Sequential Accumulation of the Basal Core Promoter and the Precore Mutations in the Progression of Hepatitis B Virus-Related Chronic Liver Disease

Abstract

Objectives: Despite the pathogenic role of the basal core promoter (BCP) and the precore mutations in chronic hepatitis B virus (HBV) infection, their role in the progression of liver disease is still controversial. We analyzed whether the accumulation of these mutations might enhance the progression of HBV-related chronic liver disease. Methods: Forty consecutive patients at each clinical status were analyzed. Clinical statuses were as follows: HBeAg-positive asymptomatic carrier (HBeAg⁺ ASC) (defined as HBeAg⁺, anti-HBe^–, HBV-DNA⁺ by hybridization, normal ALT); inactive HBsAg carrier; chronic hepatitis B; liver cirrhosis. The genotype and the BCP/precore regions were determined by PCR using genotype specific primers and direct sequencing, respectively. Results: All patients except one were infected with genotype C. The A to T mutation at nucleotide 1762 and/or G to A mutation at nucleotide 1764 were found in 30% in HBeAg⁺ ASC, 65.7% in inactive HBsAg carrier, 95% in chronic hepatitis B, and 90% in liver cirrhosis (p < 0.001). The prevalence of the G to A mutation at nucleotide 1896 was 5% in HBeAg⁺ ASC, 22.5% in inactive HBsAg carrier, 32.5% in chronic hepatitis B, and 50% in liver cirrhosis, respectively (p < 0.001). The T to C/A mutation at nucleotide 1753 in the BCP and G to A mutation at nucleotide 1899 in the precore were more frequent in liver cirrhosis than in the other clinical statuses (p < 0.05). Conclusion: Sequential accumulation of mutations in the BCP/precore has an important role in the progression of HBV-related liver disease.