Prevalence and Clinical Significance of Hepatitis B Viral Genotypes and Mutations

Abstract

Hepatitis B virus (HBV) infection is a major public health problem, with more than 400 million HBV carriers estimated worldwide. Chronic HBV infection is associated with a diverse clinical spectrum of liver damage ranging from asymptomatic carrier status, chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). There have been increasing lines of evidence to indicate influences of HBV genotypes and mutations on the outcome of liver disease, particularly the development of HCC. The project is aimed to study the prevalence and clinical significance of genotypes and mutations in Precore/core and X regions of HBV in Thai patients. Our study demonstrate that genotype C and B were the predominant strains, accounting for approximately 75 and 20% of patients, respectively. Patients with HBV genotype C, compared to those with genotype B, had a higher positive rate of HBeAg and exhibited earlier progression of cirrhosis and HCC. However, there was no difference in the risk of developing HCC and its prognosis between patients with genotypes B and C. Furthermore, certain X gene mutations and, particularly, CP mutations in young patients may contribute to the development of HCC As the genetic variability of HBV differs geographically and the data available in Thailand are still limited, our study will provide useful information regarding the epidemiology and clinical relevance of HBV genotypes and mutations in Thai populations.