妇科肿瘤和乳腺癌组织常染色体和X染色体STR的突变分析

目的探讨妇科肿瘤组织和乳腺癌组织的法医学常用STR基因座突变类型和规律,以及显微切割技术在肿瘤组织法医学鉴定中的应用。方法应用Power Plex 21 System和Argus X-12试剂盒对62例乳腺癌患者,62例妇科恶性肿瘤患者,10例良性妇科肿瘤患者外周血、肿瘤组织和癌旁组织DNA样本进行复合扩增,获得STR分型,并选取存在突变的部分肿瘤组织进行显微切割。结果妇科恶性肿瘤患者外周血的STR分型与癌旁组织一致;46.77%的妇科恶性肿瘤组织中观察到4种STR突变类型,显著高于良性肿瘤的STR突变率(P0.01)和乳腺癌的STR突变率(P=0.009)。显微切割获得的间质细胞的STR分型与癌旁组织一致。结论本研究所检测的STR基因座在妇科恶性肿瘤组织中的稳定性较差,不适用于该系统肿瘤组织的法医学鉴定;显微切割技术可准确分离间质细胞,能够代表肿瘤来源个体的正常DNA分型,是解决此类案件法医学鉴定的一种有效方法。     

北京汉族21个STR基因座的群体遗传学调查与法医应用评价

目的调查459例北京汉族无关个体21个常染色体非CODIS的STR基因座遗传多态性并评价其应用价值。方法用AGCU21＋1荧光标记复合扩增系统对459例无关个体的21个STR基因座（D6S474、D12SATA63、D22S1045、D10S1248、D1S1677、D11S4463、D1S1627、D3S4529、D2S441、D6S1017、D4S2408、D19S433、D17S1301、D1GATA113、D18S853、D20S482、D14S1434、D9S1122、D2S1776、D10S1435、D5S2500）进行检验。得到STR分型后,用相关软件进行统计分析并计算法医学应用参数。结果获得21个STR基因座的频率分布;相关参数为：H值从0.5894-0.8038,PD值从0.7898-0.9265,PE3值从0.3618-0.6029,PE2值从0.2031-0.4256,PIC值从0.5638到0.7640。结论联合应用Identifiler系统和AGCU21＋1系统,有利于亲子关系的认定及对可疑突变的判断。     

云南苗族常染色体STR遗传多态性及其遗传结构分析

目的研究云南苗族常染色体9个STR基因座遗传多态性并分析其遗传结构。方法采用荧光标记PCR复合扩增、基因扫描自动分型技术调查了87名云南苗族无关健康个体9个STR基因座等位基因分布情况。结果9个基因座共检出52种等位基因和109种基因型,等位基因频率分布在O．0057～0．7184。经计算杂合度（H）为0．4023-0．8161、多态信息量（PIC）为0．4090～0．8057、个体识别力（DP）为0．6429。0．9436、非父排除率（PE）为0．1153～0．5654。X^2检验显示所有基因座均符合Hardy—Weinberg平衡。聚类分析结果显示．苗族、僳僳族、傣族、德昂族、普米族及景颇族遗传关系较近。结论为进一步研究STR遗传结构奠定了基础．在人类学、法医学等领域也有重要的应用价值。     

Uses of the NIST 26plex STR assay for human identity testing

Ongoing work at the U.S. National Institute of Standards and Technology has focused on the characterization of 26 autosomal STR loci for human identity testing. These 26 loci are in addition to the existing 13 U.S. core loci and those found in PowerPlex16 and Identifiler commercial STR typing kits. The amplification of the 26 loci has been optimized for degraded extracts in unique miniplex panels and also for reference samples as a single reaction 26plex assay. A study has been performed comparing genotypes obtained with the 26plex primers to those with miniplex panels for allele drop out and concordance. The forensic utility of the 26plex assay was evaluated for situations where additional loci are beneficial. The utility of this large multiplex was also tested in a case involving DNA extracted from degraded bone samples. The 26plex can serve as a low-cost assay (compared to commercially available kits) useful for both sorting comingled remains and providing additional markers for increased statistical support for samples that require “non-trio” family references for human identification.     

