Evaluation of an alkaline lysis method for the extraction of DNA from whole blood and forensic stains for STR analysis

A modified alkaline lysis protocol for extracting DNA from forensically rel evant specimens is evaluated and compared with the chelex 100 method. For w hole blood, bloodstains and sperm stains, both methods yielded comparable r esults after amplification for a pentameric STR locus (HumCD4). The main ad vantages of the new method are: only approximately ten minutes and two pipe tting steps are necessary and the expenses for the extraction are extremely low as only NaOH, TrisHCl buffet and a single microcentrifuge tube are req uired. Alkaline lysis also proved to yield DNA suitable for typing longer S TRs by using dye-labeled primers and capillary electrophoresis. These advan tages should render this protocol especially interesting for high-throughpu t laboratories in combination with multiplex PCR and fluorescent dye techno logy, although the storability of the extracts proved to be problematic.