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Abstract: A feasibility study of short tandem repeat (STR) genotyping of telogen phase hairs in particular, and hair shaft in general, is presented. A number of extraction procedures in common use were investigated and the quantities of nuclear DNA (nuDNA) delivered were quantified via a real-time PCR assay. The extracts were subjected to two variations on AmpFℓSTR® Profiler Plus™ PCR amplification strategies (extended cycles, two rounds of PCR) and the genotypes compared. Nuclear DNA was found to persist in human hair shafts, albeit at very low levels. Full Profiler Plus™ profiles consistent with the hair donor were obtained from 100mg hair shaft samples (bleached and unbleached). These were, however, mixed profiles, indicating low copy number (LCN) contamination in the extracts. Single telogen hair clubs and single hair shafts delivered partial profiles with usually only one allele of heterozygous loci. Telogen phase hairs yielded the same amount of nuDNA (and no more) as hair shafts (either anagen or telogen). Whether hair shafts dissolved or not in lysis buffer had no effect on either the quantitated yield of DNA or on the chance of obtaining a correct genotype. These results provide evidence that genomic DNA resides on the exterior of the hair shaft and we use this information to suggest an optimal procedure for nuDNA extraction from keratinised hair samples: soaking hairs in simple digestion buffers containing Tris–HCl, a salt and a chelating agent without prior cleaning of the hair shafts. It is proposed that cleaning removes most of the recoverable DNA. This procedure was applied to obtain genotypes from 3cm hair shafts which matched reference profiles from the donors at up to 9 out of 10 AmpFℓSTR® Profiler Plus™ STR loci. When the genotyping success was measured by counting the number of matches between the two dominant alleles at each locus for each extract with the reference DNA profile of the hair donor, the success was found to be highly dependent on the donor. The number of matching alleles varied between not less than 10 for one donor to no more than two for another donor. These results may well be linked to the environmental experience of the hairs from each donor prior to removal. [Copyright &y& Elsevier]

Abstract: We present a review of the literature on procedures for obtaining short tandem repeat (STR) genotypes from keratinised hair, being either hair shaft or telogen phase (naturally shed) hairs without associated scalp, follicle or sheath cells. Both the hair shaft and the telogen hair club have been subjected to the DNA-degrading keratinisation process and are more likely to be found at a crime scene than anagen (plucked) or catagen phase hairs. We discuss human hair structure, the human hair growth cycle, the keratinisation process and their implications for DNA extraction procedures, PCR amplification strategies and the interpretation of STR genotypes. Knowledge gaps and areas requiring research are identified and are the subject of a second article in this series. [Copyright &y& Elsevier]

Abstract: Wildlife crime, the illegal trade in animals and animal products, is a growing concern and valued at up to US$20 billion globally per year. Australia is often targeted for its unique fauna, proximity to South East Asia and porous borders. Marsupials of the order Diprotodontia (including koala, wombats, possums, gliders, kangaroos) are sometimes targeted for their skin, meat and for the pet trade. However, species identification for forensic purposes must be underpinned by robust phylogenetic information. A Diprotodont phylogeny containing a large number of taxa generated from nuclear and mitochondrial data has not yet been constructed. Here the mitochondrial (COI and ND2) and nuclear markers (APOB, IRBP and GAPD) are combined to create a more robust phylogeny to underpin a species identification method for the marsupial order Diprotodontia. Mitochondrial markers were combined with nuclear markers to amplify 27 genera of Diprotodontia. Data was analysed using a likelihood method. The combined data set resolved two suborders: Vombatiformes and Phalangeriformes. Phalangeriformes was subsequently split into two clades. The first clade contained the Macropodiformes and Burramyidae. The second clade contained Petauridae, grouping with Phalangeroidea. Of the markers tested, ND2 provided the greatest level of diagnostic accuracy and could be used as a forensic species identification tool for Diprotodonts, with appropriate validation. [Copyright &y& Elsevier]

Abstract: In 2010 the Australia New Zealand Policing Advisory Agency National Institute of Forensic Science (NIFS) established a project to set up a sustainable mechanism for the development and maintenance of standards, across a broad science and technology base that is relevant to general law enforcement, and the forensic science community. The project includes four core forensic standards covering the collection, analysis, interpretation and reporting of forensic evidence and discipline specific standards. One specific standard identified covers specifications regarding the manufacture of products used to collect biological material for forensic analysis. This is significant as contamination events caused by staff during the manufacturing process have resulted in investigations being hampered by non-case related DNA profiles obtained during case work analysis. The core standards continue to be developed as Australian Standards, however the contamination minimisation standard is being progressed through ISO. The development of the standards and potential impact is discussed. [Copyright &y& Elsevier]