Metagenomic analyses of bacteria on human hairs: a qualitative assessment for applications in forensic science.

Content Provider	Europe PMC
Author	Tridico, Silvana R Murray, Dáithí C Addison, Jayne Kirkbride, Kenneth P Bunce, Michael
Abstract	Background Mammalian hairs are one of the most ubiquitous types of trace evidence collected in the course of forensic investigations. However, hairs that are naturally shed or that lack roots are problematic substrates for DNA profiling; these hair types often contain insufficient nuclear DNA to yield short tandem repeat (STR) profiles. Whilst there have been a number of initial investigations evaluating the value of metagenomics analyses for forensic applications (e.g. examination of computer keyboards), there have been no metagenomic evaluations of human hairs—a substrate commonly encountered during forensic practice. This present study attempts to address this forensic capability gap, by conducting a qualitative assessment into the applicability of metagenomic analyses of human scalp and pubic hair. Results Forty-two DNA extracts obtained from human scalp and pubic hairs generated a total of 79,766 reads, yielding 39,814 reads post control and abundance filtering. The results revealed the presence of unique combinations of microbial taxa that can enable discrimination between individuals and signature taxa indigenous to female pubic hairs. Microbial data from a single co-habiting couple added an extra dimension to the study by suggesting that metagenomic analyses might be of evidentiary value in sexual assault cases when other associative evidence is not present. Conclusions Of all the data generated in this study, the next-generation sequencing (NGS) data generated from pubic hair held the most potential for forensic applications. Metagenomic analyses of human hairs may provide independent data to augment other forensic results and possibly provide association between victims of sexual assault and offender when other associative evidence is absent. Based on results garnered in the present study, we believe that with further development, bacterial profiling of hair will become a valuable addition to the forensic toolkit.
Related Links	https://europepmc.org/backend/ptpmcrender.fcgi?accid=PMC4266914&blobtype=pdf
Volume Number	5
DOI	10.1186/s13323-014-0016-5
PubMed Central reference number	PMC4266914
Issue Number	1
PubMed reference number	25516795
Journal	Investigative Genetics [Investig Genet]
e-ISSN	20412223
Language	English
Publisher	BioMed Central
Publisher Date	2014-12-16
Publisher Place	London
Access Restriction	Open
Rights License	This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. © Tridico et al.; licensee BioMed Central Ltd. 2014
Subject Keyword	Forensic Metagenomics Bacteria Scalp hairs Pubic hairs Sexual assaults Next-generation sequencing 16S DNA
Content Type	Text
Resource Type	Article
Subject	Genetics Molecular Biology Pathology and Forensic Medicine