Detection of hyper-conserved regions in hepatitis B virus X gene potentially useful for gene therapy

Carolina González, David Tabernero, Maria Francesca Cortese, Josep Gregori, Rosario Casillas, Mar Riveiro-Barciela, Cristina Godoy, Sara Sopena, Ariadna Rando, Marçal Yll, Rosa Lopez-Martinez, Josep Quer, Rafael Esteban, Maria Buti, Francisco Rodríguez-Frías

Research output: Contribution to journalArticleResearchpeer-review

11 Citations (Scopus)


© The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved. AIM To detect hyper-conserved regions in the hepatitis B virus (HBV) X gene (HBX) 5’ region that could be candidates for gene therapy. METHODS The study included 27 chronic hepatitis B treatment-naive patients in various clinical stages (from chronic infection to cirrhosis and hepatocellular carcinoma, both HBeAg-negative and HBeAg-positive), and infected with HBV genotypes A-F and H. In a serum sample from each patient with viremia > 3.5 log IU/mL, the HBX 5’ end region [nucleotide (nt) 1255-1611] was PCR-amplified and submitted to next-generation sequencing (NGS). We assessed genotype variants by phylogenetic analysis, and evaluated conservation of this region by calculating the information content of each nucleotide position in a multiple alignment of all unique sequences (haplotypes) obtained by NGS. Conservation at the HBx protein amino acid (aa) level was also analyzed. RESULTS NGS yielded 1333069 sequences from the 27 samples, with a median of 4578 sequences/sample (2487-9279, IQR 2817). In 14/27 patients (51.8%), phylogenetic analysis of viral nucleotide haplotypes showed a complex mixture of genotypic variants. Analysis of the information content in the haplotype multiple alignments detected 2 hyper-conserved nucleotide regions, one in theHBX upstream non-coding region (nt 1255-1286) and the other in the 5’ end coding region (nt 1519-1603). This last region coded for a conserved amino acid region (aa 63-76) that partially overlaps a Kunitz-like domain. CONCLUSION Two hyper-conserved regions detected in theHBX 5’ end may be of value for targeted gene therapy, regardless of the patients’ clinical stage or HBV genotype.
Original languageEnglish
Pages (from-to)2095-2107
JournalWorld Journal of Gastroenterology
Issue number19
Publication statusPublished - 21 May 2018


  • Gene therapy
  • HBV conserved regions
  • Hepatitis B X gene
  • Hepatitis B X protein
  • Hepatitis B virus
  • Next-generation sequencing
  • Small interference RNA


Dive into the research topics of 'Detection of hyper-conserved regions in hepatitis B virus X gene potentially useful for gene therapy'. Together they form a unique fingerprint.

Cite this