個人識別を目的としたパラフィン包埋組織からのDNA抽出法の比較

Abstract

Formalin-fixed paraffin-embedded (FFPE) tissues are one of the most effective tools for human identification in forensic science. To evaluate the effectiveness for human identification, we compared the following six methods for the extraction of DNA from FFPE tissues; EZ1 DNA Investigator Kit, ReliaPrep FFPE gDNA Miniprep System, DNA Isolator PS-Rapid Reagent, QIAamp DNA FFPE Tissue Kit, NucleoSpin DNA FFPE XS and phenol-chloroform method. DNA extracted using each method from two FFPE tissue blocks were quantified by three different DNA quantification methods (Quant-it dsDNA HS Assay Kit and quantitative PCR based on 207 bp and 98 bp regions in the D17Z1 locus), and short tandem repeat (STR) typing using AmpFlSTR Identifiler Plus PCR Amplification Kit was conducted. All extracts from the FFPE tissues were highly degraded, and large differences were observed among total DNA yields determined by these three quantification methods. DNA obtained using QIAamp DNA FFPE Tissue Kit had the highest total DNA yield among all the quantification methods. In STR typing with 1 ng DNA template estimated by quantitative PCR based on 98 bp region in the D17Z1 locus, the greatest number of detected alleles was observed using QIAamp DNA FFPE Tissue Kit. In contrast, EZ1 DNA Investigator Kit and DNA Isolator PS-Rapid Reagent were inferior to the other methods in terms of the DNA yield and the number of detected alleles via STR typing. In conclusion, QIAamp DNA FFPE Tissue Kit was the most effective method for human identification from FFPE tissues among the other DNA extraction methods, considering the results of this study, its cost-effectiveness, and universal use for forensic science.