Comparison of two different DNA extraction methodologies for critical bone or teeth samples

Through this study we compared two DNA extraction methods for skeletal or dental human samples. For such task there were analysed 38 samples from 19 individuals, selecting two samples from each one. When it was possible, we selected dental complete samples, without cracks or cavities, and also with a natural light colour. When there were no dental samples available, there were selected preferably skull or diaphysis of long bone. The two samples from each individual were processed individually in two different laboratories (Laboratories 1 and 2). There were employed a different DNA extraction methodology in each laboratory, applying in Laboratory 1 the protocol proposed by Rohland and Hofreiter (2009), and in Laboratory 2 a commercial kit for purification. Finally, in order to compare the efficiency of both methodologies, in Laboratory 2, aDNA quantification by Real Time PCR (RTPCR) was performed, by the amplification of two different size mitochondrial DNA fragments. In this way, it was possible to evaluate the efficiency of each protocol, and to discuss advantages and disadvantages of each one.