PCR-RFLP based protocol for the detection of hepatitis B virus variants in some lamivudine-untreated chronic hepatitis B virus carriers in Pakistan

ABSTRACT

Hepatitis B virus [HBV] affects more than 350 million people worldwide and is a leading cause of morbidity and mortality in developing countries like Pakistan. Lamivudine has potential to inhibit hepatitis B virus [HBV] replication but long term lamivudine treatment results in mutations in YMDD region of HBV, making this therapy ineffective. In this study, we have optimized a polymerase chain reaction-restriction fragment length polymorphism [PCR-RFLP] based protocol to detect two mutations in HBV DNA polymerase gene [at codon 528 and 552] in chronic hepatitis patients, without any prior lamivudine treatment. HBV genome was extracted and tested by PCR-RFLP for detection of mutations in polymerase gene. Variations in HBV genome were not detected in enrolled patients confirming that lamivudine can be used to treat chronic Hepatitis B in these patients. Several studies have reported the natural occurrence of mutation in YMDD motif of polymerase gene in chronic hepatitis B patients, not treated with lamivudine, but these mutants were not detected in Pakistani lamivudine-untreated chronic hepatitis B patients