中国28个省/区汉族人群41个STR基因座多态性数据分析

目的调查分析中国28个省/区汉族人群41个STR基因座的遗传多态性,为相关研究和鉴定提供全面科学的基础数据。方法收集28个省/区汉族9 126名无关个体血样本,采用Global FilerTM、AGCU EX-22和AGCU 21+13种试剂盒,进行41个STR基因座分型,统计各基因座等位基因分布和遗传学参数,并对各数据之间进行差异性检验。结果中国28个省/区汉族人群41个基因座分别检出8~76个等位基因,各基因型分布经正和检验,除SE33等7个基因座外,均符合Hardy-Weinberg平衡定律。遗传学参数分析显示,41个基因座中SE33等21个属高鉴别力、高杂合度、高信息量,其余20个属中等高度多态性基因座。部分省份等位基因频率分布数据之间有显著性差异(P0.05),各省与全国综合数据之间则无差异(P0.05)。结论本文调查结果证实41个STR基因座均具有较强的个体识别能力,获得的数据可为法医学应用和筛选适合中国汉族人群基因座等研究和实践提供科学的基础数据。     

15重快速STR复合扩增体系的构建

目的建立一套15重快速STR复合扩增体系。方法选择14个常染色体基因座以及1个性别基因座,采用Fast Start Taq DNA聚合酶系统,以DNA标准品9947A为模板,通过筛选扩增条件、选择热启动酶用量、调整引物平衡、优化快速扩增程序、筛选反应缓冲液、选择反应体系以及筛选添加剂等一系列复合扩增实验,比较各条件下等位基因丢失和非特异性扩增情况。结果在以1 ng DNA为模板、0.4μL聚合酶及10×Fast Start高保真反应缓冲液构成10μL快速体系的条件下,32 min即可获得标准DNA全部15个STR基因座的完整分型,无等位基因丢失和非特异性扩增现象,等位基因均衡性良好。同时,5%甘油、0.01%明胶、0.05%明胶和5 mmol/L硫酸铵可作为PCR扩增过程中拟加入的反应添加剂。结论本研究建立的15重快速STR复合扩增体系可以明显缩短反应时间,提高样品检测效率。     

Soldier,civilian, criminal: identifying pathways to offending of ex-armed forces personnel in prison

Little is known about why some ex-armed forces personnel become involved in the criminal justice system, however, they represent the largest known occupational group in prison. In-depth interviews were employed to explore possible pathways to offending. Twenty ex-armed forces personnel in prison were recruited from five prisons in England. Data were analysed using a combination of thematic analysis and constant comparison methods rooted in grounded theory. Four predominant themes were identified: experiences of trauma and adversity; belonging; impulsivity and creating a soldier. Participants had experienced a number of traumatic incidents and adversity in their lives, encompassing pre, during and post-service but felt a sense of belonging in the armed forces. Participants demonstrated impulsivity in a number of areas with links to both their service in the armed forces and offending behaviour. The creation of the identity of ‘soldier’ was perceived to impact participants’ lives in a number of ways, including their offending, alcohol use and coping with trauma. The interplay of these themes and their potential impact on participants’ pathways to offending are discussed.     

Portrait of the Accused as a Young Man: New Zealand’s Harsh Treatment of Young People who Commit Serious Crimes

Abstract

This article argues that although New Zealand’s unique youth justice system generally considers the whole picture of a young offender and responds holistically to the offending, in the case of those accused of serious crimes, the system draws a limited picture that depicts the young offender as a ‘young adult’. These young people are sentenced in adult courts, where their youth, inexperience and potential for rehabilitation are far less influential than they are in a youth court. The result is harsh treatment of some extremely vulnerable young people, which breaches New Zealand’s international obligations. That harsh treatment is particularly problematic, given its hugely disproportionate effect on Māori youth.     

Evaluation of reliability of STR typing in human colon carcinomas tissues used for identification purpose

The short tandem repeats (STRs) have become an important and widely used tool in forensic casework. Clinical tissue samples are not usually employed in forensic casework, but sometimes, malignant tissue samples may be the only source of biological material for forensic investigations. However, in use of such samples, uncertainties due to microsatellite instability (MSI) and loss of heterozygosity (LOH) may be encountered. In our study of 77 human colon carcinomas tissue with the AmpFlSTR Identifiler Kit comprising 15 STR loci and the amelogenin gene, we detected four kinds of changes between normal tissue and tumor tissue including pLOH, LOH, occurrence of an additional allele (Add) and occurrence of a new allele (New) instead of that found in normal tissue. The overall variation detectable rate was 11.28%, of which pLOH was 79.1%, LOH was 7.9%, Add was 7.9% and New was 5%. Of the above four changes, the incidence rate of pLOH, LOH, Add and New was respectively 8.93%, 0.89%, 0.89% and 0.57%. The STRs mostly affected were D18S51, D5S818, FGA and D19S433. Only pLOH was found at five loci including vWA, TPOX, TH01, D13S317 and amelogenin gene. Our results demonstrate that great care should be taken in the evaluation of typing results obtained from clinical tissue specimens, in particular when no reference samples are available, because genetic instability is a very common event observed in different tumors and the STRs used for individual identification could sometimes be affected.     

