The Study of the Yield of DNA Extracted From Hairs of Postmortem Cases

Background: Problems frequently occur from hair extraction are low concentration and impurity of DNA. Methods: Hairs from 30 postmortem cases were collected. In each case, 5 and 10 hair roots were extracted DNA by Phenol/Chloroform/Isoamyl alcohol. The amount and purity of DNA (A260/280) were detected by NanoDrop spectrophotometer. The quality of DNA was examined using polymerase chain reaction (PCR). Amount of DNA was analyzed compared with gender, age, and manner of death. Results: The amount and purity of DNA extracted from 10 hair roots were slightly better than 5 hair roots (P > .05). The mean (range) of DNA concentration was 200.4 (35.2 - 799.6) ng/µL from 10 hair roots vs 148.2 (21.7 - 571.5) ng/µL from 5 hair roots in 30 µL volume whereas the mean (range) of A260/280 was 1.61 (1.31 - 1.99) in 10 hair roots vs 1.54 (1.32 - 1.90) in 5 hair roots. The results from NanoDrop showed no difference among various gender, age, and manners of death. Conclusions: DNA can be extracted from hair by Phenol/Chloroform/Isoamyl alcohol. The quantity and quality of DNA were good enough for personal identification by PCR. DNA extracted from 10 hair roots is better than 5 hair roots.