An efficient method for the assessment of DNA quality of archival microdissected specimens

Abstract

There will be an increasing need of methods for assessing the suitability of specimens for genetic-based assays as DNA markers become an integral part of molecular diagnosis. The targeting of specimens for specific analyses will require the ability to rapidly screen for DNA quality. Conventional methods such as Southern analysis and gene specific-polymerase chain reaction (PCR) often require quantities of material that represent a significant portion of the specimen, especially in microdissected samples. Here we describe a novel application of a commonly used PCR-based DNA-fingerprinting technology that requires minimal quantities of DNA to simultaneously assess multiple regions throughout the genome for DNA quality. Randomly amplified polymorphic DNA (RAPD) PCR generates DNA fragments of a broad size range with the product size reflecting the degree of sample fragmentation. Fourteen DNA samples extracted from cells microdissected from seven formalin-fixed, paraffin-embedded oral cancer biopsies were assessed for DNA quality using gene-specific PCR and RAPD-PCR. Although the more conventional assay required 2-ng DNA (or 300-cell equivalents) to examine DNA quality at a single locus, RAPD-PCR provided a more informative profile of DNA quality from the same microdissected archival specimens.