Time-dependent changes in DNA stability in decomposing teeth over 18 months.
OBJECTIVE
The objective was to use a dual quantitative and qualitative approach to analyze the dental DNA degradation produced by the passage of time since tooth death under controlled environmental conditions.


METHODS
Sixty human teeth were stored at room temperature for 0, 1, 3, 6, 12 or 18 months post-extraction. DNA quantification was determined by real-time quantitative PCR using a Quantifiler(TM) kit. DNA quality was assessed by the allelic dropout ratio between the smallest and largest loci obtained after STR genotyping and using an AmpFlSTR® Identifiler™ PCR kit. We also evaluated differences of DNA concentration related to gender and tooth position.


RESULTS
DNA concentration significantly reduced in 1 month post-extraction, stabilized between 1-12 months post-extraction, but decreased again at 18 months post-extraction. Interestingly, a significant reduction of the allelic dropout ratio (DNA quality) was only detected at 18 months post-extraction.


CONCLUSIONS
Stability of dental DNA decreased over time, differently affecting the amount and quality of the DNA in a time-dependent process over the first 18 months post-extraction. These results have a potential use in post-mortem intervals in human teeth in controlled environmental conditions.
Department of Forensic Medicine, University of Malaga, Malaga, Spain.
Leticia
L
Rubio
Ignacio
I
Santos
Maria Jesus
MJ
Gaitan
Stella
S
Martin de-las Heras
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D004247:DNA / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D014070:Tooth / Q000378:metabolism*; D055815:Young Adult
D004247:DNA