Abstract: The study used myocardial tissues of 10 forensic FFPET patients and the samples were prepared into films. The DNA was extracted using xylene-Chelex100 method, dewaxing solution-Chelex100 method, dewaxing solution-Vazyme FastPure FFPE DNA Isolation kit (abbreviated as FP kit) and dewaxing solution-Beijing Tiangen paraffin-embedded tissue genome extraction kit (abbreviated as Tiangen kit), and determined by ultraviolet spectrophotometer for concentration and purity, and short tandem repeats (STR) typing test (23 autosomes). The extraction quality, STR typing quality and detection rate of FFPET in four different extraction methods were compared and analyzed to find an efficient, simple, economical, practical, and convenient method. The results showed that for the quality of extrated DNA, the concentration of DNA extracted by two Chelex100 methods were higher than the two test kits, and the purity of DNA extracted by the kits were superior to that of the other two methods. The differences were statistically significant (P<0.05). The average concentration and purity of DNA extracted by FP kit were superior to those by Tiangen kit without significant differences (P>0.05). For the quality of STR typing and detection rate, STR typing generally shows the imbalance of amplification between different loci and different alleles of the same locus, with the former being higher and the later lower. The average detection rate of STR was in the order of: FP kit >Tiangen kit>Chelex100 method. There were no significant difference in the detection rates of STR loci between the two Chelex100 methods (P>0.05), whereas there were significant differences between them and the other two methods (P<0.05). There was a significant difference between the FP kit and Tiangen kit (P<0.05). Therefore when dealing with difficult samples such as formaldehyde-fixed paraffin-embedded tissues in forensic DNA identification cases, the dewaxing solution-Vazyme FastPure FFPE DNA Isolation kit was superior to the other three DNA extraction methods.
Key words: formalin-fixed paraffin-embedded tissue; forensic examination materials; difficult inspection materials; method comparison
（Acta Laser Biology Sinica, 2023, 32(5): 441-449）