NCJ Number
229284
Journal
Journal of Forensic Sciences Volume: 54 Issue: 6 Dated: November 2009 Pages: 1411-1413
Date Published
November 2009
Length
3 pages
Annotation
This study analyzed degradation in both the quantity and quality of DNA for 24 extracted teeth after storage at room temperature for 0, 2, 5, and 10 years.
Abstract
As expected, the highest concentration of DNA was found in teeth stored for the shortest period. Statistical analysis with one-way ANOVA showed a significant difference in DNA concentrations according to elapsed storage interval. The Tukey HSD test showed statistically significant differences between DNA concentration in fresh teeth (0 years) and in the other groups (2, 5, and 10 years). No significant differences were found between the 2, 5, and 10-year groups. The concentration of DNA declined significantly for the first 2 years, but with no significant decline in the mean concentration of DNA between 2 and 10 years. The study was able to quantify DNA in most of the samples (87.5 percent); however, no DNA was obtained from three samples: two teeth from the 5-year storage interval group and one tooth from the 10-year storage interval. As expected, more DNA was obtained from healthy teeth, molars, and premolars due to the number of roots and the increasing size of the pulp chamber in distal positions. The decontamination procedure used to treat the sample is another factor that can alter DNA degradation. Of the many techniques available to decontaminate, this study used a three-step procedure: physical removal of the enamel, washing with bleach, and exposure to ultraviolet light. The study analyzed healthy teeth that were free of disease or previous treatments. Short tandem repeat (STR) genotyping was the analytical method used for DNA analysis. Additional research is needed to control for individual and external factors that could affect DNA. 2 figures and 15 references