HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Supplementary table Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Google Scholar Articles by Zahn, A. Articles by Allain, J.-P. PubMed PubMed Citation Articles by Zahn, A. Articles by Allain, J.-P. Agricola Articles by Zahn, A. Articles by Allain, J.-P.

Molecular characterization of occult hepatitis B virus in genotype E-infected subjects

Chengyao Li^2,

Jillian Temple^1,

¹ Division of Transfusion Medicine, Department of Haematology, University of Cambridge, Cambridge, UK
² National Health Service Blood and Transplant, Cambridge Blood Centre, Cambridge, UK
³ Department of Obstetrics and Gynaecology, Komfo Anokye Teaching Hospital, Kumasi, Ghana
⁴ Transfusion Medicine Unit, Department of Medicine, Komfo Anokye Teaching Hospital, Kumasi, Ghana

Correspondence
Jean-Pierre Allain
jpa1000{at}cam.ac.uk

Occult hepatitis B virus (HBV) infection (OBI), defined as the presence of HBV DNA without detectable HBV surface antigen (HBsAg), is frequent in west Africa, where genotype E is prevalent. The prevalence of OBI in 804 blood donors and 1368 pregnant women was 1.7 and 1.5 %, respectively. Nine of 32 OBI carriers were evaluated with HBV serology, viral load and complete HBV genome sequence of two to five clones. All samples except one were anti-HBV core antigen-positive and three contained antibodies against HBsAg (anti-HBs). All strains were of genotype E and formed quasispecies with 0.20–1.28 % intra-sample sequence variation. Few uncommon mutations (absent in 23 genotype E reference sequences) were found across the entire genome. Two mutations in the core region encoded truncated or abnormal capsid protein, potentially affecting viral production, but were probably rescued by non-mutated variants, as found in one clone. No evidence of escape mutants was found in anti-HBs-carrying samples, as the ‘a’ region was consistently wild type. OBI carriers constitute approximately 10 % of all HBV DNA-viraemic adult Ghanaians. OBI carriers appear as a disparate group, with a very low viral load in common, but multiple origins reflecting decades of natural evolution in an area essentially devoid of human intervention.

Present address: Institute of Virology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515, PR China.

Present address: Functional Genomics of Drug Resistance, Cancer Research UK Cambridge Research Institute and Department of Oncology, University of Cambridge, Li Ka-Shing Centre, Cambridge, UK.

The GenBank/EMBL/DDBJ accession numbers for the nucleotide sequences analysed in this study are EU239217–EU239226.

A supplementary table showing primers used for sequencing full-length HBV amplicons is available with the online version of this paper.