Application of extraction and analysis of nuclear DNA from cortical bone in forensic medicine.

Objective:To investigate the nuclear DNA extraction from cortical bones of which are less impacted by the environmental effect and biological effect of the dead and the analysis of the DNA typing will be successfully done to do individual identification or parentage testing. Methods: Genomic DNA was extracted from the cortical bone of shinbone of ten bones using the proteinase K/SDS-based organic method, the Chelex-100 method, a combined method, and the organic method combined with magnetic beads purification method. Target DNA was simultaneously amplified using a fluorescent multiplex ABI Identifier kit. The PCR products were analyzed on the ABI 3130 Genetic Analyzer. Results: The result showed that the STR genotype profiles obtained through the organic method were acceptable, despite preferential amplification at some loci. In contrast, no readable profiles could be determined when DNA was extracted by the Chelex-100 method, and there are a large number of allles missing. Our data suggest that cortical bone of shinbone can be used for nuclear DNA analysis, but the type of DNA isolation method used is critical. The traditional organic extraction method works reasonably well for cortical bone of shinbone DNA isolation, and combination of organic extraction and the Chelex-100 method or combination of organic extraction and magnetic beads purification works best. Conclusions: The feasibility of extraction and analysis of nuclear DNA from cortical bones of the dead and the STR genotype profiles were acceptable.