Highly efficient automated extraction of DNA from old and contemporary skeletal remains.

We optimised the automated extraction of DNA from old and contemporary skeletal remains using the AutoMate Express system and the PrepFiler BTA kit. 24 Contemporary and 25 old skeletal remains from WWII were analysed. For each skeleton, extraction using only 0.05 g of powder was performed according to the manufacturer's recommendations (no demineralisation - ND method). Since only 32% of full profiles were obtained from aged and 58% from contemporary casework skeletons, the extraction protocol was modified to acquire higher quality DNA and genomic DNA was obtained after full demineralisation (FD method). The nuclear DNA of the samples was quantified using the Investigator Quantiplex kit and STR typing was performed using the NGM kit to evaluate the performance of tested extraction methods. In the aged DNA samples, 64% of full profiles were obtained using the FD method. For the contemporary skeletal remains the performance of the ND method was closer to the FD method compared to the old skeletons, giving 58% of full profiles with the ND method and 71% of full profiles using the FD method. The extraction of DNA from only 0.05 g of bone or tooth powder using the AutoMate Express has proven highly successful in the recovery of DNA from old and contemporary skeletons, especially with the modified FD method. We believe that the results obtained will contribute to the possibilities of using automated devices for extracting DNA from skeletal remains, which would shorten the procedures for obtaining high-quality DNA from skeletons in forensic laboratories.