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In Situ Detection of Bacteria within Paraffin-embedded Tissues Using a Digoxin-labeled DNA Probe Targeting 16S rRNA
Published on: May 21, 2015
Genotypic comparison of bacteria recovered from human bite marks and teeth using arbitrarily primed PCR
M Rahimi1, N C K Heng, J A Kieser
1Department of Oral Sciences, University of Otago School of Dentistry, Dunedin, New Zealand.
Journal of Applied Microbiology
|October 22, 2005
Summary
Genotypic analysis of oral streptococci from bite marks can identify the biter. This method provides a novel forensic tool when perpetrator DNA is unavailable.
Area of Science:
- Forensic microbiology
- Genetics
- Bite mark analysis
Background:
- Oral streptococci are abundant on human teeth.
- Genotypic analysis offers potential for individual identification.
Purpose of the Study:
- To assess the feasibility of matching oral streptococci from bite marks to the biter for forensic purposes.
- To establish proof of concept for using streptococcal genotypes as forensic evidence.
Main Methods:
- Oral streptococci were isolated from eight volunteers.
- Arbitrarily primed PCR (AP-PCR) was used to genotype streptococcal strains.
- A simulated bite mark was analyzed and compared to participant profiles.
Main Results:
- 106 distinct streptococcal genotypes were identified among participants.
- AP-PCR successfully matched bacteria from a simulated bite mark to the biter.
- Bacterial genotypes remained stable over 12 months and were unique to individuals.
Conclusions:
- Oral streptococci from bite marks can be genotypically cataloged and matched to the source.
- This technique offers a valuable forensic alternative when perpetrator DNA is not recoverable.
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