The S-Gene Mutations in the Circulating HBV Genotypes/Sub-Genotypes Associated with Hepatitis B Infection in Uganda and their Effects on Cytokines Expression in Liver Disease Progression

Abstract

The causal agent for hepatitis B is called hepatitis B virus (HBV). It is a partially double stranded circular DNA virus of the family Hepadnaviridae. It has been implicated as the leading cause of hepatocellular carcinoma and only second to tobacco among the global human carcinogens. Liver damage as a result of HBV infection is due to host immune response and is modulate by cytokines. The HBV is classified into 10 genotype denoted as A, B, C, D, E, F, G, H, I and J together with several sub-genotypes which have diverse geographical distribution. These genotypes influence liver disease progression and severity as well as response to antiviral therapies. Mutations in the S-gene have been implicated in the paradoxical coexistence of HBsAg and the anti-HBs antibodies which is associated with advanced liver diseases including hepatocellular carcinoma and liver cirrhosis.