FIGURE 1: Structure and organization of the HBV genome [16]. The four protein-coding regions are shown by semicircular arrows. They include the precore (pre-C) and core gene (C gene); the polymerase gene (P gene); the X gene; and the envelope genes pre-S1, pre-S2, and S (S gene). The positions of the direct repeats (DR1 and DR2) are indicated. Genome positions may change, depending on the HBV genotype [16]. Abbreviations: HBV, hepatitis B virus; P gene, the polymerase gene; C gene, the core gene; S gene, the surface gene.

16. Hsu HY, Chang MH, Hsieh KH, Lee CY, Lin HH, Hwang LH, Chen PJ, Chen DS (1992). Cellular immune response to HBcAg in mother-to-infant transmission of hepatitis B virus. Hepatology 15(5): 770-776. http://dx.doi.org/10.1002/hep.1840150505