The GB hepatitis viruses.

The genomes of three new flavi-like viruses, GBV-A, GBV-B and GBV-C have been identified. Nucleic acid molecules corresponding to the genomes of GBV-A and GBV-B were isolated from tamarins with hepatitis which had been infected with the GB agent. RNA sequences corresponding to GBV-C have been shown to be present in sera from humans with non-A-E hepatitis. Sequence comparisons show that these three viruses are more closely related to each other and to hepatitis C virus (HCV) than to any other known viruses. Together with HCV they appear to form a discrete cluster of related viruses within the larger genus of flaviviridae. The pathological significance of these viruses and their association with hepatitis is currently emerging.