Babol-Pokora Katarzyna, Prośniak Adam, Jacewicz Renata, Berent Jarosław
Katedry i Zakładu Medycyny Sadowej Uniwersytetu Medycznego w Łodzi.
Arch Med Sadowej Kryminol. 2009 Apr-Jun;59(2):118-23.
The most common cause of problems associated with analyzing DNA extracted from forensic samples is their high level of degradation. Such difficulties are caused by the fact that STR markers have too large amplicon sizes to be amplified in degraded DNA samples. Thus, it is necessary to employ more efficient markers for analyzing evidential samples. SNPs are ideal tools for such purposes, for the SNP genotyping method does not require large amplicon size, and thus increases the possibility of amplifying degraded DNA samples. Although single SNP is not polymorphic enough, we can obtain sufficient results by examining several SNPs. The aim of this study was to examine the usefulness of the SNP-pentaplex (rs2294067, rs2282160, rs2070764, rs2277216, rs1063739) for forensic applications by analysing several forensic cases, which were impossible to solve in a range of STR markers because of highly degraded DNA. DNA fragments were amplified in one multiplex PCR reaction, which contained 5 primer pairs. SNPs were subsequently identified in a minisequencing reaction and gel electrophoresis in an ABI Prism 377 Sequencer. The research confirmed the usefulness of SNP-pentaplex for forensic applications. Despite employing mainly degraded and low copy number DNA, full genetic profiles were obtained in almost every sample. Although the discrimination power of SNP-pentaplex is not sufficient for obtaining adequate evidential value, it seems to be an ideal screening method for forensic applications.
与分析从法医样本中提取的DNA相关的问题，最常见的原因是其高度降解。这些困难是由以下事实造成的：STR标记的扩增子大小太大，无法在降解的DNA样本中进行扩增。因此，有必要采用更有效的标记来分析证据样本。单核苷酸多态性（SNP）是用于此目的的理想工具，因为SNP基因分型方法不需要大的扩增子大小，从而增加了扩增降解DNA样本的可能性。尽管单个SNP的多态性不足，但通过检测多个SNP我们可以获得足够的结果。本研究的目的是通过分析几起法医案件来检验SNP五重检测法（rs2294067、rs2282160、rs2070764、rs2277216、rs1063739）在法医应用中的实用性，这些案件由于DNA高度降解，在一系列STR标记中无法解决。DNA片段在一个包含5对引物的多重PCR反应中进行扩增。随后在一个小测序反应和ABI Prism 377测序仪中的凝胶电泳中鉴定SNP。该研究证实了SNP五重检测法在法医应用中的实用性。尽管主要使用的是降解的和低拷贝数的DNA，但几乎在每个样本中都获得了完整的基因图谱。虽然SNP五重检测法的鉴别能力不足以获得足够的证据价值，但它似乎是法医应用中一种理想的筛查方法。
