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Disaster victim identification (DVI) refers to the forensic identification of unknown individuals following a mass disaster event. Human dental structures can contain viable DNA sources when other soft tissues are compromised. However, labor‐intensive sample preparation performed by extensively trained personnel is needed to expose the nuclear material for traditional forensic DNA workflows. With this in mind, we evaluated two simplified sample preparation protocols for processing tooth samples using either a conventional forensic DNA workflow or the Applied Biosystems® RapidHIT™ ID instrument. Briefly, sample sets for both protocols included 10 deciduous teeth that were cleaned prior to either fragmentation with a claw hammer (for RapidHIT™ ID processing) or fine‐powder pulverization with a consumer‐grade coffee grinder (for traditional workflows). The average percentage of expected STR alleles that were detected above analytical threshold for these tooth samples were comparable between methods: RapidHIT™ ID = 99.0% and GlobalFiler™ = 99.8%. Average intralocus heterozygote peak height ratios (PHRs) were comparable: RapidHIT™ ID = 0.80 and GlobalFiler™ = 0.86. Importantly, 9 of 10 samples analyzed via the RapidHIT™ ID required analyst review for flagged artifact peaks and quality issues. Across all profiles, 91% of alleles passed quality metrics for the RapidHIT™ workflow versus 100% for conventional GlobalFiler™ analysis. Collectively, these results suggest that quick, low‐tech tooth sample fragmentation followed by analysis with the RapidHIT™ ID instrument can produce complete STR profiles from aged tooth samples. Future studies should include larger samples sets, more challenging tooth samples, and further simplification of sample preparation to enable field‐forward, on‐scene DVI. [ABSTRACT FROM AUTHOR]

Insects have long played a role in forensic investigations and can be used to estimate minimum time since death, corpse translocation, and link an individual to a crime scene. Bed bugs (Cimex lectularius) are wingless ectoparasitic insects of potential forensic utility, given that all mobile life stages feed on vertebrate blood. Successful profiling of autosomal short tandem repeats (STRs) from human DNA isolated from bed bugs has been previously reported. This proof‐of‐concept study looked to expand this work and determine any possible limitations of using bed bugs for both rapid stain identification (RSID™) for human blood and Y‐STR profiling. To achieve this, bed bugs were fed either human male only or human pooled (female:male) blood for 30 min and subsequently collected at 12‐h intervals up to 108 h post‐blood meal (PBM). RSID™ blood testing was successful from the bed bug carcass remaining after DNA isolation, regardless of blood meal type and time of collection PBM. Complete Y‐STR profiles were generated from bed bugs <60 h PBM. As the time PBM increased, DNA quantity decreased, while the degradation index increased. Collection of bed bugs at a crime scene could provide a valuable source of human blood for Y STR profiling and be used to link an individual to a crime scene or for potential male suspect exclusion. Future studies should look to replicate the results of this proof‐of‐concept study with larger numbers of bed bugs, more diverse blood donors, and additional STR profiling kits. [ABSTRACT FROM AUTHOR]

Rapid DNA technology is being utilized for reference profiles worldwide. There is also strong data in the literature to support its use for high‐template DNA sources, the same is not true for low‐template sources, such as touch DNA; this is a requirement before wider implementation to forensic casework is considered. We report on the Rapid HIT Intel cartridge's ability to facilitate successful amplification of touch DNA to obtain profiles from template deposited on items commonly encountered in forensic casework. Eight items were touched in ten replicates— two were tapelifted, three swabbed, and three directly inserted. Significance was observed in the alleles amplified and RFU with respect to sample type. Three samples performed well: cable tie, fabric, and matchstick. As two of these were directly inserted, this should be considered for any sample small enough. Placement of highly absorbent substrates into the cartridge is not advised as it can cause a lysate‐pull error. Heterozygote loci often presented as homozygous (32%–78% loci per profile); this was influenced by substrate type and profile RFU. Loci with larger masses exhibited higher false homozygosity also. Comparison of the donor's profile analyzed was performed against previous datasets analyzing touch DNA through standard workflow, including manual DNA extraction, PCR, and CE separation. These data show that for all substrates, except for a fabric swatch, standard processing is preferential to Rapid HIT analysis. In its current form, rapid DNA technology is not fit for the routine analysis of touch DNA samples in forensic casework. [ABSTRACT FROM AUTHOR]