Netherlands Forensic Institute, Digital Technology and Biometrics, Laan van Ypenburg 6, 2497 GB, Den Haag, Netherlands.
Delft University of Technology, Faculty of Applied Sciences, Department of Chemical Engineering, Van der Maasweg 9, 2629 HZ, Delft, The Netherlands.
Sci Rep. 2018 Nov 6;8(1):16425. doi: 10.1038/s41598-018-34791-z.
Fingermarks are trace evidence of great forensic importance, and their omnipresence makes them pivotal in crime investigation. Police and law enforcement authorities have exploited fingermarks primarily for personal identification, but crucial knowledge on when fingermarks were deposited is often lacking, thereby hindering crime reconstruction. Biomolecular constituents of fingermark residue, such as amino acids, lipids and proteins, may provide excellent means for fingermark age determination, however robust methodologies or detailed knowledge on molecular mechanisms in time are currently not available. Here, we address fingermark age assessment by: (i) drafting a first protein map of fingermark residue, (ii) differential studies of fresh and aged fingermarks and (iii), to mimic real-world scenarios, estimating the effects of donor contact with bodily fluids on the identification of potential age biomarkers. Using a high-resolution mass spectrometry-based proteomics approach, we drafted a characteristic fingermark proteome, of which five proteins were identified as promising candidates for fingermark age estimation. This study additionally demonstrates successful identification of both endogenous and contaminant proteins from donors that have been in contact with various bodily fluids. In summary, we introduce state-of-the-art proteomics as a sensitive tool to monitor fingermark aging on the protein level with sufficient selectivity to differentiate potential age markers from body fluid contaminants.
指纹是具有重要法医学意义的痕迹证据，由于其普遍存在，因此在犯罪调查中起着关键作用。警方和执法机构主要利用指纹进行个人识别，但通常缺乏关于指纹何时留下的关键信息，从而阻碍了犯罪重建。指纹残留物中的生物分子成分，如氨基酸、脂质和蛋白质，可能为指纹年龄确定提供极好的手段，然而目前尚无强大的方法或关于时间内分子机制的详细知识。在这里，我们通过以下方式解决指纹年龄评估问题：（i）起草指纹残留物的第一张蛋白质图谱，（ii）对新鲜和陈旧指纹进行差异研究，以及（iii）为了模拟真实情况，估计供体与体液接触对潜在年龄生物标志物识别的影响。我们使用基于高分辨率质谱的蛋白质组学方法起草了特征性的指纹蛋白质组，其中有五种蛋白质被鉴定为指纹年龄估计的有前途的候选物。这项研究还成功地从与各种体液接触过的供体中鉴定出内源性和污染物蛋白质。总之，我们将最先进的蛋白质组学作为一种敏感的工具引入，以在足够的选择性的基础上监测蛋白质水平上的指纹老化，从而将潜在的年龄标记物与体液污染物区分开来。
