Two simplified tooth sample preparation methods for conventional laboratory and RapidHIT™ ID workflows

Area of Science:

• Forensic Science
• Genetics
• Anthropology

Background:

• Disaster victim identification (DVI) is crucial after mass casualty events.
• Human dental remains offer a valuable source of nuclear DNA when soft tissues degrade.
• Traditional forensic DNA workflows require extensive sample preparation by trained personnel.

Purpose of the Study:

• To evaluate simplified sample preparation protocols for tooth DNA extraction.
• To compare the efficacy of conventional forensic DNA workflows with the Applied Biosystems® RapidHIT™ ID instrument for DVI.

Main Methods:

• Ten deciduous teeth were processed using two simplified protocols.
• Samples were fragmented using a claw hammer for RapidHIT™ ID or pulverized with a coffee grinder for traditional workflows.
• Short tandem repeat (STR) allele detection and peak height ratios (PHRs) were analyzed.

Main Results:

• Comparable STR allele detection rates were observed between RapidHIT™ ID (99.0%) and GlobalFiler™ (99.8%).
• Average intralocus heterozygote PHRs were similar: RapidHIT™ ID (0.80) and GlobalFiler™ (0.86).
• The RapidHIT™ ID workflow flagged 90% of samples for review, with 91% of alleles passing quality metrics versus 100% for GlobalFiler™.

Conclusions:

• Simplified, low-tech tooth fragmentation followed by RapidHIT™ ID analysis can generate complete STR profiles from aged dental samples.
• Further research is needed to refine protocols for challenging samples and enable field-based DVI.
• These methods show promise for improving the speed and accessibility of DVI processes.