Institute of Legal Medicine, University Hospital Düsseldorf, Heinrich Heine University, Düsseldorf, Germany.
Department of Archaeology & Coin Cabinet, Joanneum Universal Museum, Graz, Austria.
Int J Legal Med. 2021 Jul;135(4):1225-1233. doi: 10.1007/s00414-021-02522-1. Epub 2021 Feb 17.
Age at death estimation in cases of human skeletal finds is an important task in forensic medicine as well as in anthropology. In forensic medicine, methods based on "molecular clocks" in dental tissues and bone play an increasing role. The question, whether these methods are applicable also in cases with post-depositional intervals far beyond the forensically relevant period, was investigated for two "protein clocks", the accumulation of D-aspartic acid (D-Asp) and the accumulation of pentosidine (Pen) in dentine. Eight teeth of skeletons from different burial sites in Austria and with post-depositional intervals between c. 1216 and c. 8775 years were analysed. The results of age at death estimation based on D-Asp and Pen in dentine were compared to that derived from a classical morphological examination. Age at death estimation based on D-Asp resulted consistently in false high values. This finding can be explained by a post-mortem accumulation of D-Asp that may be enhanced by protein degradation. In contrast, the Pen-based age estimates fitted well with the morphological age diagnoses. The described effect of post-mortem protein degradation is negligible in forensically relevant time horizons, but not for post-depositional intervals of thousands of years. That means that the "D-Asp clock" loses its functionality with increasing post-depositional intervals, whereas Pen seems to be very stable. The "Pen-clock" may have the potential to become an interesting supplement to the existing repertoire of methods even in cases with extremely long post-depositional intervals. Further investigations have to test this hypothesis.
人类骨骼遗骸的年龄推断在法医学和人类学中都是一项重要的任务。在法医学中，基于牙齿组织和骨骼中“分子钟”的方法发挥着越来越重要的作用。这些方法是否也适用于死后间隔远超法医学相关时期的情况，这一问题已经针对两种“蛋白质钟”——牙本质中 D-天冬氨酸（D-Asp）的积累和戊糖素（Pen）的积累——进行了研究。分析了来自奥地利不同墓地的 8 颗骨骼牙齿，其死后间隔约为 1216 年至 8775 年。基于牙本质中 D-Asp 和 Pen 的死亡年龄推断结果与经典形态学检查得出的结果进行了比较。基于 D-Asp 的死亡年龄推断结果始终偏高，这一发现可以用死后 D-Asp 的积累来解释，这种积累可能是由于蛋白质降解增强所致。相比之下，基于 Pen 的年龄估计与形态学年龄诊断相符。在法医学相关时间范围内，描述的死后蛋白质降解效应可以忽略不计，但对于几千年的死后间隔则不然。这意味着，随着死后间隔的增加，“D-Asp 钟”的功能会丧失，而 Pen 似乎非常稳定。“Pen 钟”即使在死后间隔非常长的情况下，也可能成为现有方法组合的一个有趣补充。进一步的研究必须检验这一假设。
