Objective: To investigate the prevalence of three lamivudine-resistant HBV mutants in lamivudine-treated Chinese patients.
Methods: Using three pairs of of HBV polymerase gene B and C domain fragments were amplified by PCR. The PCR products were then digested by restriction enzyme Nde I and Nla III. The digested products were analyzed by electrophoresis. With this method, the prevalence of the three lamivudine-resistant mutants in lamivudine-treated Chinese patients was investigated.
Results: After Nde I digestion of p24 and p29 amplified product, HBV wild type could be easily separated from YMDD mutant. At the same time, YIDD could be separated from YVDD mutant after Nla III digestion of p24 and p29 amplified product. By this method, the authors found that these eleven patients were infected with lamivudine-resistant mutants. Six of them were infected with M5501 mutant; five were infected with M550V mutant (one of them had both M550V and L526M mutations).
Conclusion: The method of the present study was demonstrated to be an easy way to detect HBV lamivudine-resistant mutants and can be applied to clinical monitoring of lamivudine resistance.