两种DNA提取方法检测微量陈旧汗斑1例

与人体接触过的衣、物常常附有体表脱落的上皮细胞成分。有试验证明,人体只要接触物体5秒钟以上,即有可能细胞遗留在物体上,也就是说,有可能留下核DNA及线粒体DNA[1]。在刑事案件中,如能成功地对有关物品上粘附的脱落上皮细胞的DNA检验,便可为案件的侦查和审判提供重要的线索和证据[2]。作者在实际检案中遇到一例微量陈旧汗斑,通过联合应用两种DNA的提取方法并进行了对比,解决了该案的难题。报道如下:1简要案情2003年初,某女被杀害。现场提取男士夹克衫一件,领后部有可疑油渍样斑迹,考虑此处有穿衣者留下的汗斑。2检验2.1检验材料犯罪…     

引物3'端第二个碱基SNP变异的长度多态性遗传标记检测

目的为了获得引物3'端存在SNP点突变的插入缺失遗传标记rs10644346所有等位基因片段。方法基于等位基因特异性PCR原理,设计一条共用上游引物,二条3’端倒数第二个位置特异性碱基的下游引物。运用该三条引物检测150个无关个体及10例亲子关系已确定的三联体,同时运用其中二条引物(共同上游引物和其中一条下游引物)扩增9例样本。结果三条引物扩增150个无关个体均有清晰扩增片段;10例三联体案例亲代与子代扩增片段均符合孟德尔遗传定律;二条引物扩增9例样本后发现特定片段丢失。结论本次研究设计的三条引物PCR,证明特异性碱基位置除了通常的3'末端,理想条件下3'端的其他位置(如倒数第二个位置)也可以成为有效选择,该三条引物设计方法为检测引物侧翼存在点突变的遗传标记提供了一种新的参考。     

非领导职务公务员考核量化管理模型构建及实现路径

目前,非领导职务公务员考核存在定性多、定量少,主观因素多、客观标准少等突出问题,缺乏一套科学、完整、民主参与、可操作性强的考核管理体系。因此,要解决考核的合理性与可行性之间的矛盾,就应当在科学理论指导下,运用先进的绩效考核方法,构建非领导职务公务员考核量化管理模型,积极探索切实可行的实现路径。     

X染色体STR荧光复合扩增体系的建立及其应用

目的研究X染色体STR在法医学亲权鉴定中的应用。方法利用荧光标记引物复合PCR技术,在同一反应管中同时检测DXS6801、DXS9902、DXS6809、DXS6803、DXS6804和DXS67996个X-STR基因座,采用3100遗传分析仪电泳和GeneMapper IDv 3.1软件进行基因分型。结果本体系同时分析6个X-STR基因座,结果清晰,灵敏度高,重复性好。结论本研究的6个X-STR基因座复合扩增体系,在法医学个体识别特别是女性的亲权鉴定中有重要应用价值。     

The Recovery and Analysis of Mitochondrial DNA from Exploded Pipe Bombs*

Abstract: Improvised explosive devices (IEDs) represent one of the most common modes of arbitrarily injuring or killing human beings. Because of the heat generated by, and destruction to, an IED postconflagration, most methods for identifying who assembled the device are ineffective. In the research presented, steel pipe bombs were mock‐assembled by volunteers, and the bombs detonated under controlled conditions. The resultant shrapnel was collected and swabbed for residual cellular material. Mitochondrial DNA profiles were generated and compared blind to the pool of individuals who assembled the bombs. Assemblers were correctly identified 50% of the time, while another 19% could be placed into a group of three individuals with shared haplotypes. Only one bomb was assigned incorrectly. In some instances a contaminating profile (mixture) was also observed. Taken together, the results speak to the extreme sensitivity the methods have for identifying those who assemble IEDs, along with precautions needed when collecting and processing such evidence.     

武汉汉族人群D15S659、D6S2418、D5S1457遗传多态性

利用PCR和PAGE技术,对武汉地区汉族人群D15S659、D6S2418、D5S1457三个STR基因座进行群体调查。1材料与方法1.1样本221例武汉地区汉族无关个体抗凝血样,取自同济医院血库。1.2 DNA提取采用Chelex-100提取法提取血样DNA。1.3 3个STR基本特征和引物参数见文献。1.4 PCR扩增及电泳采用常规DNA-STR银染分型技术,参照文献。     

Rapid STR analysis of single source DNA samples in 2 h

The establishment of offender DNA databases is critical to future crime prevention. Many countries have established databases or are in the process of passing database legislation. With new legislation the number of samples that will be collected could begin to exceed the testing capacity of many labs leading to backlogs.Two bottlenecks in the workflow that can contribute to a backlog of samples are DNA purification and PCR cycling time. The average purification time is approximately 2 h and the average cycling time of current STR kits is approximately 3 h. To address the second problem we investigated alternative DNA enzymes to decrease PCR cycling time. It was necessary to balance the increase in time to result against the need to address factors which can impact interpretation of a DNA profile such as: generation of stutter products, non-template addition, intra-locus balance, accuracy, and species specificity.Initial feasibility studies demonstrate that alternative enzymes can decrease PCR cycling time. The data show that this assay can increase throughput, providing results in less than 2 h. However, decreasing PCR cycling time will have an affect on multiplex STR performance.     

Development and evaluation of multiplex Y-STR assays for application in molecular genealogy

Three multiplex PCRs were developed for the analysis of 14 single-copy and 4 multi-copy Y chromosome Short Tandem Repeat (STR) loci routinely used by several public genealogical databases. These assays were used in addition to PowerPlex^® Y for the analysis of 245 DNA samples from a genealogical project. In total 244 different haplotypes composed of 37–40 alleles were identified with one haplotype identical between two males with the same surname. The multi-copy loci DYS464 and DYS724 were the most polymorphic with a gene diversity of at least 0.964. The use of DYS454 and DYS455 can be questioned as these loci had the lowest gene diversity (0.039 and 0.269, respectively).     

书写活动的脑电图研究--笔迹鉴定原理新探之一

笔迹鉴定的基本原理除了早期的书写动作习惯论外,还有笔迹心理活动论等其他理论.由于科技发展水平的局限,对笔迹鉴定原理的研究方法尚不成熟.选择脑电图检查法来研究大脑功能和思维在书写、制作文字材料时的共性和个性、稳定性和变异性问题,被证明具有一定的探索价值.     

NDV感染的鸡胚成纤维细胞TLR7 mRNA表达的动态变化

为研究新城疫病毒(NDV)感染过程中,鸡Toll样受体7(chTLR7)表达的变化情况,采用Trizol法抽提NDV感染组和正常对照组鸡胚成纤维细胞(CEF)的总RNA,反转录成cDNA。以β-actin基因为内参,应用实时荧光定量PCR法检测细胞中chTLR7基因表达的动态变化。结果显示,CEF被NDV感染后第12、24、36、48小时,感染组chTLR7mRNA表达量分别是正常对照组的18.63、0.05、1.37、10.62倍,组间差异均极显著(P<0.01)。结果提示,chTLR7可能参与了NDV感染CEF的早期过程。