All oligonucleotides were synthesized by the Integrated DNA Technologies Inc. (Coralville, IA).
The PCR products were identified by gel electrophoresis and a UV transilluminator after purification.
After PCR amplification, the PCR product was purified by PCR purification kits (QIAquick;
QIAgen, Valencia, CA) and diluted serially with distilled water.
PCR product concentration and quality were measured with a Bio-Rad SmartSpec 3000 spectrophotometer.
The serially diluted PCR products of tDNA were used as DNA samples for the experiments.