EC Dental Science

Research Article Volume 24 Issue 4 - 2025

The Truth in the Lye: Optimizing DNA, RNA, and Protein Extraction from Human Teeth Under Different Incubation Times and Environmental Conditions

Maria J Castagnola1, Mayaas Hassan1, Alixs M Pujols1, Shelby Feirstein2, Luis L Cabo2, Joe Adserias-Garriga2 and Sara C Zapico1,3*

1Department of Chemistry and Environmental Sciences, New Jersey Institute of Technology, Newark, NJ, United States
2Applied Forensic Sciences, Mercyhurst University, Erie, Pennsylvania, United States
3Anthropology Department and Laboratories of Analytical Biology, NMNH, Smithsonian Institution, Washington, DC, United States

*Corresponding Author: Sara C Zapico, Department of Chemistry and Environmental Sciences, New Jersey Institute of Technology, Newark, NJ, United States and Anthropology Department and Laboratories of Analytical Biology, NMNH, Smithsonian Institution, Washington,DC, United States.
Received: March 14, 2025; Published: April 02, 2025



Human identification is of utmost importance in criminal investigations, mass disasters, and humanitarian contexts. Short Tandem Repeats profiling has been the gold standard for DNA-based identification, but integrating RNA and protein analysis for postmortem interval estimation could significantly improve forensic investigations, particularly when traditional methods fall short. Advances in -omics technologies for skeletal remains highlight the importance of simultaneously extracting DNA, RNA, and proteins to maximize information from limited forensic samples. However, environmental conditions can significantly impact biomolecule recovery.
This study investigates the simultaneous extraction of DNA, RNA, and proteins from human teeth under different conditions. 23 third molars were analyzed in two phases. First, incubation times of 2, 5, 12, and 24 hours were tested to optimize biomolecular extraction using teeth from living donors. Second, the impact of chemical treatments (sodium hydroxide and hydrochloric acid) was evaluated on curated teeth, with a 24-hour incubation period. The Quick-DNA/RNA Miniprep Plus Kit (Zymo Research, Irvine, CA, USA) was used for extraction. Quantification was performed applying spectrophotometric and fluorometric techniques, along with a human DNA-specific quantitation method. STR analysis was performed, and statistical comparisons were carried out to compare the effect of time and treatments on the extractions.
In phase 1, DNA yield at 24 hours was significantly higher than at 2 hours and 5 hours. However, RNA and protein recovery showed no significant differences across incubation times. In phase 2, NaOH treatment significantly reduced DNA and RNA recovery compared to controls and HCl treatment. Protein recovery showed no significant differences. STR analysis produced complete DNA profiles for all samples, except two cases. Quality parameters (Degradation Index, Inhibition Control Index, Total Peak Height, Peak Height Ratio and possible dropout) indicated good-quality profiles, with the lowest values in NaOH-treated samples.
To the best of our knowledge, this is the first study to assess the simultaneous extraction of DNA, RNA, and proteins from human teeth under different environmental conditions. The results confirm that high-quality/quantity extraction is achievable, offering valuable insights for human identification and time-since-death estimation.
Keywords:Forensic Odontology; Human Identification; Human Teeth; Simultaneous Extraction; STR Profiling; Time-Since-Death Estimation; Chemical Damage; Environment

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Sara C Zapico., et al. “The Truth in the Lye: Optimizing DNA, RNA, and Protein Extraction from Human Teeth Under Different Incubation Times and Environmental Conditions”. EC Dental Science 24.4 (2025): 01-18.

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