bootstrap sampling

The conditions of polymerase chain reaction (PCR) are as follows:

1 cycle (94 degrees for 5 minutes)

35 cycles (94 degrees 30 seconds, 60 degrees 30 seconds, 72 degrees 30 seconds)

1 cycle (72 degrees for 5 minutes)

The PCR amplification products were cloned into Pgem-T vector (Promega Company), and the sequence was analyzed by automatic DNA sequence analyzer (American Applied Biological Systems Company) of Korea Immunoregulation Research Center. According to the reaction steps and sequence analysis results of dye chain terminator, reverse transcription primers and overlapping primers were designed. The position of each nucleic acid in the major capsid protein (MCP) gene is determined at least twice on each DNA strand. The DNA and deduced amino acid sequence were compared with GenBank/EMBL database by BLAST software. Use "CLUSTAL W" software for sequence analysis [23], and then use "Treeview" [20] software to build a phylogenetic tree. The interspecific relationship was determined by adjacency method [22], and the reliability of "NJ tree" was deduced by repeating 1000 times "Felsentein" self-help method [6].