Human astroviruses (HAstVs) are important enteric pathogens and can be classified genetically and antigenically into eight types. During surveillance of HAstVs in Italy, type-4 HAstVs were detected only sporadically and found to cluster into two distinct genetic groups. Upon sequence analysis of the 3' end of the polymerase gene (ORF1b) and of the full-length ORF2, the 2008 type-4 HAstV strains were characterised as a novel ORF2 genetic lineage, designated as 4c. The 2008 type-4 HAstVs also shared the ORF1b gene with similar HAstV-4c strains detected globally, thus displaying a conserved ORF1b/ORF2 asset. By interrogation of the databases, this novel lineage 4c accounted for 60.8% of the type-4 strains identified worldwide and the vast majority of recent type-4 HAstVs. The 2002 type-4 HAstVs displayed a type-4b ORF2, whereas in the ORF1b they resembled type-1 HAstVs. This inconsistency suggests a possible recombinant origin, with the RNA switch taking place upstream the ORF1b/ORF2 junction region. Also, recombination likely played a role in the diversification of the ORF2 of the three type-4 lineages. Multi-target analysis is required for appropriate characterisation and identification of recombinant HAstVs.
Martella, V., Medici, M.C., Terio, V., Catella, C., Bozzo, G., Tummolo, F., et al. (2013). Lineage diversification and recombination in type-4 human astroviruses. INFECTION GENETICS AND EVOLUTION, 20, 330-335 [10.1016/j.meegid.2013.09.015].
Lineage diversification and recombination in type-4 human astroviruses
GIAMMANCO, Giovanni;DE GRAZIA, Simona
2013-01-01
Abstract
Human astroviruses (HAstVs) are important enteric pathogens and can be classified genetically and antigenically into eight types. During surveillance of HAstVs in Italy, type-4 HAstVs were detected only sporadically and found to cluster into two distinct genetic groups. Upon sequence analysis of the 3' end of the polymerase gene (ORF1b) and of the full-length ORF2, the 2008 type-4 HAstV strains were characterised as a novel ORF2 genetic lineage, designated as 4c. The 2008 type-4 HAstVs also shared the ORF1b gene with similar HAstV-4c strains detected globally, thus displaying a conserved ORF1b/ORF2 asset. By interrogation of the databases, this novel lineage 4c accounted for 60.8% of the type-4 strains identified worldwide and the vast majority of recent type-4 HAstVs. The 2002 type-4 HAstVs displayed a type-4b ORF2, whereas in the ORF1b they resembled type-1 HAstVs. This inconsistency suggests a possible recombinant origin, with the RNA switch taking place upstream the ORF1b/ORF2 junction region. Also, recombination likely played a role in the diversification of the ORF2 of the three type-4 lineages. Multi-target analysis is required for appropriate characterisation and identification of recombinant HAstVs.File | Dimensione | Formato | |
---|---|---|---|
AstroType4IGE13.pdf
Solo gestori archvio
Descrizione: Articolo principale
Tipologia:
Versione Editoriale
Dimensione
1.37 MB
Formato
Adobe PDF
|
1.37 MB | Adobe PDF | Visualizza/Apri Richiedi una copia |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.