7 Determining Dye-Induced DNA Mobility Shifts for DNA Sequencing Fragments by Capillary Electrophoresis

Over the past decade, fluorescent end-labeling of DNA fragments has evolved into the preferred method of DNA detection for a wide variety of applications, including DNA sequencing and polymerase chain reaction (PCR) fragment analysis. One of the advantages inherent in fluorescent detection methods is the ability to perform multicolor analyses. Unfortunately, labeling DNA fragments with different fluorescent tags may impart disparate relative electrophoretic mobilities to the labeled fragments. In these instances, mobility-shift corrections must be applied to the electrophoretic data. These corrections may lead to increased error in the estimation of DNA fragment sizes and reduced confidence in DNA sequence information.