Objectives: To investigate the prevalence of the core promoter variant in Chinese HBV carriers and to explore the clinical and epidemiological problems of the variant.
Methods: A novel method for detecting the double mutation in core promoter was developed. By using an antisense primer that starts at nt 1765 and bears a mismatch at nt 1767, we introduced an artificially created Bcl I cleavage site if the double mutation was present. The prevalence and clinical significance of mutation in the core promoter were investigated in 114 Chinese individuals infected with HBV.
Results: Serum samples from 37 asymptomatic carriers and patients harbored core promoter mutant, some with precore mutation. The prevalence was higher in carriers and patients without HBeAg than those with HBeAg. The results in the PCR-RFLP assay perfectly agreed with the data from direct sequencing.
Conclusion: The presumed core promoter mutations resulting in decreased HBeAg synthesis might be one of the factors leading to persistence of HBV infection and active liver disease.