The PCR assays used 1 μl of template DNA in a 25 μl reaction mixture containing 2 mM of Tris-HCl (pH 8.0), 10 mM of KCl, 10 uM of EDTA, 100 uM of DTT, 0.05% Tween 20, 0.05% Nonidet P-40, 5% glycerol, 2.5 mM of dNTP, 5 units of Ex Taq DNA (TaKaRa Bio Inc., Shiga, Japan), and 10 pM of each primer. The reactions were performed in a T Gradient Thermal Cycler (Biometra, Göttingen, Germany) programmed for one cycle of 10 min at 95°C, followed by 35 cycles of 30 s at 95°C, 30 s at 60°C, and 30 s at 72°C, with a final extension step for 7 min at 72°C. The amplicons were analyzed by electrophoresis in a 2% agarose gel in TAE buffer.
The TaqMan PCR assay was carried out using 2 μl of DNA template, 8.5 μl of Premix Ex Taq (TaKaRa Bio Inc., Shiga, Japan), 1 μl of TaqMan probe (10 pmoles/μl), 0.5 μl (10 pmoles/μl) of each nested primer, and 12.5 μl of DEPC-DW (Bioneer, Daejeon, Korea). Real-time PCR amplifications were performed in a Smart CyclerTM System (Cepheid, Sunnyvale, CA, USA) with 40 cycles at 95°C for 30 sec and 60°C for 20 sec after initial incubation for 30 sec at 95°C.