Restriction enzyme analysis of the capsid protein gene of different strains of European brown hare syndrome virus

Eight Polish strains of European brown hare syndrome virus, isolated in 1992-93, 1998 and 2001, as well as 2 standard strains: French (F/st) and Italian (It/st) were analysed. The fragments of genome, including the capsid protein gene, were amplified by RT-PCR or N-PCR and digested by endonucleases: Xho I, Sst I, BamH I, Sma I, Hpa II and BsuR I. The results of restriction enzyme digestion were compared with restriction maps, obtained after computer analysis of nucleotide sequences of other European strains, available in GenBank. The results of analysis of Polish strains, isolated in different years, revealed the changes in restriction profiles between them and other European strains. The 3 out of 5 Polish strains detected in 1992-93 demonstrated the same restriction profiles, similar to French "GD" strain. The two other strains revealed, for same endonucleases, restriction patterns similar to ltalian "BS89" or German strains. The strains isolated in 1998 and 2001 demonstrated higher differences in restriction profiles in comparison with Polish and other European strains previously detected. These changes in nucleotide scquences of the part of genome studied, indicate the diversity of EBHSV.