Complete genome sequences of three sub-genotype 2.1b isolates of classical swine fever virus in China

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Introduction: Classical swine fever (CSF) has caused severe economic losses in pig production in many countries. Recent CSF outbreaks in China are mainly associated with sub-genotype 2.1 of CSF virus (CSFV). Although there is abundant information regarding 2.1 isolates, few data are available on whole-genome analysis.

Material and Methods: The biological and genome characteristics of three recently emerged Chinese CSFV isolates, i.e. SD2014-1, SD2014-2, and SD2014-3, were fully analysed.

Results: Sequence analysis showed that the isolates shared 83.4%–95.0% nucleotide identity with eight other CSFV isolates. In addition, the 5' untranslated region (5'UTR) and the non-structural (NS) proteins NS3, NS4A, and NS4B were more conserved than other regions of the genome. Phylogenetic analysis based on the complete genome sequences or full-length structural protein E2 gene sequences revealed that the three isolates belonged to sub-genotype 2.1b. In addition, several unique molecular characteristics of the 5'UTR, 3'UTR, and E2 were identified.

Conclusion: The genomic variations of the three isolates will support further analysis of virulence determinants and the evolutionary trend of CSFV.

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Journal of Veterinary Research

formerly Bulletin of the Veterinary Institute in Pulawy

Journal Information

IMPACT FACTOR J Vet Res 2017: 0.811

CiteScore 2017: 0.68

SCImago Journal Rank (SJR) 2017: 0.29
Source Normalized Impact per Paper (SNIP) 2017: 0.484


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