Genogroup I (GI) Noroviruses are highly contagious, non-enveloped RNA viruses that cause acute gastroenteritis in humans. The ORF1 (Open Reading Frame 1) encodes a large polyprotein that is cleaved into nonstructural proteins, including the RNA-dependent RNA polymerase (RdRp) essential for viral replication. The RdRp region within ORF1 is highly conserved in GI strains, making it a key target for RT-qPCR assays in clinical diagnostics and environmental monitoring, particularly in water and food safety testing.
Genogroup II (GII) Noroviruses are the most prevalent cause of viral gastroenteritis worldwide, often responsible for large outbreaks in healthcare and community settings. The ORF1 region encodes nonstructural proteins, including the RNA-dependent RNA polymerase (RdRp), which is essential for viral replication. The RdRp domain within ORF1 is highly conserved across GII strains, making it a critical molecular target for RT-qPCR assays used in clinical diagnostics and environmental surveillance, especially in water and wastewater monitoring.
