under the following conditions: 95 °C for 5 min, followed by 40 cycles at 95 °C for 30 s, 55 °C for 20 s, 72 °C for 40 s. The nested PCR reaction was carried out using 2 μl of the original first round PCR product as template. Melting curve analysis was performed at 70 °C for 5 s followed by increasing steps (1 °C).