Test Details: There are various HBV mutations in the HBV genome, Mutations in the basal core promoter are also associated with increased HBV replication and an increased incidence of advanced liver diseases such as cirrhosis and HCC. A precore mutant is a variety of hepatitis B virus that does not produce hepatitis B virus e antigen (HBeAg). These mutants are important because infections caused by these viruses are difficult to treat and can cause infections of prolonged duration and with a higher risk of liver cirrhosis.