Siriboonpiputtana T, Rinthachai T, Shotivaranon J, Peonim V, Rerkamnuaychoke B
Human Genetics Laboratory, Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Forensic Medical Laboratory, Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok 10400, Thailand.
Forensic Sci Int. 2018 Mar;284:167-175. doi: 10.1016/j.forsciint.2017.12.045. Epub 2018 Jan 8.
DNA typing from degraded human remains is still challenging forensic DNA scientists not only in the prospective of DNA purification but also in the interpretation of established DNA profiles and data manipulation, especially in mass fatalities. In this report, we presented DNA typing protocol to investigate many skeletal remains in different degrees of decomposing. In addition, we established the grading system aiming for prior determination of the association between levels of decomposing and overall STR amplification efficacy. A total of 80 bone samples were subjected to DNA isolation using the modified DNA IQ™ System (Promega, USA) for bone extraction following with STR analysis using the AmpFLSTR Identifiler (Thermo Fisher Scientific, USA). In low destruction group, complete STR profiles were observed as 84.4% whereas partial profiles and non-amplified were found as 9.4% and 6.2%, respectively. Moreover, in medium destruction group, both complete and partial STR profiles were observed as 31.2% while 37.5% of this group was unable to amplify. Nevertheless, we could not purify DNA and were unable to generate STR profile in any sample from the high destroyed bone samples. Compact bones such as femur and humerus have high successful amplification rate superior than loose/spongy bones. Furthermore, costal cartilage could be a designate specimen for DNA isolation in a case of the body that was discovered approximately to 3 days after death which enabled to isolate high quality and quantity of DNA, reduce time and cost, and do not require special tools such as freezer mill.
对降解的人类遗骸进行DNA分型，仍然是法医DNA科学家面临的挑战，这不仅体现在DNA纯化方面，还体现在对已建立的DNA图谱的解读和数据处理上，尤其是在大规模死亡事件中。在本报告中，我们介绍了用于研究不同分解程度的众多骨骼遗骸的DNA分型方案。此外，我们建立了分级系统，旨在预先确定分解程度与整体STR扩增效率之间的关联。总共80个骨样本使用改良的DNA IQ™系统（美国Promega公司）进行DNA提取，随后使用AmpFLSTR Identifiler（美国赛默飞世尔科技公司）进行STR分析。在低破坏组中，完整的STR图谱占84.4%，而部分图谱和未扩增的分别占9.4%和6.2%。此外，在中度破坏组中，完整和部分STR图谱均占31.2%，而该组中有37.5%无法扩增。然而，对于高度破坏的骨样本，我们无法在任何样本中纯化DNA并生成STR图谱。股骨和肱骨等致密骨的成功扩增率高于松质骨。此外，对于死后约3天被发现的尸体，肋软骨可以作为DNA提取的指定样本，能够分离出高质量和高数量的DNA，减少时间和成本，并且不需要冷冻研磨机等特殊工具。