Identification of gestational trophoblastic disease in a sexual assault case

In this study, gestational trophoblastic disease (GTD) was observed by short tandem repeat (STR) typing from the aborted tissues in a sexual assault case. By histological screening, the fetal tissue could not be distinguished from the maternal tissue in this case. Therefore, five specimens were collected randomly from the aborted tissues for DNA analysis. STR typing was performed by the commercial ABI Identifiler kit. The results showed that three specimens were of the maternal origin, one was a mixture of the mother and male fetus, and the other one was of male fetal origin with partial triploid. Three alleles were identified in each locus of D8S1179, D7S820 and VWA for the fetal specimen. For these three alleles, one matched the maternal origin and the others matched the putative paternal origin (suspect). Analysis of the Y-STR by using the commercial ABI Y-Filer kit, the fetal types matched the types of the suspect. We reported the case of partial mole on forensic evidence and gave the valuable information from its identification.     

Combined Statistical Analyses of Forensic Evidence in Sexual Assault: A Case Report and Brief Review of the Literature

DNA analysis has been widely used in the forensic field in order to contribute to identifying the perpetrator of a crime. Forensic investigation in sexual assaults usually focuses on locating and identifying biological fluids, followed by DNA analysis. The identification of certain compounds present in condoms can be useful to reconstruct the occurred event, especially in cases of sexual assaults where the DNA analysis did not show the presence of a male profile and where RNA analysis did not show the presence of sperm markers. Herein we describe the case of a woman reporting to be victim of sexual assault, who was not able to provide accurate information concerning the dynamics of the event; she remembered only forced penile–vaginal penetration by a single perpetrator. We performed short tandem repeat (STR) analyses and mRNA typing for forensic genetics testing on vaginal and rectal swabs collected on the victim, and Fourier-transform infrared spectroscopy (FTIR) followed by chromatographic analyses for the detection of condom compounds on the same swabs. The STR analysis showed only the victim’s genetic profile, and RNA analysis showed only the presence of vaginal and skin markers. In this situation, the identification of condom compounds residues on vaginal swabs became important as it complemented other collected evidences allowing the Court to reconstruct the events. A proposal of likelihood ratio (LR) calculation for the assessment of the weight of evidence in this case is described.     

引物结合区点突变致D18S51等位基因丢失

目的确定D18S51基因座是否存在等位基因缺失及其原因。方法应用多个STR试剂盒检测检材以确定D18S51基因座的等位基因缺失情况;重新设计引物对所测D18S51基因座进行单独扩增,并对缺失的等位基因进行测序。结果该案例被检个体的D18S51侧翼序列引物结合区发生突变,致等位基因丢失。结论亲权鉴定时出现不符合孟德尔遗传规律现象,应使用多个试剂盒检测验证以避免父权误判。     

Forensic examination and application of areca nuts as material evidence

In this study, we aimed to explore the possibility of DNA analysis of areca nut as material evidence and the value of short tandem repeat (STR) typing of areca nut as material evidence under the condition of simulating external environment. In this study, water soaking, soil burial, sun exposure, and wet environment were used to treat areca nut residues. Chelex 100 was used to extract DNA, the PowerPlex21 kit to amplify, and the ABI PRISM^® 310 Genetic Analyzer to analyze the DNA of areca nut residues. DNA and STR typing were performed to analyze the residue after chewing. The results showed that the number of residual sites decreased with time under the conditions of water soaking, soil burial, sun exposure, and wet environment. Thus, areca nut can be used as forensic material evidence for DNA analysis and individual identification.     

STRAND: A Cloud expert system for non-human DNA analysis

The aim of this paper is to present the STRAND (STR ANimal Database) cloud expert system for non-human DNA analysis. The cloud expert system (CES) combines the cross-referenced registries of STR markers for different species and a DNA database for comparison of DNA profiles, with a repository of scientific papers and a dashboard for unpublished data, protocols, negative results and announcements related to animal DNA typing.