NUCLEOTIDE-SEQUENCE ANALYSIS OF RECENT EPIDEMIC STRAINS OF ENTEROVIRUS-70

Nucleotide sequences of the genome of enterovirus 70 (EV70) isolated i n Osaka in 1993 were determined, and compared with those of the past e pidemic strains. Nucleotide substitution rates in 332 bp, 174 bp, and 178 bp of the genes encoding viral protein (VP)1, VP2, or VP3 were 9.0 , 7.5, and 5.6% between Kumoi-2/93 and J670/71, respectively. Likewise , the putative amino acid substitution rates were 1.8, 0, and 0%. It s eems that the epidemic strains of EV70 in Japan have been evolving at a constant high nucleotide substitution rate but almost all the substi tutions were synonymous.