Jc. Erker et al., MOLECULAR-CLONING AND CHARACTERIZATION OF A GB VIRUS-C ISOLATE FROM APATIENT WITH NON-A-E HEPATITIS, Journal of General Virology, 77, 1996, pp. 2713-2720
Recently, the isolation of a novel virus, GB virus C (GBV-C), associat
ed with cryptogenic hepatitis has been reported. Following the molecul
ar cloning of this virus genome, it became apparent that the genomic s
equence did not encode a protein resembling a nucleocapsid or core-lik
e protein similar to those observed in other flaviviruses, pestiviruse
s, hepatitis C virus (HCV) and GB virus B. Similar findings were subse
quently observed in the cloning of two viral genomes representing isol
ates of GBV-C, namely hepatitis G virus (HGV). To verify the presence
or absence of a viral nucleocapsid protein, identify conserved protein
motifs and determine the overall genomic variability, an additional v
irus isolate has been characterized. Here we report the full-length ge
nomic sequence of GBV-C(EA), isolated from an East African suffering f
rom acute non-A-E hepatitis, GBV-C(EA) was compared with the prototype
West African isolate (GBV-C) and the two HGV isolates from the United
States. The analyses demonstrate several characteristics of these nov
el viruses. (1) The degree of variability within the 5' nontranslated
region (NTR) approximates that observed between HCV isolates. (2) The
nucleotide sequence of the coding region and the 3' NTR is highly cons
erved between these isolates, in contrast to the extensive variability
observed between HCV isolates from distinct geographical locations. (
3) There is a high degree of amino acid conservation across the precur
sor polyproteins of these isolates; most striking is the lack of 'hype
rvariable' regions within the envelope proteins. (4) There appears to
be no nucleocapsid protein near the amino terminus of the GBV-C/HGV po
lyproteins.