Objective: To study the EV71 Chinese strain SHZH98 and analyze its genetic evolution using 3c gene as index.
Methods: The 3C gene cDNA of EV71 Chinese strain SHZH98 was amplified by PCR, the PCR product was sequenced.
Results: The EV71 Chinese mainland strain SHZH98 3C segment was 549 bps in length. Comparison of nucleotide sequences from other enteroviruses which have been published, revealed a higher homology to strain MS, 78.7% at nucleotide level and 93.45% at deduced amino acid level. The homology to strain BrCr was 76.7% at nucleotide level and 89.1% at deduced amino acid level. Taiwan strains POLY,NCKU,TW2086,TW2272 shared a lower homology with Chinese mainland strain SHZH98, 74.0%, 73.8%, 71.9%, 69.8% at nucleotide level and 90.7%, 90.2%, 84.2%, 82.5% at deduced amino acid level. The genetic progress analysis revealed that EV71 Chinese mainland strain SHZH98 3C segment shares more homology with European and American strains than Taiwan strains.
Conclusion: The non-structural protein of EV71 Chinese strains may have different evolutionary process from Taiwan strains.