton fabric and denim, dried blood spiked with known PCR inhibitors, saliva on cotton swabs, and semen stains, we found that yields of human DNA and STR profiles obtained with AmpFlSTR^® Idenitfiler^® kits were complete, highly reproducible, and equivalent to results obtained using the manual PrepFiler™ reagent extraction method. Automated operation was clean, and no cross-contamination was detected between extraction blanks and interspersed high DNA content samples.     

A standard procedure for accommodating forensic anthropological and genetic analysis of decomposing human remains from tropical climates

At the Medical Legal Center in Ribeirão Preto, Brazil (CEMEL/FMRP-USP), unidentified decomposing bodies routinely undergo soft tissue removal (by immersion in water at 80–90 °C for 24 h) prior to an anthropological analysis intended to yield a biological profile of age, sex, ancestry, height, pathology and so on. In the event that this analysis is unsuccessful, samples may be submitted for DNA profiling. The tropical climate and the defleshing process may confound preservation, recovery and analysis of DNA, however. In order to establish an optimal standardized protocol for identification of decomposing human remains from a tropical climatic region, the outcome of anthropological and genetic analyses was compared, along with the utility of bone (mainly femur and sternum) and teeth (mainly molar) specimens for DNA analysis. In a sample (n = 39) of partially skeletonized remains, anthropological analysis was sufficient for identification in eight cases. In further six cases, DNA profiling was successfully attempted. As a consequence of our study, we recommend collection of 1–2 well preserved teeth prior to defleshing and anthropological analysis in these circumstances.     

Adaptation and evaluation of the PrepFiler™ DNA extraction technology in an automated forensic DNA analysis process with emphasis on DNA yield, inhibitor removal and contamination security

Within the initial step of the forensic DNA analysis process, the DNA extraction efficiency and especially the removal of potential PCR inhibitors is crucial for subsequent steps, e.g. quantification by real-time PCR and amplification of short tandem repeats (STRs). The protocol of the PrepFiler™ Forensic DNA Extraction Kit was optimized for the application on a Tecan liquid handling workstation Freedom EVO^® 150. This modified application of the PrepFiler™ technology was compared with respect to DNA yield, sensitivity and the ability to remove potential PCR inhibitors to an established routine method working on the same liquid handling workstation based on ChargeSwitch^® Technology (CST) from Invitrogen.     

刑事证明标准之探微

目前,刑事诉讼应达到何种证明程度大致有两种不同的主张,即“客观真实”论和“法律真实”论。在转型这一特定时期,刑事诉讼法修改已提上日程,为此我们应在借鉴两大法系刑事证据制度中的证明标准的基础上正确看待“客观真实”与“法律真实”,构建适合我国司法文化和司法实践的相对合理的具有层次性的刑事证明标准、     

EU GDPR or APEC CBPR? A comparative analysis of the approach of the EU and APEC to cross border data transfers and protection of personal data in the IoT era

This article examines the two major international data transfer schemes in existence today – the European Union (EU) model which at present is effectively the General Data Protection Regulation (GDPR), and the Asia-Pacific Economic Cooperation (APEC) Cross Border Privacy Rules system (CBPR), in the context of the Internet of Things (IoT).While IoT data ostensibly relates to things i.e. products and services, it impacts individuals and their data protection and privacy rights, and raises compliance issues for corporations especially in relation to international data flows. The GDPR regulates the processing of personal data of individuals who are EU data subjects including cross border data transfers. As an EU Regulation, the GDPR applies directly as law to EU member nations. The GDPR also has extensive extraterritorial provisions that apply to processing of personal data outside the EU regardless of place of incorporation and geographical area of operation of the data controller/ processor. There are a number of ways that the GDPR enables lawful international transfer of personal data including schemes that are broadly similar to APEC CBPR.APEC CBPR is the other major regional framework regulating transfer of personal data between APEC member nations. It is essentially a voluntary accountability scheme that initially requires acceptance at country level, followed by independent certification by an accountability agent of the organization wishing to join the scheme. APEC CBPR is viewed by many in the United States of America (US) as preferable to the EU approach because CBPR is considered more conducive to business than its counterpart schemes under the GDPR, and therefore is regarded as the scheme most likely to prevail.While there are broad areas of similarity between the EU and APEC approaches to data protection in the context of cross border data transfer, there are also substantial differences. This paper considers the similarities and major differences, and the overall suitability of the two models for the era of the Internet of Things (IoT) in which large amounts of personal data are processed on an on-going basis from connected devices around the world. This is the first time the APEC and GDPR cross-border data schemes have been compared in this way. The paper concludes with the author expressing a view as to which scheme is likely to set the global standard.     

论监察案件的证据标准——以刑事诉讼证据为参照

监察证据无需转化便可直接获得刑事诉讼证据资格,但作为职务犯罪定案的根据,必须具备刑事诉讼证据的形式条件和实质条件。监察机关的调查权与刑事侦查权具有相同的性质和功能,监察机关调查取证虽然不直接适用刑事诉讼法,但必须参照刑事诉讼法的侦查取证规则。为保障调查取证的合法性,应当对调查活动进行合理规制,对于非法获取的证据应当按照刑事诉讼法及相关司法解释确定的非法证据排除规则予以排除。监察机关调查终结的案件,应当达到刑事侦查终结的证明标准,应当低于法院判决有罪的标准,但不能比其他普通刑事案件的证明标准更高。     

A review of quality procedures in the UK forensic sciences: What can the field of digital forensics learn?

With a reliance on the various forms of forensic science evidence in complex criminal investigations, the measures for ensuring its quality are facing increasing scrutiny. Improvements to quality management systems, to ensure both the robust application of scientific principles and the accurate interpretation and reporting of results, have arisen as a consequence of high-profile rebuttals of forensic science evidence, combined with process improvements driven by evaluation of current practice. These improvements are crucial to ensure validity of results as well as providing assurance for all those involved in the Criminal Justice System. This work first examines the quality management systems utilised for the examination and analysis of fingerprint, body fluid and DNA evidence. It then proceeds to highlight an apparent lack of comparable quality assurance mechanisms within the field of digital forensics, one of the newest branches of forensic science. Proposals are provided for the improvement of quality assurance for the digital forensics arena, drawing on the experiences of, and more well-established practices within, other forensic disciplines.     

Intra‐ and Inter‐Element Variability in Mitochondrial and Nuclear DNA from Fresh and Environmentally Exposed Skeletal Remains,

Successful identification of skeletonized remains often relies upon DNA analyses, frequently focusing on the mid‐diaphysis of weight‐bearing long bones. This study explored intra‐bone DNA variability using bovine and porcine femora, along with calcanei and tali. DNA from fresh and short‐term environmentally exposed bone was extracted utilizing demineralization and standard lysis buffer protocols, and DNA quantity and quality were measured. Overall, femoral epiphyses, metaphyses, and the tarsals had more nuclear and mitochondrial DNA than did the femoral diaphyses. DNA loss was much more rapid in buried bones than in surface exposed bones, while DNA quality differed based on environment, but not bone region/element. The demineralization protocol generated more DNA in some bone regions, while the standard lysis was more effective in others, and neither significantly affected DNA quality. Taken together, these findings reinforce the importance of considering inter‐ and intra‐bone heterogeneity when sampling skeletal material for forensic DNA‐based identifications.