FIG. 1.

Sensitivity of the HBV full-length genome PCR with different thermostable polymerases. (A) Defined amounts of cloned HBV DNA (plasmid pSM2) were amplified for 40 cycles. The 3.2-kb PCR products were resolved in an agarose gel and stained with ethidium bromide. (B) HBV DNA from virus particles in the supernatant of HBV DNA-transfected hepatoma cells was amplified (10⁵ to 10⁶ template molecules). After 20, 25, 30, and 35 cycles an aliquot was removed from the PCR mixture, separated in an agarose gel, and stained with ethidium bromide. All assays produced a signal with 1 ng of HBV DNA as a positive control.