Published online Apr 28, 2015. doi: 10.3748/wjg.v21.i16.5039
Peer-review started: September 25, 2014
First decision: October 14, 2014
Revised: October 30, 2014
Accepted: January 16, 2015
Article in press: January 16, 2015
Published online: April 28, 2015
AIM: To investigate the clinical implications of hepatitis B virus (HBV) preS1 deletion.
METHODS: We developed a fluorescence resonance energy transfer-based real-time polymerase chain reaction (RT-PCR) that can detect four genotypes (wild type, 15-bp, 18-bp and 21-bp deletion). The PCR method was used in two cohorts of Korean chronic HBV subjects with genotype C infections. Cohort I included 292 chronic HBV subjects randomly selected from Cheju National University Hospital (Jeju, South Korea) or Seoul National University Hospital (Seoul, South Korea), and cohort II included 90 consecutive chronic HBV carriers recruited from Konkuk University Hospital (Seoul, South Korea); the cohort II patients did not have hepatocellular carcinoma or liver cirrhosis.
RESULTS: The method proposed in this study identified 341 of 382 samples (89.3%). Deletion variants were identified in 100 (29.3%) of the 341 detected samples. In both cohorts, the subjects with deletions had a significantly higher Hepatitis B virus e antigen (HBeAg)-positive seroprevalence [cohort I, wild (51.0%) vs deletion (75.0%), P < 0.001; cohort II, wild (69.2%) vs deletion (92.9%), P = 0.002] and higher HBV DNA levels [cohort I, wild (797.7 pg/mL) vs deletion (1678.9 pg/mL), P = 0.013; cohort II, wild (8.3 × 108 copies/mL) vs deletion (2.2 × 109 copies/mL), P = 0.049], compared to subjects with wild type HBV.
CONCLUSION: HBV genotype C preS1 deletion may affect disease progression in chronic HBV subjects through an extended duration of HBeAg seropositive status and increased HBV replications.
Core tip: Our data indicate that the hepatitis B virus (HBV) genotype C preS1 deletion might significantly contribute to disease progression in chronic HBV subjects through an extended duration of Hepatitis B virus e antigen seropositive status and increased HBV replication. This study provides novel insight into the greater infectivity and virulence of genotype C compared with other genotypes. In addition, the fluorescence resonance energy transfer-based real-time polymerase chain reaction used to detect the preS1 deletion shows promise for the earlier prediction of the risk of liver disease progression in chronic HBV subjects.