Patent ID: 7989162

Claim:
A method for determining whether a hepatitis B test virus from a human patient exhibits reduced sensitivity to entecavir relative to a wild-type hepatitis B virus, the method comprising: screening a nucleic acid molecule from the test virus for the presence of entecavir-resistance mutations, wherein the nucleic acid molecule comprises a nucleic acid sequence that encodes a reverse transcriptase domain of a DNA polymerase, and the mutations comprise: (i) mutations at all of codon positions 169, 180, 202 and 204; or (ii) mutations at all of codon positions 169, 180, 184 and 204; wherein codon positions 169, 180, 184, 202 and 204 correspond to positions 95, 106, 110, 128 and 130, respectively, of SEQ ID NO:2; wherein the mutation at codon position 169 is a substitution to threonine, the mutation at codon position 180 is a substitution to methionine, and the mutation at codon position 204 is a substitution to isoleucine or valine, and wherein the presence of mutations comprising combination (i) or (ii) indicates that the test virus exhibits reduced sensitivity to entecavir.