Study of Short- and Long-Term Storage of Teeth and Its Influence on DNA

Abstract:  DNA degradation can interfere with the resolution of forensic cases. Allelic dropout often reduces the opportunity for adequate comparisons between degraded and reference samples. This study analyzed DNA degradation in 24 extracted teeth after storage at room temperature for 0, 2, 5, and 10 years. DNA concentration, quantified by dot-blot hybridization, declined significantly for the first 2 years, but there was no significant further degradation from the second to the tenth year of storage. COfiler™ analysis was used and the allelic dropout ratio for the amelogenin locus relative to CSF1PO locus was also estimated. Statistically significant differences were found between fresh teeth and teeth from the 2- and 5-year groups but not from the 10-year group. Under our storage conditions most of the DNA degradation occurred during the first 2 years. Further research is needed to control for individual and external factors that could affect DNA.     

应用常染色体STR基因座共有等位基因数判别全同胞关系

目的建立基于常染色体STR基因座共有等位基因数的全同胞关系判别标准。方法根据280对全同胞及2003对无关个体Identifiler系统15个STR基因座的分型结果,对15个STR基因座的共有等位基因数（S15）和全同胞指数（FSI）进行统计,应用SAS8.2软件包得出Fisher判别函数并与ITO法结果进行比较。结果全同胞对及无关个体对中共有等位基因数目均符合正态分布。采用Identifiler系统15个STR基因座共有等位基因数进行全同胞关系判别时,判别函数分别为：ZFS=3.26970S15-31.51174和ZUI=1.70058S15-8.52411。用上述判别函数进行全同胞/无关个体关系判别时的平均错判率为0.0298。15个STR基因座共有等位基因数法、CODIS13个STR基因座共有等位基因数法与ITO法判别结果差异无统计学意义。结论应用常染色体STR基因座的共有等位基因数判别全同胞关系简便、可信,易于掌握且不受STR基因座等位基因频率的影响。     

6个五核苷酸STR基因座荧光复合扩增体系的建立

目的 构建6个五核苷酸STR基因座荧光复合扩增体系。方法筛选6个多态性程度较高的五核苷酸STR基因座D10S2325、Penta B、Penta W、PentaX、Penta D和PentaE,按照复合扩增引物设计要求,重新设计引物并标记荧光染料,经反复调整和优化,构建6基因座荧光复合扩增体系,并用该复合扩增体系对239名武汉汉族无关个体进行分型。结果6个五核苷酸STR基因座荧光复合扩增体系分型稳定,可重复性好,与各自相应单基因座分型结果完全一致;累积个人识别率达0．999999988,累积非父排除率达0．998063807。结论本文构建的6个五核苷酸STR基因座荧光复合扩增体系具有很高的法医学实用价值,可作为商品化试剂盒的有效补充。     

Developmental Validation of the ANDE 6C System for Rapid DNA Analysis of Forensic Casework and DVI Samples

A developmental validation was performed to demonstrate reliability, reproducibility, and robustness of the ANDE Rapid DNA Identification System for processing of crime scene and disaster victim identification (DVI) samples. A total of 1705 samples were evaluated, including blood, oral epithelial samples from drinking containers, samples on FTA and untreated paper, semen, bone, and soft tissues. This study was conducted to address the FBI’s Quality Assurance Standards on developmental validation and to accumulate data from a sufficient number of unique donors and sample types to meet NDIS submission requirements for acceptance of the ANDE Expert System for casework use. To date, no Expert System has been approved for such samples, but the results of this study demonstrated that the automated Expert System performs similarly to conventional laboratory data analysis. Furthermore, Rapid DNA analysis demonstrated accuracy, precision, resolution, concordance, and reproducibility that were comparable to conventional processing along with appropriate species specificity, limit of detection, performance in the presence of inhibitors. No lane-to-lane or run-to-run contamination was observed, and the system correctly identified the presence of mixtures. Taken together, the ANDE instrument, I-Chip consumable, FlexPlex chemistry (a 27-locus STR assay compatible with all widely used global loci, including the CODIS core 20 loci), and automated Expert System successfully processed and interpreted more than 1200 unique samples with over 99.99% concordant CODIS alleles. This extensive developmental validation data provides support for broad use of the system by agencies and accredited forensic laboratories in single-source suspect-evidence comparisons, local database searches, and DVI.