The simplicity of the nexttec single-step preparation method produced reliable reproducible results with very high sensitivity. This method has impressive advantages compared with silica-based protocols. Data evaluated with nexttec clean columns were identical to the control samples previously genotyped using the silica-based DNA extraction method. In all of the samples, however, the nexttec clean column method with a fill height of 7 mm produced a higher yield of amplification products than the silica method, probably because of the higher DNA amount in the amplification setup. All samples analyzed with DNA isolated by the nexttec clean column method with a fill height of 14 mm resulted in a higher yield of amplification products than the nexttec method with a fill height of 7 mm. DNA was extracted from nine stamps using a Qiagen QIAamp DNA Mini Kit (silica method) and a Genomic DNA Isolation Kit for tissue and Cells supplied by nexttec. Each stamp was licked once by the same person. The DNA extraction is described in detail for each method. 2 tables, 3 figures, and 7 references