PCR Inhibitory Effects of Aldehyde Fixing Agents on DNA Extracted from Embalmed Human Skeletal Fragments and Teeth Specimens

Abstract

The presence of inhibitors in samples has been the focus of much of the published literature. The difficulties posed by PCR inhibitor-bearing DNA samples have traditionally been addressed by decreasing the inhibitor concentration, either through sample dilution or by further purifying the target DNA. A review composed via Medline Internet search, literature search and contributions from our experiences as well as experiences from colleagues. The recovery of intact high-molecular-weight DNA from formaldehyde-fixed tissues is very poor and that this fragmented DNA amplifies poorly in PCR reactions. For the fact that aldehyde fixed samples of bone or tooth may contain many different inhibitory substances leading to failure of amplification, a multi-faceted approach is the best solution for amplification failure.