Replication of HBV DNA occurs by reverse transcription of an RNA intermediate within cytoplasmic nucleocapsids [22] The same mechanism [97] Genetic diversity 8 major genotypes [105] 1 major genotype (minor sequence differences) [91] Integration into host chromosome Yes [22] Yes, often close to N-myc oncogene region [106] Clinical course of infection were characterized ( Figure 1) . In contrast to self-limiting infection, WHV chronic carriers demonstrate weak or no virus-specific T cell responses against the identified epitopes [72, 73, 99] . The establishment of the assays for monitoring of cellular immune response in woodchucks is of great importance for a reliable evaluation of therapeutic and immunomodulatory strategies for treatment of chronic hepatitis B in the woodchuck model [96, 102, 103 ].