全基因组扩增技术的法医学应用价值及其结果评价

微量模板DNA的分析,一直是法医学特别关注和急需解决的难题之一,近年发展起来的一系列技术为解决这一问题提供了新的可能途径,本文即对微量模板DNA分析技术的进展和目前逐步发展的全基因组扩增技术的法医学应用价值、结果评价进行浅议。     

To act or not to act, that is the question: informed consent in a criminal perspective

Some years ago the doctor was seen as the one who "knows better", and it was absolutely unconceivable that the patient could refuse the suggested treatment or even ask any questions about it. Differently, nowadays doctors face demands to keep their patients informed and can even be sued when they act without patient knowledge and consent. On the patient's side this new paradigm does not necessarily legitimate euthanasia--still criminally forbidden in most parts of the world--but allows some kind of personal power over body, health and life, materialized in advance directives. On the doctor's side, it entails a change in the list of good medical practices, imposing the doctrine of informed consent and the prohibition of dysthanasia.     

Assessing the publication output in the field of forensic science and legal medicine using Web of Science database from 2011 to 2020

The aim of this study was threefold. First, it analyzed the characteristics of the publication outputs for the Legal Medicine (LM) category using the Web of Science (WoS) database during 2011–2020. Second, it discussed the distribution of the papers for the 25 most productive countries/regions in terms of quality and quantity, such as the h-index and GDP per capita. Finally, it investigated the trend and temporal stability of the journal impact factor (JIF) and determined the percentage of the journal self-citations. The findings suggested that the number of papers, the average number of pages of the papers, the average number of cited references in the papers, the average number of authors per paper, the percentage of open access papers, as well as international and domestic collaboration tended to increase regularly. However, the productivity was limited when compared to the whole WoS database, since there was no significant change in the number of the journals. The countries/regions with the highest number of publications were not those that made the most impact in terms of the widespread impact of the publications. The level of international cooperation and the funding for the research had dramatic impact on the visibility of papers. The average JIF has increased significantly while the journal self-citation rates have decreased in a similar way. The journals have had very stable (have not fluctuated) impact factors over time. During the period studied, the journals with the higher impact factors (Q1, Q2) published many more papers than journals with the lower impact factors (Q3, Q4).     

Human genomic DNA quantitation system, H-Quant: development and validation for use in forensic casework

The human DNA quantification (H-Quant) system, developed for use in human identification, enables quantitation of human genomic DNA in biological samples. The assay is based on real-time amplification of AluYb8 insertions in hominoid primates. The relatively high copy number of subfamily-specific Alu repeats in the human genome enables quantification of very small amounts of human DNA. The oligonucleotide primers present in H-Quant are specific for human DNA and closely related great apes. During the real-time PCR, the SYBR Green I dye binds to the DNA that is synthesized by the human-specific AluYb8 oligonucleotide primers. The fluorescence of the bound SYBR Green I dye is measured at the end of each PCR cycle. The cycle at which the fluorescence crosses the chosen threshold correlates to the quantity of amplifiable DNA in that sample. The minimal sensitivity of the H-Quant system is 7.6 pg/microL of human DNA. The amplicon generated in the H-Quant assay is 216 bp, which is within the same range of the common amplifiable short tandem repeat (STR) amplicons. This size amplicon enables quantitation of amplifiable DNA as opposed to a quantitation of degraded or nonamplifiable DNA of smaller sizes. Development and validation studies were performed on the 7500 real-time PCR system following the Quality Assurance Standards for Forensic DNA Testing Laboratories.     

From crime scene to courtroom: A review of the current bioanalytical evidence workflows used in rape and sexual assault investigations in the United Kingdom

Sexual assault casework requires the collaboration of multiple agency staff to formalise an investigative pipeline running from crime scene to court. While the same could be said of many other forensic investigations, few require the additional support of health care staff and the combined forensic involvement of body-fluid examiners, DNA experts and analytical chemists. The sheer amount of collaborative effort between agencies is laid out through a detailed examination of the investigative workflow from crime scene to courtroom with each step in the pipelines detailed and discussed. Beginning with a review of sexual assault legislation in the United Kingdom this article details how sexual assault investigations are initiated by police and supported by sexual assault referral centre (SARC) staff who are often the first responders providing primary healthcare and patient support to victims while simultaneously collecting and assessing forensic evidence. Detailing the myriad of evidential material that can be documented and collected at the SARC, the review identifies and categorises key forensic tests to first detect and identify body-fluids recovered from evidence through to the secondary analysis of DNA to help identify the suspect. This review also focusses on the collection and analysis of biological material used to support the allegation that the sexual activity was non-consensual and provides a breakdown of common marks and trauma as well as a review of common analytical methods used to infer Drug Facilitated Sexual Assault (DFSA). The culmination of the investigative pipeline is discussed by reviewing the Rape and Serious Sexual Assault (RASSO) workflow used by the Crown Prosecution Service before providing our thoughts on the future of forensic analysis and possible changes to the described workflows.     

Alcohol and Parasomnias: The Statistical Evaluation of the Parasomnia Defense in Sexual Assault,Where Alcohol is Involved

Sleep sex may be a defense for alleged sexual assault. The International Classification of Sleep Disorders (ICSD3) states: “Disorders of arousal should not be diagnosed in the presence of alcohol intoxication… The former [alcohol blackouts] are exponentially more prevalent.” A panel member of ICSD3, quoting ICSD3 asserts: “alcohol intoxication should rule out a sleep-walking defense”. This implies extremely strong support for a prosecution hypothesis (H_p) over a defense hypothesis (H_d). I use Bayesian methodology to evaluate the evidential probity of alcohol intoxication. The likelihood ratio, LR, measures the amplification of prior odds of guilt, . By Bayes' theorem, . I use data from cross-sectional studies of sexual assault and prevalence of alcohol use, in college students, with data from longitudinal studies, and data from the epidemiology of parasomnias to evaluate LR (alcohol). LR ~1.5 or 5, depending whether alcohol does, or does not, increase the risk of parasomnias. The proposition of extremely strong support for H_p implies a LR ~1,000,000, so the proposition in ICSD3 is not supported by formal analysis. The statistical reasoning in ICSD3 is unclear. There appears to be inversion of the Bayesian conditional (confusing intoxication given assault, and assault given intoxication) and failure to evaluate alcohol intoxication in H_d. Similar statistical errors in R. v Sally Clark are discussed. The American Academy of Sleep Medicine should review the statistical methodology in ICSD3.