DNA identity testing in stained tissue samples

Determination of donor identity and commonality of origin among paraffin embedded tissues and slides becomes important when criminal or civil action is taking place. Determining the identity of the specimens' donor can be facilitated by forensic DNA identity testing. Previous work has shown that PCR based identity testing is feasible on fixed, paraffin-embedded tissues and slides. The use of differential staining and other contrast enhancing procedures may alter the ability to recover template DNA for PCR based identity testing. Using sections on slides that had been treated with a variety of different stains/immuno-probes (Hematoxylin and Eosin, Gridely's Silver Method for Reticulum, Grocott's Methenamine Silver, immunofluorescent staining, IN-SITU hybridization, etc.) the ability to perform PCR based identity testing was evaluated. Samples were also subjected to a destaining procedure to remove stains that potentially could interfere with the DNA extraction or PCR process. Destaining was found to improve the ability to amplify some stained specimens. Samples were subjected to Chelex(R) extraction for template preparation. The process utilized and its advantages are discussed.