“…In this context, for the genotypic evaluation of antiviral resistant hepatitis B virus subpopulations, various monitoring methods have been developed as alternatives to commonly used direct DNA sequencing method. These include, PCR-RFLP method [1,7], PCR-RFMP (restriction fragment mass polymorphism) method [4], methods using conventional PCR with allele specific primers [10,19,20], peptide nucleic acid (PNA) mediated PCR clamping method [8], methods based on real-time PCR [3,5,12,13,17,18] and methods based on immobilized oligonucleotide probes [6,9,11,15,21,22]. The sensitivity of these methods in detecting antiviral resistant HBV subpopulations has been reported to be 5 % in PCR-RFLP method [1], 1 % in PCR-RFMP method [4], 0.5 % in allele specific PCR method [10], 0.01 % in PNA mediated PCR clamping method [8], depending on the experimental settings 10-0.01 % in real-time PCR methods [3,5,12,13,17,18] and 30-5 % in methods using immobilized oligonucleotide probes [6,9,11,21,22].…”