Lisman Dagmara, Ossowski Andrzej, Tołoczko-Grabarek Aleksandra, Kozłowski Mateusz, Cymbaluk-Płoska Aneta
Department of Genomic and Forensic Genetics, Pomeranian Medical University in Szczecin, 70-111 Szczecin, Poland.
Department of Pathomorphology, Pomeranian Medical University in Szczecin, University Clinical Hospital No. 2 in Szczecin, 70-111 Szczecin, Poland.
Genes (Basel). 2025 Sep 12;16(9):1074. doi: 10.3390/genes16091074.
Obtaining reliable DNA profiles from archival tissue preserved as formalin-fixed, paraffin-embedded (FFPE) samples remains a major challenge in both forensic and medical evaluations. The quality of DNA isolated from FFPE material is frequently compromised due to formalin-induced fragmentation and chemical modifications. These limitations are particularly relevant in cases of suspected medical malpractice related to cancer diagnosis or treatment, where retrospective molecular analyses may provide critical evidence. The aim of this study was to evaluate the performance of the Maxwell RSC Xcelerate DNA FFPE Kit (Promega) in generating DNA profiles from archival FFPE tissue blocks of endometrial cancer and to identify the limitations associated with this approach. Archival FFPE blocks of endometrial cancer were analyzed using the Maxwell RSC Xcelerate DNA FFPE Kit. DNA yield, purity, and degradation indices were assessed using standard real-time PCR-based quantification methods. Short tandem repeat (STR) profiling was performed with forensic genotyping kits, and the completeness, allele balance, and reliability of obtained profiles were evaluated. The obtained results were compared with reference quality thresholds commonly used in forensic practice. The Maxwell RSC Xcelerate Kit allowed for recovery of relatively high DNA yields with consistently low degradation indices, confirming good extraction efficiency from FFPE samples. Nevertheless, despite favorable quantitative values, the generation of complete STR profiles was often unsuccessful. Partial or incomplete profiles were frequent, characterized by allele dropout and imbalance, which substantially reduced their evidentiary value. These findings suggest that DNA fragmentation and fixation-related artifacts impair amplification efficiency and limit the usefulness of STR analysis. This study emphasizes the persistent challenges of DNA profiling from FFPE tissue in forensic-medical contexts. Although the Maxwell RSC Xcelerate Kit demonstrated effective DNA recovery, the ability to generate complete and interpretable STR profiles remained limited. Further refinement of extraction protocols, as well as improved interpretative strategies, are required to enhance the reliability and evidentiary significance of molecular analyses based on archival FFPE material.
从以福尔马林固定、石蜡包埋（FFPE）样本形式保存的存档组织中获取可靠的DNA图谱，在法医和医学评估中仍然是一项重大挑战。由于福尔马林引起的片段化和化学修饰，从FFPE材料中分离出的DNA质量常常受到影响。这些限制在与癌症诊断或治疗相关的疑似医疗事故案件中尤为重要，因为回顾性分子分析可能会提供关键证据。本研究的目的是评估Maxwell RSC Xcelerate DNA FFPE试剂盒（Promega公司）从子宫内膜癌存档FFPE组织块中生成DNA图谱的性能，并确定与该方法相关的局限性。使用Maxwell RSC Xcelerate DNA FFPE试剂盒对子宫内膜癌的存档FFPE组织块进行分析。使用基于实时PCR的标准定量方法评估DNA产量、纯度和降解指数。使用法医基因分型试剂盒进行短串联重复序列（STR）分型，并评估所获得图谱的完整性、等位基因平衡和可靠性。将获得的结果与法医实践中常用的参考质量阈值进行比较。Maxwell RSC Xcelerate试剂盒能够回收相对较高的DNA产量，且降解指数始终较低，证实了从FFPE样本中具有良好的提取效率。然而，尽管定量值良好，但完整STR图谱的生成往往不成功。部分或不完整的图谱很常见，其特征是等位基因缺失和不平衡，这大大降低了它们的证据价值。这些发现表明，DNA片段化和固定相关的假象会损害扩增效率，并限制STR分析的实用性。本研究强调了在法医医学背景下从FFPE组织进行DNA分型所面临的持续挑战。尽管Maxwell RSC Xcelerate试剂盒展示了有效的DNA回收能力，但生成完整且可解释的STR图谱的能力仍然有限。需要进一步完善提取方案以及改进解释策略，以提高基于存档FFPE材料的分子分析的可靠性和证据意义。
