Detection and sequences analysis of sheep hepatitis E virus RNA in Xinjiang Autonomous Region

Abstract:

Abstract：[Obiective] To understand whether hepatitis E virus (HEV) was infectious in sheep in Xinjiang . [Methods] We used reverse transcription-nested polymerase chain reaction(RT-nPCR) to detect HEVRNA in feces. The feces were collected from sheep with positive anti-HEV antibodies in a sheep farm in Xinjiang Autonomous Region. [Results] Six of 54 (11.11%) sheep were positive for HEV RNA. PCR amplification products were cloned, sequenced and analyzed. The homology among HEV of the 6 sheep HEV ORF2 189bp nucleotide amplification sequences was 99.38%-100%. They should belong to the same genotype. They were respectively compared with HEV genotypeⅠ, Ⅱ, Ⅲ and Ⅳ corresponding 189bp nucleotide sequences. The average homology was 78.67%-85.33%, 81.33%-82.67%, 78.67%-84.00% and 84.67%-95.36%. The maximum homology between 6 nucleotide amplification sequences and one sequence of genotype Ⅳ was 94.04%-95.36%. Based on sequence of the nucleic acid fragments, a phylogenetic tree was constructed. Six sheep HEV ORF2 189bp nucleotide amplification sequences in this study and bovine HEV, swine HEV and human HEV locate the same evolutionary vine and belong to genotype Ⅳ. [Conclusion] The finding suggested that infection of HEV probably exists in the sheep group in Xinjiang Autonomous Region and the sheep may be a new animal host except swine in origins of HEV infection.