2016年9月7日，国际知名学术期刊《PLOS ONE》在线发表了美国劳伦斯利弗莫尔国家实验室生物化学家格兰登·帕克的一篇研究论文，研究报道了一项最新技术：头发中的独特蛋白质标记同样可以用于身份识别，让那些犯罪分子无所遁形。

DNA检测技术已在寻找罪犯方面发挥很大威力。但DNA检测不是找到犯罪分子的唯一手段。每个人的DNA都是独一无二的，这是DNA检测常用于犯罪调查或考古研究的原因所在。但这一手段也存在不足，因为随着时间的流逝，环境变化会造成DNA信息缺失，导致无法通过多酶链式反应(PCR)将微量DNA大幅增加来放大信息，以便进行比对。相比之下，蛋白质的化学稳定性更强，存续时间更长，且同样是独一无二的。那么，头发中的蛋白质是否可以作为身份识别的另一个有效工具呢?这正是的研究目标。

帕克及其同事发表论文称，他们对6具卒于250年前的考古残骸及活在当下的76个欧裔、非裔美国人的头发样本进行了分析，找到了185个蛋白质标记。他们认为，通过这些蛋白质标记，足以在百万人群中找到要找的一个人。研究小组希望能在这100多个蛋白质中确认一组核心蛋白质标记物，使通过一根头发就可在茫茫人海中找到目标成为可能，从而为犯罪调查和考古研究提供DNA检测之外的另一个有效工具。

参与研究的劳伦斯利弗莫尔国家实验室法医学中心主任、化学家布拉德·哈特表示，目前基于蛋白质进行身份识别的技术发展状况，与当初DNA检测手段发展初期十分类似，但要将这种足以改变游戏规则的方法应用于实际工作中，还需进行更多研究。

原文链接：

Demonstration of Protein-based human Identification Using the Hair Shaft Proteome

原文摘要：

Human identification from biological material is largely dependent on the ability to characterize geneticpolymorphisms in DNA. Unfortunately, DNA can degrade in the environment, sometimes below the level at which it can be amplified by PCR. Protein however is chemically more robust than DNA and can persist for longer periods. Protein also contains genetic variation in the form of single amino acid polymorphisms. These can be used to infer the status of non-synonymous single nucleotide polymorphism alleles. To demonstrate this, we used mass spectrometry-based shotgun proteomics to characterize hair shaft proteins in 66 European-American subjects. A total of 596 single nucleotide polymorphism alleles were correctly imputed in 32 loci from 22 genes of subjects’ DNA and directly validated using Sanger sequencing. Estimates of the probability of resulting individual non-synonymous single nucleotide polymorphism allelic profiles in the European population, using the product rule, resulted in a maximum power of discrimination of 1 in 12,500. Imputed non-synonymous single nucleotide polymorphism profiles from European–American subjects were considerably less frequent in the African population (maximum likelihood ratio = 11,000). The converse was true for hair shafts collected from an additional 10 subjects with African ancestry, wher some profiles were more frequent in the African population. Genetically variant peptides were also identified in hair shaft datasets from six archaeological skeletal remains (up to 260 years old). This study demonstrates that quantifiable measures of identity discrimination and biogeographic background can be obtained from detecting genetically variant peptides in hair shaft protein, including hair from bioarchaeological contexts.