Purification of PCR Products from Agarose Gels for Direct Sequencing

The advent of direct sequencing of polymerase chain reaction (PCR) products has permitted extremely rapid analysis of DNA mutants and cDNA clones. However, direct PCR sequencing has been problematic for a number of technical reasons, including the presence of impurities and excess oligonucleotide primers used for the PCR amplifications (1 –4 ). Therefore, a number of protocols have been devised that address these technical issues, and allow efficient sequencing of either conventional double-stranded PCR products or asymmetrically amplified single-stranded products (e.g., 1 –4 ). Many of these protocols are described in detail in this volume.