Hepatitis B virus (HBV) is an enveloped, coated, non-cytopathic and hepatotropic partially double-stranded DNA virus in the family Hepadnaviridae genus Orthohepadnavirus. Despite significant progress in the availability of safe vaccines and antiviral therapies against HBV, it still affects approximately 257 million people worldwide and is responsible for about 887,000 deaths per year around the world [4]. HBV infection, which are associated with acute and chronic liver failure responses to viruses attacked the liver, can result in inactive carrier state, chronic hepatitis, or fulminant hepatitis and put them at high risk to develop advanced liver fibrosis and cirrhosis, and even hepatocellular cancer. Many viral factors, which could affect the disparity of clinical outcomes or disease prognosis during chronic HBV infection, have been reported in previous studies; among them, the viral genotype, as well as HBV mutations ascribing the virus to a certain phenotype, was reported to be the most important factor influencing viral pathogenesis, including the change of host immune recognition, the enhanced virulence with increased HBV replication and the facilitation of cell attachment or penetration.