Each 50 lL PCR mixture contained 1.5 mmol/L MgCl2,
0.2 mmol/L of each dNTP, 0.3 lmol/L of each primer, 1 lL of genome
DNA template, and 1.25 units of DNA polymerase. Amplification
was performed on a PTC-225 thermocycler PCR system (MJ
research) according to the following protocol: denatured at 94 C
for 15 min and followed by 35 cycles (94 C for 40 s; 55 C for
40 s; 72 C for 1 min). After the cycle reaction, the product was
incubated at 72 C for 10 min and held at 4 C before use.