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Use of Genetically Variant Peptides to Statistically Estimate the Genetic Background of Hair Shafts

NCJ Number
Glendon Parker
Date Published
13 pages

This project tested a central hypothesis that proteomic genotyping can estimate the ancestry of an individual who donates a hair shaft; and that this can be obtained by maximizing the efficiency of hair sample processing, followed by applying the optimized sample processing protocol to enough subjects (n=170) from a range of genetic backgrounds to test the hypothesis.



Based on the data produced from this project or otherwise published, the researchers concluded that hair shaft processing methods are better when large amounts of reductant are used, and gentle chemical methods are applied. This produced a three-fold improvement in data yields from a single hair shaft. The project discovered and characterized 497 genetically varied peptides (GVPs). The genetic characterization of these GVP-inferred SNPs included those which have significant differences in their FST values and are potentially ancestry informative SNPs. The significance of this for identifying genetic characteristics from hair shafts is explained. The researchers advise that this project lays the foundation for efficient processing of hair and the ability to obtain high levels of genetic information that is useful to an investigator. Project researchers advise that a forensically relevant hair shaft can now include probabilities of a donor’s ancestry for a given likelihood ratio. 4 figures, 1 table, and 31 references