Precore/core mutations of hepatitis B virus genotype D arising in different states of infection

Aim of the study
Precore/core variations and liver disease progression have been suggested. In this study, we aimed to determine the frequency of precore/core mutations in hepatitis B virus (HBV)-infected patients at various clinical stages.

Material and methods
In total, 73 HBV-infected patients including 26 inactive carriers (IC), 20 chronic active (CA), and 27 patients with liver cirrhosis/hepatocellular carcinoma (C/HCC) were randomly selected. The HBV DNA was extracted from the sera and subjected to nested PCR for amplification of precore/core region. The PCR product was then sequenced by the Sanger method.

Results
The stop codon of W28*(G1896A) was determined as the most prevalent mutation (55%) of the precore region. The comparison of groups also demonstrated that core substitutions at residues of S21, E40 and I105 (< 0.05) correlated with the development of the inactive carrier state. Furthermore, the total substitutions in Th epitopes (117-131) were significantly higher in the C/HCC group than the IC and CA groups (p = 0.001).

Conclusions
Our results indicated a high frequency of W28* mutation in HBV studied patients. Moreover, variations including S21, E40 and I105 and R151 that were mapped onto cellular epitopes might be related to inactive state development.