Full sequence analysis and characterization of a human astrovirus type 1 isolate from South Korea

Human astroviruses are recognized as an important cause of infantile gastroenteritis around the world. In South Korea, sporadic cases of HAstV infection have been reported since 2002. However, hitherto, there have been no studies reporting the whole genome sequence of an HAstV isolate from South Korea. Hence, we sequenced and analyzed the entire genome of an HAstV-1 strain (lhar) that was isolated in Seoul, South Korea. The whole-genome sequence analysis revealed 3 open reading frames comprising the whole genome: ORF1a (2,763 bp), ORF1b (1,548 bp), and ORF2 (2,364 bp). The lhar strain showed amino acid identities with 8 other reference strains of 87.6-98.7%, 94.2-98.8%, and 62.6-99.0% in the ORF1a, ORF1b, and ORF2 regions, respectively. The amino acid sequence of the capsid region encoded by ORF2 was compared with a total of 19 HAstV-1 strains and 8 HAstVs reference strains isolated in various countries. This revealed 1 amino acid substitution, at aa412 (Pro → Arg) in ORF2. This study, the first to report the full-length sequence of an HAstV isolated in South Korea, is meaningful in that it can be used as a full-length HAstV sequence standard for future comparison studies. It may also prove useful to the field of public health field by facilitating the diagnosis and the prediction of new emerging variants.