Selection for a pre-C stop codon mutation in a hepatitis B virus variant with a pre-C initiation codon mutation during interferon treatment
1991; Elsevier BV; Volume: 13; Issue: 3 Linguagem: Inglês
10.1016/0168-8278(91)90083-n
ISSN1600-0641
AutoresTeresa Santantonio, Maria–Christina Jung, Ralf Schneider, Giuseppe Pastore, Gerd R. Pape, Hans Will,
Tópico(s)Bacteriophages and microbial interactions
ResumoHepatitis B virus (HBV) variants with a stop codon, a mutated translation initiation codon or other mutations in the pre-C region which prevent e-antigen expression are highly prevalent in anti-HBe chronic carriers and can be positively selected from a mixed virus infection. Our laboratories recently described pre-C variants with two pre-C mutations which prevent HBeAg expression. Here we have investigated whether there is a selective pressure for acquisition of the second pre-C mutation. By direct sequencing of amplified HBV DNA from sera of a chronic carrier taken during a 6-year follow-up, we found that genomes of a virus population virtually all had a pre-C translation initiation codon mutation and about 50% had an additional stop codon mutation. With the onset of interferon treatment, the genomes with the stop codon mutation increased to more than 95% while the frequency of the translation initiation codon mutation in all genomes remained constant. These data indicate positive selection (possibly immune-mediated and HBeAg-targeted) for a second pre-C mutation. This putative enhancement of negative translational control may be present because a pre-C translation initiation codon mutation cannot totally prevent HBeAg expression and is therefore less frequent.
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