Teeth are relatively firm compare to other organs and stable to a variety of environment such as heat and putrefaction, therefore they are foresically significant samples in sex and age determination, blood typing and DNA typing.
The author conducted the experiment on heated teeth to detect mitochondrial DNA related to individual identification in high temperature.
The experiment was done on 33 teeth of unrelated Koreans consisted of heated ones to 100°C, 150°C, 200°C, 250°C, 300°C for 1 hour and 2 hours respectively and to 350°C for 1 hour. DNA was extracted from each tooth and amplified hypervariable region 1 of mitochondrial DNA by Polymerase Chain Reaction(PCR). Then mitochondrial DNA sequencing data was analysed according to the Anderson sequence and the followings are the results :
1. It was able to analyse mitochondrial DNA of 30 heated teeth to 300°C for 2 hours.
2. It was comfirmed 29 mitochondrial lineages from 30 teeth of unrelated Koreans.
3. Among the sequences 45 nucleotide sites are polymorphic, 39 nucleotides of which is substituted by transition and 6 nucleotides by transversion.
4. The most frequent polymorphisms were found at the position 16,223(C to T transition) and 16,362(T to C transition)
As a result, it is possible to extract DNA from charred teeth, therefore teeth can be used as a source of mitochondrial DNA for individual identification expecially when nuclear DNA is not extracted in charred body in high temperature.
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