Genetic characterization of goose astrovirus strain JSSQ isolated from Jiangsu province

Abstract:

[Background] A severe infectious disease characterized with gout has attacked the goslings in Shandong, Anhui, Jiangsu, and Guangdong provinces in China since 2016. [Objective] To study the genetic characteristics of goose astrovirus (GAstV) causing this disease. [Methods] A strain of GAstV, named JSSQ, was isolated from the liver sample of a gosling suspected to be undergoing gout from a goose farm in Jiangsu province. The virus genes were sequenced for the genetic characterization. [Results] GAstV JSSQ strain stably propagated in LMH cells without obvious cytopathic changes. The strain had a full-length genome of 7 175 nt and shared the similarity of 57.3%–99.1% with other reported reference strains of GAstV. The phylogenetic analysis showed that JSSQ was close related to the reference strain AHAU3 and they were in the same branch. Two recombination events occurred at the sites 807 and 2 818 in GAstV JSSQ genome, originating from GD AHAU2 (major parent) and AHAU4 (minor parent). The antigenic epitope analysis showed that there were several amino acid mutations, such as P64S, A224T, A228S, and Q229P, in ORF2 region, which resulted in changes in antigenic epitope. [Conclusion] The biological characteristics may vary between the GAstVs in different areas, and thus attention should be paid to the prevention and control of such viruses.

Key words:goose gout;goose astrovirus;isolation and identification;genetic characterization