title: Truncated fragments in polymerase chain reaction-based DNA sequencing.
abstract: Reconstitution experiments were performed by using an ordinary dye-primer protocol of a template spiked with known amounts of truncated fragments. We observed that as little as 0.2 mole-percentage of the truncated fragment caused sequence interpretation problems. Two protocols were developed for sequencing with dye-labeled terminators; this eliminates the problems with truncated fragments, which are adapted to a one-dye chemistry. One was designed for single extension sequencing using T7 DNA polymerase and one for cycle sequencing. To avoid precipitation and centrifugation and to facilitate automation, the dye-terminator protocols included the use of a biotinylated sequencing primer. Thus, the Sanger fragments were recovered and, by magnetic separation, washed and released by formamide, EDTA, and heat treatment before loading on the electrophoresis gel. Integrated procedures for sequencing PCR products using one-dye-labeled terminators suitable for automation are described. High quality data in terms of long reads and detection of polymorphisms is obtained. The protocols serve as attractive alternatives to internal labeling and dye-primer approaches.
authors.affiliation: Department of Biotechnology, Royal Institute of Technology, Stockholm, Sweden.
authors.forename: J
authors.initials: J
authors.lastname: Westberg
authors.forename: A
authors.initials: A
authors.lastname: Holmberg
authors.forename: M
authors.initials: M
authors.lastname: Uhlén
authors.forename: B
authors.initials: B
authors.lastname: Pettersson
mesh_terms: D001483:Base Sequence; D004247:DNA / Q000032:analysis*; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods*; D017422:Sequence Analysis, DNA / Q000379:methods*; D013698:Templates, Genetic
chemical_list: D005456:Fluorescent Dyes; D004247:DNA; D016650:Fluorescein-5-isothiocyanate