Examination of amino acid hydrogen isotope measurements of scalp hair for region-of-origin studies.
Examination of amino acid hydrogen isotope measurements of scalp hair for region-of-origin studies.
复制标题
检查头皮毛发的氨基酸氢同位素测量值，以进行起源区域研究。
DOI：
10.1002/rcm.9442
复制
发表时间：
2023
期刊：
影响因子：
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通讯作者：
Newsome,SethD
中科院分区：
文献类型：
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作者：
Mancuso,ChristyJ;Ehleringer,JamesR;Newsome,SethD
角状体组织的氢同位素（δ2H）分析已用于法医学，以重建个人的旅行史或确定其起源地区。在这里，我们使用一种化合物特异性方法来检查单个氨基酸δ 2h值与当地自来水、大块头皮发组织和原产地的关系。方法我们从美国28个地点匿名收集的头皮头发（n= 67）和自来水中测量氨基酸的δ 2h值。样品被水解成其组成氨基酸，与内部标准物质一起衍生，并使用GC - C - IRMS系统进行三份分析。结果各大洲自来水样品中氨基酸δ2H值及其对应的氨基酸δ2H值存在系统性差异。丙氨酸、谷氨酸和甘氨酸的氢同位素值与自来水显著相关，估计这些aanes中42% ~ 51%的氢原子来自自来水。我们使用线性判别分析（LDA）来探索头皮发块组织和氨基酸δ 2h值的区域模式。对于包含AANESSdata的模型，87%的方差由第一个线性判别轴（LD1）解释，并由大量毛发组织、丙氨酸和脯氨酸驱动。该模型的总体重分类成功率为72%，其中来自南部和西北地区的样本重分类正确率分别为92%和78%。在包含aaess数据的模型中，LD1解释了81%的变异，并驱动了毛发、苏氨酸、缬氨酸、苯丙氨酸和异亮氨酸。纳入aaess的模型总体重分类率为70%。结论aaness和aaess的δ 2h分析可以同时提供食物和自来水中氢对组织合成的输入信息，从而有助于改进人类和野生动物法医的地理定位模型。
RationaleHydrogen isotope (δ2H) analysis of keratinaceous bulk tissues has been used in forensic science to reconstruct an individual's travel history or determine their region‐of‐origin. Here, we use a compound‐specific approach to examine patterns of individual amino acidδ2H values in relation to those of local tap water, bulk scalp hair tissues, and region‐of‐origin.MethodsWe measuredδ2H values of amino acids in anonymously collected scalp hair (n= 67) and tap water from 28 locations in the United States. Samples were hydrolyzed into their constituent amino acids, derivatized alongside in‐house reference materials, and analyzed in triplicate using a GC‐C‐IRMS system.ResultsNon‐essential amino acid (AANESS)δ2H values and their corresponding tap water samples varied systematically across continental regions. Hydrogen isotope values of alanine, glutamic acid, and glycine were significantly correlated with tap water and an estimated 42%–51% of the hydrogen atoms in these AANESSwere derived from tap water. We used linear discriminate analysis (LDA) to explore regional patterns in scalp hair bulk tissue and amino acidδ2H values. For the model that included AANESSdata, 87% of the variance was explained by the first linear discriminant axis (LD1), and was driven by bulk hair tissue, alanine, and proline. This model had an overall 72% successful reclassification with samples from the south and northwest regions reclassifying correctly 92% and 78% of the time, respectively. For the model that included AAESSdata, LD1 explained 81% of the variation and was driven bulk hair, threonine, valine, phenylalanine, and isoleucine. The overall reclassification rate for the model that included AAESSwas 70%.ConclusionsOur findings suggest thatδ2H analyses of AANESSand AAESScould help improve geolocation models for human and wildlife forensics by simultaneously providing information about both dietary and tap water inputs of hydrogen to tissue synthesis.