Manganese citrate improves base-calling accuracy in DNA sequencing reactions using rhodamine-based fluorescent dye-terminators

While dideoxy-terminators labeled with rhodamine-based fluorescent dyes provide the most versatile method of automated DNA sequencing, variation in peak heights reduces base-calling accuracy. We describe a simple approach that uses additions of a manganese salt and the metal buffer sodium citrate (MnCit) to overcome this limitation. This modification reduces peak height variability >2-fold and significantly increases the number of accurately read bases in DNA sequences.